Composition of Titan’s Dunes: Constraints from Cassini VIMS and RADAR Principal Investigator: Dr. Paul O. Hayne (Jet Propulsion Laboratory) Co-Investigators: Dr. Alexander G. Hayes (Cornell University), Dr. Thomas B. McCord (Bear Fight Institute), Dr. Jean-Philippe Combe (Bear Fight Institute) Collaborators: Dr. Jason W. Barnes (University of Idaho), Dr. Oded Aharonson (Weizmann Institute), Dr. Antoine Lucas (University of Paris), and Dr. Christophe Sotin (Jet Propulsion Laboratory) Proposal submitted in response to NASA solicitation NNH13ZDA001N-CDAPS: Cassini Data Analysis and Participating Scientists May 3, 2013 Table of Contents SCIENCE-TECHNICAL-MANAGEMENT ......................................................................................1 1 SCIENTIFIC RATIONALE AND OBJECTIVES........................................................................................... 1 1.1 Motivation and Proposed Research ................................................................................. 1 1.2 Background ...................................................................................................................... 2 2 TECHNICAL APPROACH AND METHODOLOGY .................................................................................... 3 2.1 Data Acquisition and Reduction ....................................................................................... 3 2.2 Atmospheric Correction to VIMS Data ............................................................................. 5 2.3 Dune Mask from De-noised RADAR Data ........................................................................ 7 2.4 Isolation of Dune Reflectance Spectra ............................................................................. 8 2.5 Composition ................................................................................................................... 10 3 PERCEIVED IMPACT..................................................................................................................... 11 4 RELEVANCE ............................................................................................................................... 11 5 WORK PLAN .............................................................................................................................. 12 5.1 Key milestones for accomplishments ............................................................................ 12 5.2 Management structure and role of personnel .............................................................. 13 APPENDIX: PARTICIPATING SCIENTIST REQUEST ................................................................... 15 A.1 OBJECTIVES AND EXPECTED CONTRIBUTIONS .............................................................................. 15 A.1.1 Science background and objectives ........................................................................... 15 A.1.2 Capabilities and Qualifications .................................................................................. 17 A.2 RELEVANCE TO CASSINI SCIENCE GOALS ..................................................................................... 18 A.3 COLLABORATIONS WITH THE CASSINI SCIENCE TEAM .................................................................... 19 A.4 COMPLIANCE WITH CASSINI RULES ............................................................................................ 19 REFERENCES ........................................................................................................................ 20 Composition of Titan’s Dunes BIOGRAPHICAL SKETCHES .................................................................................................... 25 PAUL OTTINGER HAYNE .................................................................................................................. 25 ALEXANDER GERARD HAYES ............................................................................................................ 28 JEAN-PHILIPPE COMBE ................................................................................................................... 29 THOMAS B. MCCORD .................................................................................................................... 30 CURRENT AND PENDING SUPPORT ....................................................................................... 31 PRINCIPAL INVESTIGATOR: PAUL O. HAYNE ........................................................................................ 31 CO-INVESTIGATOR: ALEXANDER G. HAYES ......................................................................................... 32 CO-INVESTIGATOR: JEAN-PHILIPPE COMBE ........................................................................................ 34 CO-INVESTIGATOR: THOMAS MCCORD ............................................................................................. 35 BUDGET JUSTIFICATION ....................................................................................................... 36 BUDGET JUSTIFICATION: NARRATIVE ................................................................................................. 36 Summary of Personnel and Work Efforts.............................................................................. 36 Facilities and Equipment ....................................................................................................... 36 Rationale and Basis of Estimate ........................................................................................... 36 BUDGET JUSTIFICATION: DETAILS ..................................................................................................... 37 Year 1: ................................................................................................................................... 37 Year 2: ................................................................................................................................... 37 BUDGET DETAILS.................................................................................................................. 39 BUDGET JUSTIFICATION: PARTICIPATING SCIENTIST REQUEST ............................................... 40 NARRATIVE ................................................................................................................................... 40 Summary of Personnel and Work Efforts .............................................................................. 40 Facilities and Equipment ....................................................................................................... 40 Rationale and Basis of Estimate ........................................................................................... 40 DETAILS ....................................................................................................................................... 40 Year 1 .................................................................................................................................... 40 Year 2 .................................................................................................................................... 40 BUDGET DETAILS: PARTICIPATING SCIENTIST REQUEST ......................................................... 41 2 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Science-Technical-Management 1 Scientific Rationale and Objectives 1.1 Motivation and Proposed Research Titan’s equatorial dune fields constitute a major geologic terrain, extending from approximately -30 to 30 °N latitude and encompassing nearly all longitudes. While these features have been studied extensively with a variety of Cassini datasets (e.g. Lorenz and Radebaugh 2007; Le Gall et al., 2012), their composition remains uncertain (Barnes et al., 2008). Cassini RADAR data indicate optical behavior consistent with porous solid hydrocarbons, or even extremely porous water ice deposits (Janssen et al., 2009). Reflectance data from the Cassini Visual and Infrared Mapping Spectrometer (VIMS) that are not corrected for atmospheric effects are highly ambiguous, due to the strong absorption and scattering within Titan’s hazy, methane-rich atmosphere. Preliminary analysis of the VIMS data indicates that the dunes are somewhat less water ice-rich than surrounding terrain, possibly indicating a hydrocarbon composition (Barnes et al., 2008). However, this and other existing studies were limited to relative spectroscopy, due to variable atmospheric effects. Furthermore, the limited number of VIMS image cubes that have been analyzed have relatively low signal-to-noise. Finally, individual VIMS spectra often average together dune and inter-dune deposits due to limitations in spatial resolution. We propose a new approach to investigating Titan’s dune composition. In the proposed research, we will combine dune-fraction maps derived from RADAR data with atmosphere-corrected VIMS data, in order to extract the unique spectral signature of the dune material. Resulting spectra will be compared to those of candidate materials previously measured in the laboratory, and then will be mapped to units on Titan’s surface. The atmospheric correction has been successfully applied to several of Titan’s important geologic features, including Tui Regio and the ejecta of Sinlap crater (Hayne et al., 2013), but the dunes pose a challenge due to their sub-pixel scale in the VIMS data. Our approach will be to systematically derive atmosphere-corrected surface reflectance spectra at 2.0, 2.7, 2.8, and 5.0 m for all of the VIMS cubes publicly available on the Planetary Data System Figure 1. Comparison of dunes on Titan and Earth. The (PDS) that include dunes imaged dunes within the Belet region are morphologically distinct from those in Fensal, but are they compositionally distinct? From Le Gall et al. (2012) Jet Propulsion Laboratory Paul O. Hayne 1 Composition of Titan’s Dunes by RADAR. We will then apply linear and non-linear spectral mixtures analysis (McCord et al., 2008) to separate the contribution from the dunes, and map their compositional variations among Titan’s dune fields. 1.2 Background Sand dunes cover a significant portion (20%) of Titan’s equatorial regions (Figure 1) and represent a detailed geomorphic record of Titan’s climate and surface evolution. Previous studies of Titan’s dunes have focused on the spatial variation of observed dune morphologies and their interactions with local topography (e.g., Lorenz et al., 2006; Radebaugh et al., 2008, 2010). These studies have provided a basis for interpreting wind direction (e.g., Lorenz et al., 2006; Radebaugh et al., 2008; Rubin and Hesp, 2009, Savage et al., 2011) sediment supply (e.g., Radebaugh et al., 2010; LeGall et al., 2012) and atmospheric conditions, such as boundary layer depth (e.g, Lorenz et al., 2010) and aridity (e.g., LeGall et al. 2012, LeGall et al. 2013). What these previous studies have been unable to address, however, is what the dunes are made of. While dune particles are typically assumed to be derived from organic photolysis products (e.g., Lorenz et al. 2006), this has yet to be rigorously demonstrated from observation. We propose to combine the spatial resolution of the Cassini Synthetic Aperture Radar (SAR) (300 m/pixel) with the spectral information provided by VIMS to derive the composition of dune and interdune material. The results of the proposed study will be highly complementary to ongoing studies of dune morphology and spatial variation. Figure 1. Global mosaic of Synthetic Aperture Radar (SAR) observations of Titan in an equidistant cylindrical projection. SAR data is shown on top of a Visual Infrared Mapping Spectrometer (VIMS) basemap. Outlines for each of the major dune fields are shown. Note that dune field borders are not strictly defined and can vary from study to study. Previous work (Lorenz et al., 2006; Radebaugh et al., 2008) has identified dunes within all of the targeted study areas. 2 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes 2 Technical Approach and Methodology Our goal in analyzing the Cassini data is to isolate reflectance spectra of the dune materials from those of other geologic units, including the inter-dune material. The approach consists of four interrelated components: 1) Acquire relevant VIMS and RADAR data, and perform basic processing for use in the following steps 2) Apply atmospheric correction to VIMS reflectance data in order to derive a more accurate representation of true surface reflectivity spectra 3) Apply ‘de-noising’ algorithm to RADAR data and produce dune fraction maps coincident with VIMS reflectance maps 4) Isolate dune spectra through convolution of dune fraction with VIMS reflectance and linear un-mixing of VIMS end-member spectra Combining the results of these steps, we will compare the corrected dune (and interdune) spectra to those of materials known or expected to exist on Titan’s surface (e.g. H2O ice, complex hydrocarbon ‘tholin’, solid and liquid CH4 and C2H6, CO2 ice, NH3 ice). The final products will be compositional maps of the dune fields, and improved understanding of the nature and origins of the materials comprising the dunes. The following subsections describe each of the above components of the methodology in more detail. 2.1 Data Acquisition and Reduction All of the data needed to perform the proposed investigation are publicly available on the NASA Planetary Data System as of February 1, 2013. Each member of our team is experienced with one or both of the datasets, and is familiar with the calibration pipelines and post-processing steps required. In the process of preparing this proposal, we have already identified two key dune fields with geographically coincident (and high-quality) RADAR and VIMS data: Fensal (RADAR flyby T17, VIMS flyby T5 & T9), and Belet (RADAR flyby T8, VIMS flyby T79). Figure 2 shows the geographic location of the Belet ‘sand sea’ where the two datasets overlap. Because the RADAR data are typically acquired at much higher spatial resolution (300 m) than the VIMS data (>10 km), sub-pixel un-mixing is required to determine the contribution of the dunes to the Figure 2. Example complementary measured reflectance spectrum. Details of the datasets from RADAR and VIMS. Jet Propulsion Laboratory Paul O. Hayne 3 Composition of Titan’s Dunes approach are given in Section 2.4. VIMS Data The Visual and Infrared Mapping Spectrometer (VIMS) (Brown et al., 2004) consists of two spectrometer channels: the Visual channel covers the spectral range from about 0.35 to 1.05 µm and the IR channel covers the range from about 0.8 µm to 5.1 µm. Here will use only the IR channel data, where diagnostic molecular vibrational bands occur for the materials of interest. The pixel size can be as small as 0.25 x 0.5 mrad for the IR channel with nominal spectral sampling of 16.6 nm (256 bands). The nominal data set is an image cube consisting of two spatial dimensions (typically 64x64) and one spectral dimension. The data returned by VIMS consist of raw data numbers for each spectral channel at each spatial pixel. Each spectral channel is assigned a wavelength determined from the wavelength calibration, and the data numbers, once the dark and background signal have been subtracted, are multiplied by a radiometric response function for each pixel that relates raw instrument response to radiance. The radiometric response function is derived from measurements made on the ground before launch, enhanced with in-flight measurements of Venus, the Moon, Galilean satellites, and several stars (cf. McCord et al. 2004). Figure 3. T20 VIMS observations of Titan’s dunes in the Fensal region (60°W, 10°N). From Barnes et al. (2008). Typically, the dunes themselves are not resolved by VIMS, due to their narrow width (300 m – 1 km) and inter-dune spacing of 1-5 km (Neish et al., 2010; Le Gall et al., 2012), compared to typical surface resolutions of > 10 km. An important exception is the T20 (where “T_” refers to the Titan flyby number) “noodle”, with a spatial resolution of 500 m, comparable to that of the RADAR instrument (see below). Barnes et al. (2008) studied these data and performed an initial spectroscopic analysis of the dune and inter-dune materials (Fig. 3). As part of the proposed work, we will re-analyze these data, this time correcting for atmospheric effects (Section 2.2) in order to enable compositional analysis. We will also perform spectral mixtures analysis (Section 2.4) to extract the T20 dune spectra from those of the inter-dune materials. Many other lowerresolution, high signal-to-noise VIMS observations of Titan’s dune fields are available, but only a subset of these is spatially coincident with RADAR data. So far, we have 4 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes identified the T5 and T9 (Fensal), and T79 (Belet) as particularly promising. As part of this research, we will comb through the VIMS data for any other useful (exposure time > 80 ms, airmass < 3.0) dune field observations, though the aforementioned two datasets are sufficient for accomplishing the proposed tasks. RADAR Data In the proposed investigation, we will utilize Cassini RADAR data acquired in SAR imaging mode (Elachi et al., 2004). In this mode, topography is revealed by variations in apparent reflectivity due to surface slopes relative to the angle of incidence. Thus, the dunes appear as alternating bright/dark pairs and are easily identified in the SAR images. From these basic data, dunes will be mapped using an automated algorithm and by hand, as described in Section 2.3. 2.2 Atmospheric Correction to VIMS Data Figure 4. Example modeled and measured VIMS reflectance spectra of Titan. The thin solid line is a spectrum of Enceladus (mostly water ice) mixed with a neutral component with 2% reflectivity at all wavelengths, displaying a strongly negative slope from 2.7 to 2.8 m wavelength. When the darkened Enceladus spectrum is placed under a simulated Titan atmosphere (dashed line), it appears very similar to the actual measured Titan reflectance spectrum (thick solid line). In contrast, a neutral (2% reflectance) material under the same atmosphere (dotted line) is distinct from the measured Titan spectrum. From Hayne et al. (2013) Jet Propulsion Laboratory Titan’s surface is obscured by a thick absorbing and scattering atmosphere, allowing direct observation of the surface within only a few spectral windows in the nearinfrared (Sotin et al., 2005; McCord et al., 2006). Even within Titan’s near-IR methane windows, radiance measurements contain significant contributions from diffusely scattered radiation, especially at large phase angles. In a recent publication (Hayne et al., 2013), we developed a simple radiative transfer model, constrained by VIMS solar occultation data, which can be applied to remove atmospheric effects from reflectance measurements of Titan’s surface. Here, we briefly summarize this model and its applicability to the proposed research. Accounting for multiple reflections between the atmosphere and surface, the reflectance measured at the top of the atmosphere is then Paul O. Hayne 5 Composition of Titan’s Dunes R = Ra + RsTaTa* + Rs2 RaTaTa* + = Ra + Rs (1) TaTa* 1- Rs Ra where Ra is the reflectance of the atmosphere alone, Rs is the surface reflectance, Ta and Ta* are the transmission functions for the atmosphere from above and below, respectively (Liou, 2002, p. 365). The two terms in this equation represent the direct and diffuse radiation fields, respectively. Under the approximation of an optically thin, single-scattering atmosphere within the methane windows, equation (1) becomes R = Rs e-t 0m¢ + v0P 1- e-t m¢ . 4 ( m0 + m ) ( 0 ) (2) where m and m0 are the cosines of the solar incidence and emergence angles (provided in the VIMS backplanes), v 0 is the combined single scattering albedo of the haze particles and gas molecules, and P = P( m0 , m ) is the scattering phase function (normalized to unity). Inverting this equation leads to an expression for the surface reflectance, given the measured reflectance I / F , and the given photometric angles: Rs = ( I / F ) et 0m¢ + v0P 1- et m¢ . 4 ( m0 + m ) ( 0 ) (3) The coefficient of the second (diffuse) term can be found by fitting Titan’s reflectance as the airmass grows large, when the surface is no longer visible and the haze reflectance dominates, v0P (4) R» , for t 0 m ¢ 1. 4 m0 + m ( ) This is the so-called atmospheric “path radiance” (Kaufman, 1993). We assume a ( standard Henyey-Greenstein phase function, P(Q) = 1- g 2 ) (1+ g 2 - 2g cosQ ) 32 , and fit the VIMS reflectance data for 5.0 to determine the single scattering albedo 0 and the asymmetry parameter, g . Combining all data for the region 90-135W and 030N corresponding to Xanadu, we find best fit values at 2.8 m of g 0.4 and 0 0.3, consistent with the results of Coustenis et al. (2006) for the 3-micron spectral region (cf. West et al., 2005). For the 5-m window, we find best-fit values of g 0.4 and 0 0.2. Equation (3), with the normal optical depths 0 ( ) derived from the occultation measurements, provides a general atmospheric correction for the measured reflectance within the methane windows subject to the given model assumptions. In practice, the 6 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes 2.0, 2.7, 2.8 and 5.0-m windows are the cleanest, and therefore will be the focus of this investigation. The values of t 0 determined for these windows are approximately 0.4, 0.9, 0.2, and 0.1, respectively (Hayne et al., 2013). Figure 4 shows an example of modeled spectra near 2.8-m applied to match VIMS data for the Xanadu region. 2.3 Dune Mask from De-noised RADAR Data De-Noised SAR 0 0 dB 0 dB -15 dB -15 dB 5 10 20 30 40 0 km 5 Dune Mask No Dune 10 Dune 20 30 40 0 km 5 10 20 30 40 km Figure 5. Example SAR image of the Fensal dune field. A: Standard SAR image from the PDS B: De-Noised SAR image using the algorithm developed by Co-I Lucas C: Dune Mask generated using a threshold level of -8 dB. At this threshold level, dunes take up 32.4% of the area shown. In order to better constrain the composition of Titan’s dunes, we will utilize a dune fraction map, derived from publicly available Cassini RADAR backscatter data. We will derive these maps from de-noised SAR data (Lucas et al. 2011, 2012). Figure 5 shows the results of a simple thresholding algorithm applied to the de-noised data in the Fensal dune field. A classification algorithm (i.e., using ENVI software) has been used on the denoised T17 swath in order to extract a mask that indicates the location of dunes and inter-dunes as shown on Fig. 6. In the proposed work, we will project the highestresolution atmosphere-corrected VIMS cubes onto this and other dune fraction maps, to compute a weighted average spectrum of dune and non-dune pixels (Section 2.4). The creation of dune masks will be the primary responsibility of Co-I Hayes, Collaborator Lucas, and an undergraduate student supervised by Co-I Hayes. Below is the expected workflow for dune mask creation: PI Hayne and Co-I Combe will deliver the latitude and longitude boundaries of each pixel in a given VIMS spectral cube encompassing Titan’s dunes Co-I Hayes and the UG student will cross-reference each footprint against preexisting maps of the dune areas on Titan and keep only pixels that lie entirely on dune/interdune material (i.e., obstacle free). SAR images of dune-free areas that contain VIMS footprints will be sent to Co-I Lucas for de-noising, if necessary. For a subset of each observation, the student will manually determine dune/interdune fractions within each VIMS footprint in both the regular and denoised SAR data. These results will be used to validate the output of the automated classification algorithms. Jet Propulsion Laboratory Paul O. Hayne 7 Composition of Titan’s Dunes A simple thresholding algorithm (See Figure 5) will be applied to each de-noised image to determine dune/interdune fraction. The de-noised images will also be classified using the built-classifications algorithms available in the IDL ENVI software. The parameters of both the thresholding and ENVI classification algorithms will be adjusted to match the results of the manually determine dune/interdune fractions. Resulting dune/interdune fractions will be delivered to PI Hayne for use in the following tasks. Figure 6. Top: De-noised SAR data from Cassini RADAR, acquired on Titan flyby T17. Bottom: Dune mask created from the de-noised radar data, where white indicates dune material is present (see text for methodology). 2.4 Isolation of Dune Reflectance Spectra To constrain the composition of Titan’s dunes, we will generate corrected spectra from the highest- resolution VIMS cubes, taking an average weighted by the fractional area occupied by dunes, based on the RADAR dune mask (Section 2.3). This weighted-average spectrum will reduce the ambiguity in the spectra of the dune fields, where it is difficult to distinguish dune from inter-dune. Combined with the above steps, the procedure is as follows: 1) Perform atmospheric correction on VIMS data 2) Spatially co-register the VIMS and RADAR data 3) Assign a weight to each VIMS pixel based on the area fraction classified as dune material in the RADAR data 4) Calculate the average spectrum, weighted by the dune-fraction values Results of a pilot study are summarized in Figure 7. A complementary spectrum representing the inter-dune materials will also be calculated for each separate dune field. Variations among the dune field substrates may be related to their observed morphological differences (Le Gall et al., 2012). Where the signal-to-noise is high enough, we will also look at spectra of individual VIMS pixels where the dune fraction is determined to be > 50%. After this process, we will apply the Spectral Mixtures Analysis 8 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes (SMA) method to quantitatively separate the components making up the dune and inter-dune materials. Figure 7. Preliminary analysis of the co-registered VIMS spectral data in the Fensal dune field (CM_1514302990_1, upper left inset) and dune mask derived from RADAR data acquired on the T17 flyby. The lower left panel shows the ratio of the VIMS weighted average dune spectrum to the interdune weighted average spectrum. Differences of 5% in reflectivity are apparent, suggesting the dune spectra can be distinguished from inter-dune spectra. In the proposed research, we will quantify and map these compositional differences. Spectral Mixtures Analysis Spectral Mixing Analysis (SMA) techniques will be used to find compositional endmembers from the VIMS data, and correlate their contributions with the dune fraction map from RADAR. This approach is complementary to the weighted-average technique described above, rather than sequential. Comparing VIMS-derived mixing coefficient maps to the RADAR dune fraction maps will help us validate the approach and understand the different contributions to the dune field spectra. SMA methods are a well-established technique for separating linear (e.g. areal) mixtures of spectra (Adams and Gillespie, 2006), sharing similarities with the Principal Component Analysis (PCA) or Karhunen–Loève transformation (KLT) for data de- Jet Propulsion Laboratory Paul O. Hayne 9 Composition of Titan’s Dunes correlation and surface unit enhancement (Richards, 1994). The SMA method requires either the search of pixels corresponding to the purest composition within a scene (the spectral endmembers), or the use of reference spectra for which the composition is known, acquired in the laboratory. Taking the average reflectance at all the wavelengths as a reference, we fit the correlation trend of each wavelength by a straight line to the data spanning the largest and the smallest values. In order to retrieve potential additional spectral endmembers, we assume the spectra are mostly a linear mixture of the brightest and darkest components. If more than two spectral components can be detected, we remove the linear trend that fits the data in the two-dimensional scatter plots and then calculate the residual spectral shapes. These residuals are expected to be representative of spectra of other surface materials, or other effects from the atmosphere or the instrument. Relative abundances of surface materials can be retrieved by assuming that each observed spectrum is a linear combination of endmember spectra. In practice, we perform the SMA of VIMS data by using the Multiple-Endmember Linear Spectral Unmixing Model (MELSUM) (Combe et al., 2008). This model has been developed to account for mixtures and to map areal proportions of materials. The algorithm guarantees mixing coefficients to be strictly positive, and the sum of the fractions to equal unity. The spectral library of image endmembers is given as input for MELSUM. A spectrally neutral (flat), dark (set with zero values) endmember can be used to account for shading effects. Image fractions for all the image spectral endmembers are interpreted as contextual compositional maps of the main surface materials. For the present study, we will retrieve relative abundances of dune and inter-dune materials using the weighted average spectra (see above), and then also retrieve abundances using endmembers derived independently using the VIMS data alone. The latter can be correlated with the RADAR dune fraction maps to ensure that the compositional differences are in fact associated with the dune/interdune materials. 2.5 Composition After atmospheric correction and endmember extraction, the VIMS data give a more accurate representation of Titan’s surface spectral units, whose reflectivity is diagnostic of the materials’ composition and physical state (i.e. chemical makeup, solid or liquid phase, particle size). Uncertainties in reflectivity are determined by standard error propagation for each model parameter. In our pilot studies of the dune fields, we find uncertainties < 20% in surface reflectivity for the 2.0, 2.8, and 5.0-μm windows, with better precision at the longer wavelengths. We will compare corrected surface reflectivity values to simulated and laboratory-measured spectra of candidate materials for Titan’s dunes. Some materials for which we have optical constants include: water ice (Warren and Brandt 2008), alkanes (Clark et al. 2009), carbon dioxide ice (Hansen 1997), and “tholin” (e.g. Imanaka et al. 2012). Other possibilities will also be considered, including materials known to be present on other icy satellites (Dalton et al. 2010). To calculate reflectivity spectra (including non-linear mixtures), we utilize a standard deltaEddington model (Wiscombe and Warren, 1980), which accounts for multiple scattering 10 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes and absorption within particulate media with arbitrary grain size distribution (Hayne et al., 2012). Variations in reflectivity among the candidate materials are significantly larger than the uncertainties in the atmospheric correction, and the multi-dimensional spectral space allows even greater leverage on identification. 3 Perceived Impact Figure 8. High-resolution reflectance spectra compared This investigation into the to atmosphere-corrected VIMS spectra of three surface composition of Titan’s dune fields features. The dune field spectrum (in the Shangri-La has fundamental importance for the region) averages both dune and inter-dune materials. understanding of Titan’s geological evolution and the processes shaping the surface. Dunes represent a link between the geology and the recent climate, through the active redistribution of granular materials under dry, desert-like conditions. Hypotheses concerning the origin of the particles making up the dunes can be directly tested through knowledge of their composition. For example, inter-particle cohesion is strongly dependent on composition, which may therefore distinguish between merger/growth and breakup/erosion formation mechanisms (Aharonson et al., 2012). Furthermore, if the dunes are in fact composed of hydrocarbons precipitated from the atmosphere, they may represent the largest known reservoir of such materials on Titan (Le Gall et al., 2011), which has important implications for the moon’s evolving climate (Lorenz, 1996). Up to now, very little work has been done to rigorously constrain the composition of Titan’s dunes using the VIMS data, due to the typically coarse spatial resolution relative to the dune scale. The results of this study will therefore fill a critical gap in understanding, by leveraging the spatial resolution of the RADAR data and the spectral information contained in the VIMS data. Our results will inform future observational investigations using more sophisticated techniques, as well as theoretical studies of the origins, formation, and transport of Titan’s dune material. Another benefit to the community will be the availability of the dune mask data for future investigations. 4 Relevance This research will contribute to the main purposes of CDAPS, as described in ROSES 2013 in that it will “enhance the scientific return of the Cassini mission by broadening scientific participation in the analysis and interpretation of the data returned by the mission.” It also will contribute to NASA’s intent to plan, develop and fly new Outer Solar System missions, such as to Titan. Both the knowledge gained by this Jet Propulsion Laboratory Paul O. Hayne 11 Composition of Titan’s Dunes proposed research and the new young scientists educated by this effort will directly support new NASA mission development to Titan. The proposal topic and expected results are very relevant to the most recent roadmap recommendations by the NRC “Vision and Voyages for Planetary Science in the decade 2013-2022.” For example the Priority Questions and all three Crosscutting Themes (3-1) are addressed in that Titan’s composition and the processes altering it yields information on each: “Building New Worlds—understanding solar system beginnings, Planetary Habitats—searching for the requirements for life, and Workings of Solar Systems— revealing planetary processes through time.” Titan is specifically addressed in Section 8: Active Worlds and Extreme Environments. Further, the most recent document states that “All three of the crosscutting science themes for the exploration of the solar system motivate further exploration of the outer planet satellites,” especially Titan. Finally, the effort has a major educational aspect in that it will significantly contribute to the career development of two early-career Ph.D. scientists (PI Hayne, Co-I Hayes, and Co-I Combe) and further acquaint them with Cassini and the NASA research community, programs and missions in general. 5 Work Plan 5.1 Key milestones for accomplishments 5.1.1 First year We will acquire and process the Titan VIMS data (Hayne, Combe, Barnes), as well as the RADAR data (Hayes, Lucas) for selected regions of interest, notably the Belet and Fensal ‘sand seas’. From these data, classification maps of dune and inter-dune will be generated (Lucas, Hayes/student). After applying and validating the atmospheric correction to the VIMS data (Hayne), we will use the corrected VIMS data along with our established spectral mixture analysis (SMA) technique to derive the dune spectra and map surface constituents (Combe). In the first year, we will make preliminary comparisons to specific candidate molecules and mixtures suspected to compose the dunes (McCord, Hayne, Barnes, Sotin, Aharonson, Hayes). These results will be written up and presented at the LPSC conference in The Woodlands, TX, after then end of the first year. 5.1.2 Second year In the second year, we will shift focus to the spectral analysis (Combe, Hayne), while continuing to incorporate newly available data (Hayne, Hayes, Lucas) and improve the atmospheric correction (Hayne). Accurate dune and inter-dune spectra will enable quantitative comparison with candidate materials (McCord, Barnes, Hayne, Sotin, Aharonson). We will also investigate similarities and differences in composition among the different dune fields (All). At least one publication in a major journal will result from the two years of effort. We will also make the dune masks and resulting dune and inter- 12 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes dune VIMS spectra available to other researchers, through either the NASA PDS or supplementary materials of our publications, whichever is deemed appropriate. 5.2 Management structure and role of personnel We have assembled the proposing interdisciplinary team and have constructed and utilized custom designed data processing and analysis systems to specifically analyze the VIMS spectral data and the RADAR data. The team includes (1) very experienced scientists familiar with the VIMS IR data and (2) several young scientists developing their careers. Each team member has an extensive track record of productivity, and each has made major contributions to the science of Titan in the past. We also bring to bear young, well-qualified scientists who are not members of the Cassini teams or the Cassini Data Analysis Program (CDAP). Our efforts will provide a base of results that will enable a much broader community of scientists to use the VIMS data, because these data, although powerful, are not easily utilized. An important aspect of the proposed research is the participation of an undergraduate student (supervised by Co-I Hayes and PI Hayne) in mapping dunes using the Cassini RADAR dataset. PI Paul Hayne will lead the scientific efforts of the proposed investigation. He will also contribute his knowledge and understanding of spectral analysis and noise statistics, gained partly through his active role over the past several years in VIMS Titan data analysis. He has led recent attempts to demonstrate the value of solar occultations by VIMS for surface composition analysis and has published the results in the peerreviewed literature. Co-I Alexander Hayes will lead the RADAR data analysis and dune mapping. Dr. Hayes is a recognized expert on these data and the geological evolution and present state of Titan, in general. He will also co-advise a summer undergraduate student based at Cornell University, who will learn to use existing software to identify and map dune and inter-dune materials on Titan’s surface. Co-I Jean-Philippe Combe will focus on VIMS IR spectral image analysis using the various methods and tools, especially Spectral Mixing Analysis and his additional technique developments. Dr. Combe will also apply his extensive experience with VIMS image data and their manipulation using ENVI as well as other mission spectral imagery, including for his Ph.D. dissertation research (Combe 2005). Co-I Thomas McCord will apply his extensive experience in the physics of planetary solid-state materials, spacecraft and laboratory experimental studies, data analysis, with space missions and in particular his recent experience analyzing Titan surface composition, and with mentoring young scientists. Dr. McCord has extensive experience over 40 years processing and analyzing telescopic and spacecraft spectroscopic data and leading group efforts to study planetary objects including for VIMS and Titan. He has been consistently very productive, as his publications indicate. Collaborator Jason Barnes has published numerous papers on the surface composition, morphology, and geologic history of Titan, primarily using the VIMS Jet Propulsion Laboratory Paul O. Hayne 13 Composition of Titan’s Dunes dataset. Dr. Barnes will assist in the acquisition of appropriate datasets, spectral analysis, and interpretation of results. Collaborator Christophe Sotin has extensive experience with the VIMS Titan measurements (having designed many of the observations), and will aid in their interpretation. Collaborator Antoine Lucas has expertise in processing RADAR data, and will generate masks of the dunes for comparison with VIMS. Collaborator Oded Aharonson has wide ranging expertise on the geophysics, climate, and active processes shaping the surface of Titan, as well as RADAR data, and will consult primarily on the interpretation of the compositional data. Table: Summary of tasks and description of efforts (working months *) for all team members Description of Effort Task 1 Obtain and process VIMS and RADAR data Task 2 Apply atmospheric correction to VIMS data Team member Year 1 Year 2 Total P. Hayne 0.25 0.25 0.50 J-P. Combe 0.05 0.00 0.05 A. Hayes 0.10 0.05 0.15 J. Barnes 0.10 0.00 0.10 A. Lucas 0.15 0.15 0.30 P. Hayne 1.00 0.75 1.75 A. Hayes Task 3 Apply de-noising algorithm and classify dune material in A. Lucas RADAR data O. Aharonson 0.25 0.20 0.45 0.25 0.25 0.50 0.05 0.05 0.10 P. Hayne 1.00 0.50 1.50 J-P. Combe 0.50 1.00 1.50 Task 4 Isolate dune and inter-dune spectral components, T. McCord 0.05 0.05 0.10 perform SMA J. Barnes 0.10 0.05 0.15 C. Sotin 0.05 0.05 0.10 P. Hayne 0.25 1.00 1.25 T. McCord 0.20 0.20 0.40 Task 5 A. Hayes 0.05 0.05 0.10 Compare dune and inter-dune spectra with candidate C. Sotin 0.20 0.20 0.40 materials, produce maps O. Aharonson 0.05 0.05 0.10 J. Barnes 0.05 0.20 0.25 P. Hayne 2.50 2.50 5.00 J-P. Combe 0.55 1.00 1.55 TOTAL (those requesting funding only) A. Hayes† 0.40 0.30 0.70 T. McCord 0.25 0.25 0.50 *Note: Hours listed for Collaborators (gray) are funded by other sources. Dr. Aharonson and Dr. Sotin are funded by the Cassini science investigation, and Dr. Lucas is funded at the University of Paris. Dr. Barnes is funded by the University of Idaho for 9 months per year, with 60% time devoted to scholarly activity such as the proposed work. † Much of the effort allocated to Dr. Hayes will be performed by an undergraduate student. 14 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes APPENDIX: PARTICIPATING SCIENTIST REQUEST Abstract: The proposed research will benefit through PI Paul Hayne serving as Cassini Participating Scientist by: 1) enhancing the geographic coverage of the atmosphere-corrected VIMS reflectance observations of Titan’s surface; 2) affording closer collaboration with key VIMS science team members experienced in the study of Titan’s surface composition; 3) improving the atmospheric correction by expanding the number of available observations and viewing geometries. In addition, Dr. Hayne brings expertise and capabilities in several areas complementary to the present VIMS science team, including atmospheric radiative transfer and albedo modeling of granular mixtures. A.1 Objectives and Expected Contributions Study of Titan’s surface composition using VIMS hinges on the accurate interpretation of near-infrared reflectance spectra, which are known to be contaminated by scattering and absorption in the atmosphere. The VIMS science team has explored several techniques for accounting for these atmospheric effects, but no standard correction has yet emerged. In the attached CDAPS proposal, we described a method leading to a simple, yet accurate atmospheric correction to the VIMS reflectance spectra of Titan’s surface. In this appendix we describe how this research will benefit from Science PI Paul Hayne serving as a Cassini Participating Scientist. This role will allow greater interaction with the Cassini science team and enable access to critical datasets needed in order to maximize the usefulness of the proposed investigation. Dr. Hayne’s extensive experience in analyzing VIMS Titan reflectance and occultation data, as well as expertise in radiative transfer theory, will complement the existing strengths of the VIMS science team and further the goals of the Cassini Solstice Mission (CSM). A.1.1 Science background and objectives In the attached proposal, we provided the science justification for the proposed investigation; here we highlight some of the outstanding issues motivating participation in the PS program. Geologic units on Titan’s surface have been mapped in some detail using VIMS and other Cassini instruments (notably RADAR and ISS), yet their surface composition remains ambiguous. Ground truth measurements from the Huygens GCMS revealed an assortment of volatiles, including hydrocarbons likely precipitated from the atmosphere (Niemann et al. 2010). Water ice – likely the bulk crustal component – was evidently observed by the descent imager/spectral radiometer (DISR) in the floodplain where Huygens touched down (Keller et al. 2008). Despite this observation, and evidence from ground-based telescopes (Griffith et al. 2003), no large scale exposures of pure water ice have been definitively identified so far using VIMS, although water ice mixtures are possible (McCord et al. 2007). Soderblom et al. (2007) noted discrepancies in the boundaries of geologic units mapped using VIMS and RADAR, suggesting the Jet Propulsion Laboratory Paul O. Hayne 15 Composition of Titan’s Dunes presence of a thin mantling unit of atmosphere-derived hydrocarbons, which is somewhat transparent at radar wavelengths (of order centimeters). However, this model has yet to be rigorously tested with atmosphere-corrected spectra. The vast equatorial dune fields are spectrally more neutral in the near-IR than other surface units, consistent with the hypothesis that the grains are composed of a tholinlike substance formed through photochemical reactions in the atmosphere and precipitated to the surface (Barnes et al. 2008). This interpretation is broadly consistent with RADAR scattering cross sections near those of porous solid hydrocarbons, but the measurements are also consistent with solid CO2 (Zebker et al. 2008). Benzene, simple alkanes and nitriles have been reported recently by Clark et al. (2010), though the low signal-to-noise ratio of VIMS observations in the 5-m window makes mapping their distribution on Titan’s surface challenging. Especially interesting is the identification of liquid ethane in one of Titan’s south polar lakes (Ontario Lacus; Brown et al. 2008), an observation that might be repeated for the north polar lakes as the sun illuminates them during the CSM. Some fluvial features (e.g. channels and floodplains) are spatially resolved at the sub-kilometer scale by VIMS (Jaumann et al. 2008), such that accurate reflectance measurements could provide insight into Titan’s unique “methanological” cycle. We will be especially interested in identifying any compositional changes resulting from active weather systems (Turtle Figure A1. False-color (R=5.0 m, G=2.0m, et al. 2011). Finally, putative cryovolcanic B=1.6m) VIMS images of (A) Tui Regio, and (B) Hotei Regio (bright feature at limb), and (C) 4.92features (notably Hotei Regio) must be tested m band depth (left panel) and 2.8/2.7-m for compositional characteristics consistent reflectance ratio (right panel) for Tui Regio. with an endogenic origin, which has so far not been demonstrated. As a Participating Scientist, Dr. Hayne will address these ambiguities in the present understanding of Titan’s surface composition as an expression of the underlying geology, by working with the VIMS team to develop and apply a simple and accurate method of atmospheric correction for the Titan reflectance measurements. Selection for this program will improve the outcome of the proposed investigation in the following ways: 1) Geographic coverage (particularly in longitude) of the corrected Titan reflectance measurements will be greatly expanded through the use of more recent proprietary data; 2) Analysis of occultation data will be more rapid and potentially more accurate, owing to the unique knowledge of these sequences by the VIMS team (e.g. Dr. Christophe Sotin, a collaborator on this proposal); 3) Interpretation and mapping of compositional units on Titan’s surface will greatly benefit from the collective experience of the VIMS science team in remote reflectance spectroscopy and icy satellite geology. The expanded geographic coverage will also allow improvements in the atmospheric 16 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes correction derived from on-planet reflectance measurements (Section 2.3.2), and aid in estimating errors associated with temporal variations in atmospheric properties. A.1.2 Capabilities and Qualifications As a Participating Scientist, Dr. Hayne will bring complementary capabilities to the science team, in addition to a wealth of experience analyzing VIMS observations of Titan. These capabilities include: 1) An atmospheric radiative transfer model developed for the calculation of infrared scattering and absorption by aerosols, and 2) a surface reflectance model allowing mixtures of two or more constituents. Each of these is described below. Experience with VIMS data The team of investigators on this proposal has been studying Titan with VIMS for over five years, and has developed specialized software and other tools specifically for analyzing this dataset. Dr. Hayne has led several focused efforts, including a substantial portion of the work leading to the McCord et al. (2007) paper, which delineated the compositional endmembers of Titan’s surface and mapped their distribution. He developed a set of IDL routines for finding and measuring narrow absorption features within the methane windows, which led to the discovery that the (so far unidentified) 4.92-m absorption feature is strongly correlated with the anomalous bright features Tui and Hotei Regio, which have been suggested to be cryovolcanic features (Figure A1). Without atmospheric correction, the VIMS reflectance data can only be used to infer relative compositional differences (i.e. absolute reflectance is poorly constrained, but ratios are meaningful). In this way, we deduced that if water ice is present on the surface of Titan, these anomalous geologic features must be depleted in H 2O relative to the average Titan terrain, perhaps placing constraints on the composition of the putative cryolava (Hayne et al. 2008). In fact, the ammonia hydrate cryolava preferred by most models for eruptive volcanism on icy satellites (Kargel 1994) is not consistent with the compositional differences we inferred from the VIMS data, suggesting further work is needed to confirm or disprove cryovolcanism as the formation mechanism for Tui and Hotei Regio. So far, only one of the Titan solar occultations has been analyzed in detail, which was used to infer atmospheric properties (Bellucci et al. 2009). Clark et al. (2010) also used one of the occultations to derive a first-order correction to the 2.8/2.7-m ratio. Dr. Hayne has extensive experience with these observations, and has already made significant progress in calculating atmospheric transmission spectra for each of the high quality solar occultations (Hayne and McCord 2009). This is a unique capability that he will bring to the science team, while at the same time learning from those who originally designed the observation sequences. He also brings a demonstrated track record collaborating with the VIMS science team, for example contributing to the paper describing the VIMS Titan dataset (Barnes et al. 2009). Atmospheric radiative transfer While a graduate student at UCLA, Dr. Hayne developed a radiative transfer model for the calculation of intensities in the cloudy polar atmosphere of Mars (Hayne Jet Propulsion Laboratory Paul O. Hayne 17 Composition of Titan’s Dunes 2010; Hayne et al, 2012). This model, based on a two-stream -Eddington approximation for multiple scattering in an inhomogeneous atmosphere, is extremely efficient and has been shown to be accurate under a range of realistic planetary conditions within ~1% in radiance in the mid-infrared. The model was designed using a modular approach, so that the source function can be swapped in and out depending on the application; for instance, solar versus thermal radiation. The internal radiation field is calculated assuming a plane parallel atmosphere, but spherical geometry is employed in integrating the formal solution along an arbitrary path, such that any viewing geometry is allowed with consistent accuracy. This model has direct applicability to calculating intensities including scattering by Titan’s aerosols in the near-IR wavelengths covered by VIMS. We have begun preliminary discussions with VIMS associate Dr. Jason Barnes (U. Idaho) and various VIMS team members about incorporating this model in simulating atmospheric scattering, and correcting surface reflectance data under a variety of illumination and viewing conditions. Involvement as a Cassini PS would allow closer collaboration and development of this model in order to improve Titan surface science. Granular surface reflectance model We also have extensive experience in simulating the reflectivities of granular mixtures, based on the snow albedo model of Wiscombe and Warren (1980), and using scattering parameters calculated from Mie theory (e.g. Hansen and Travis 1974). Given optical constants of candidate materials on Titan’s surface, we calculate theoretical reflectance spectra of the pure substances and mixtures, which can then be compared to VIMS observations after atmospheric correction. For instance, mixtures of water ice and solid hydrocarbons might match the reflectance spectra of Titan’s equatorial dunes (Barnes et al. 2008) – a hypothesis we can readily test with this model and the atmosphere-corrected VIMS data (cf. Hayne 2010). A.2 Relevance to Cassini Science Goals The proposed investigation will address the surface composition of Titan, the distribution of geologic units, as well as their origin and subsequent modification. Interpreting any surface changes occurring during the CSM will rely on accurate compositional information. For instance, changes in methane concentration in the very near-surface pore space (cf. Niemann et al. 2005) due to seasonal transport or sudden rainstorms (Turtle et al. 2011) might have a subtle, yet measurable effect on surface reflectance. Quantifying these changes will require accurate atmospheric correction, as proposed here. More specifically, the proposed investigation, and Dr. Hayne’s involvement as a Cassini PS will address the “Cassini Solstice Mission Science Objectives: Prioritized Summary” goal TN1a: “Determine the types, composition, distribution, and ages, of surface units and materials, most notably lakes (i.e. filled vs. dry & depth; liquid vs. solid & composition; polar vs. other latitudes & lake basin origin).” 18 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes A.3 Collaborations with the Cassini Science Team The primary collaboration will be with the VIMS team, though other datasets, notably RADAR and ISS may prove to be complementary. For example, dielectric properties inferred from RADAR can be compared with those from VIMS in order to place better constraints on surface composition and subsurface structure (e.g. Tosi et al. 2010). After deriving and mapping atmosphere-corrected surface reflectance, Dr. Hayne will make these maps available first to the Cassini science team for interpretation and further refinement. Several investigators on the VIMS science team, in addition to Dr. McCord, have expertise on Titan’s surface composition, notably Dr. Lawrence Soderblom, Dr. Roger Clark, and Dr. Christophe Sotin. These will be the primary collaborators with whom Dr. Hayne will work as a Cassini PS, and he has already collaborated to some degree with each of them on related topics. Determining Titan’s surface composition is an immensely challenging problem, involving a wide range of disciplines and observation techniques; expanding the cohort of investigators (especially to those beginning their careers) will advance this endeavor greatly. A.4 Compliance with Cassini Rules As a member of the Cassini science team, Dr. Hayne will comply with all aspects of the “Rules of the Road Science Policy Document”, as well as any team-specific guidelines. Jet Propulsion Laboratory Paul O. Hayne 19 Composition of Titan’s Dunes References Adams, J. B. and A.R. Gillespie (2006), Remote Sensing of Landscapes with Spectral Images: A Physical Modeling Approach. Cambridge University Press. 362pp. Baines, K.H., Brown, R. H., Cruikshank, D.P., Clark, R.N., Nelson, R.M., Matson, D.L., Buratti, B.J., Carusi, A., Coradini, A., Bibring, J.P., Sotin, C., Langevin, Y., Jaumann, R., Formisano, V., Combes, M., Drossart, P., Langevin, Y., Sicardy, B., 1992. VIMS/Cassini, at Titan: scientific objectives and observational scenarios. In: Symposium on Titan, Conference Proceedings, ESA SP 338, pp. 215– 219. Barnes, J. W. et al. (2008) "Spectroscopy, morphometry, and photoclinometry of Titan's dunefields from Cassini/VIMS" Icarus 195, 400-414. Barnes, J. W. et al. (2009) "VIMS spectral mapping observations of Titan during the Cassini prime mission" Planetary and Space Science, Volume 57, Issue 14-15, p. 1950-1962. Bellucci, A. et al. (2009), Titan solar occultation observed by Cassini/VIMS: Gas absorption and constraints on aerosol composition, Icarus 201, 198-216. doi:10.1016/j.icarus.2008.12.024Boardman, J. W., Kruse, F. A., and Green, R. O., 1995, Mapping target signatures via partial unmixing of AVIRIS data: in Summaries, Fifth JPL Airborne Earth Science Workshop, JPL Publication 95-1, v. 1, pp. 23-26. Brown, R. H., Baines, K.H., Bellucci, G., Bibring, J.P., Buratti, B.J., Bussoletti, E., Capaccioni, F., Cerroni, P., Clark, R.N., Coradini, A.,Cruikshank, D.P., Drossart, P., Formisano, V., Jaumann, R., Langevin, Y., Matson, D.L., McCord, T.B., Mennella, V.,Miller, E.,Nelson, R.M., Nicholson, P.D., Sicardy, B., Sotin C., 2004. The Cassini Visual and Infrared Mapping Spectrometer Investigation. Space Sci. Revs., 115, 111168. Brown, R. H. et al. (2008), The identification of liquid ethane in Titan's Ontario Lacus, Nature 454, 607- 610. doi:10.1038/nature07100 Clark, R. N., J. M. Curchin, R. H Brown, J. H. Waite, D. P. Cruikshank, R. Jaumann, J. Lunine, T. M Hoefen, T. E. Cravens, R. V. Yelle, V. Vuitton, K. H. Baines, B. J. Buratti, J. Barnes, T. B. McCord, P. D. Nicholson, 2006a. Detection of widespread aromatic and aliphatic hydrocarbon deposits on Titan’s surface observed by VIMS and excess benzene observed in Titan’s thermosphere observed by INMS, Bull. Am Ast. Soc., 38, 3, 574. Abst 48-04. Clark, R. N., J. M. Curchin, R. H Brown, D. P. Cruikshank, R. Jaumann, J. Lunine, T. M Hoefen, K. H. Baines, B. J. Buratti, J. Barnes, P. D. Nicholson, 2006b. Detection of widespread aromatic and aliphatic hydrocarbon deposits on Titan’s surface observed by VIMS, Am. Geophys U. annual fall meeting proceedings, p. 21, Abst P11A-03. Clark, R. N. et al. (2010) "Detection and mapping of hydrocarbon deposits on Titan" Journal of Geophysical Research 115, E10005 Combe J.-Ph., 2005, Etudes des surfaces planétaires par télédétection visible infrarouge hyperspectrale, PhD thesis, Université de Nantes, 300p 20 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Combe, J.-Ph.; Le Mouélic, S.; Sotin, C.; Gendrin, A.; Le Deit, L.; Mustard, J. F.; Bibring, J.P.; Gondet, B.; Langevin, Y.; Omega Science TeamAnalysis of OMEGA/Mars Express Hyperspectral Data Using a Linear Unmixing Model: Methods and Preliminary Results, abstract no. 2115, 37th LPSC, 13-17 March 2006. Combe J.-Ph., Le Mouélic S., Sotin C., Gendrin A., Mustard J. F., Le Deit L., Launeau P., Bibring J.-P., Gondet B., Langevin Y., Pinet P., and the OMEGA Science team, Analysis of OMEGA / Mars Express data hyperspectral data using a Multiple-Endmember Linear Spectral Unmixing Model (MELSUM): Methodology and first results, Planetary and Space Science, 2008, vol 56/7, 951-975, doi: 10.1016/j.pss.2007.12.007. Coustenis, A., Lellouch, E., Maillard, J.P., McKay, C.P., 1995. Titan’s surface: composition and variability from the near-infrared albedo. Icarus 118, 87–104. Coustenis, A., A. Negrão, A. Salama, B. Schulz, E. Lellouch, P. Rannou, P. Drossart, T. Encrenaz, B. Schmitt, V. Boudon and A. Nikitin, 2006, Titan's 3-micron spectral region from ISO high-resolution spectroscopy. Icarus, 180, Pages 176-185 Flasar, F.M., 1983. Oceans on Titan? Science 221, 55–57. Flasar, F. M., et al., 2005. Titan’s atmospheric temperatures, winds, and composition. Science 308, 975- 978. Fulchignoni, M., Ferri, F, Colombatti, G., Zarnecki, J. C., Harri, A-M., Girard, R., Schwingenschuh, K., Hamelin, M. Lopez Moreno, J.J., Svedhem, H., the HASI team, 2005. First results on the characteristics of Titan’s atmosphere by the Huygens Atmospheric Structure instrument 9HASI) measurements. European Geophysical Union Abstract -A-05792; US9/PS1.5-1MO1O-006. Griffith, C.A., Owen, T., Wagener, R., 1991. Titan’s surface and troposphere, investigated with groundbased, near-infrared observations. Icarus 93, 362–378. Griffith, C.A., 1993. Evidence for surface heterogeneity on Titan. Nature 364, 511–514. Griffith, C. A., Owen, T. , Geballe, T. R. , Rayner, J., Rannou, P., 2003. Evidence for the exposure of water ice on Titan’s surface. Science 300, 628-630. Hansen, G. B., T. B. McCord, C. A. Hibbitts, and L. W. Kamp, 2006. Progress on the recalibration and rectification of Galileo NIMS spectral images of the Galilean satellites (abstract), Eos Trans. AGU, 87(36), Jt. Assem. Suppl., Abstract P41B-05. Hapke, B., Theory of Reflectance and Emittance Spectroscopy, Cambridge University Press, 455 pp., 1993. Hayne, P. et al. (2008), Titan: Observational Constraints on Cryovolcanism. Lunar and Planetary Science XXXIX, p. 2010. Hayne, P. O. et al. (2009), Titan's Near Infrared Atmospheric Transmission and Surface Reflectance from the Cassini Visual and Infrared Mapping Spectrometer, Lunar and Planetary Science XL. Hayne, P. O., 2010. Snow Clouds on Mars and Ice on the Moon: Infrared Observations and Models, PhD thesis, University of California, Los Angeles, 227 pp. Hayne, P. O., D. A. Paige, J. T. Schofield, D. M. Kass, A. Kleinbohl, N. G. Heavens, and D. J. McCleese (2012), Carbon dioxide snow clouds on Mars: South polar winter observations by the Mars Climate Sounder, J. Geophys. Res., 117, E08014, doi:10.1029/2011JE004040. Jet Propulsion Laboratory Paul O. Hayne 21 Composition of Titan’s Dunes Hayne, P. O., T. B. McCord, and C. Sotin (2013), Titan’s surface composition: correction for atmospheric effects derived from near-infrared solar occultation measurements by Cassini-VIMS, Icarus, in press. Jaumann, R.; Stephan, K.; Brown, R. H.; Buratti, B. J.; Clark, R. N.; McCord, T. B.; Coradini, A.; Capaccioni, F.; Filacchione, G.; Cerroni, P.; Baines, K. H.; Bellucci, G.; Bibring, J.-P.; Combes, M.; Cruikshank, D. P.; Drossart, P.; Formisano, V.; Langevin, Y.; Matson, D. L.; Nelson, R. M.; Nicholson, P. D.; Sicardy, B.; Sotin, C.; Soderbloom, L. A.; Griffith, C.; Matz, K.-D.; Roatsch, Th.; Scholten, F.; Porco, C. C., 2006, High-resolution CASSINI-VIMS mosaics of Titan and the icy Saturnian satellites, Planetary and Space Science, 4, Issue 12, 1146-1155. Kargel, J. S. (1994) "Cryovolcanism on the icy satellites" Earth, Moon, and Planets 67, 101-113. Le Gall, A., Janssen, M. a., Wye, L. C., Hayes, A. G., Radebaugh, J., Savage, C., Zebker, H., et al. (2011). Cassini SAR, radiometry, scatterometry and altimetry observations of Titan’s dune fields. Icarus, 213(2), 608-624. Elsevier Inc. doi:10.1016/j.icarus.2011.03.026 Le Gall, A., Hayes, A. G., Ewing, R. C., Janssen, M. A., Radibaugh, J., Savage, C., Encrenaz, P., et al. (2012). Latitudinal and altitudinal controls of Titan’s dune fid morphometry. Icarus, 217, 231-242. doi:10.1016/j.icarus.2011.10.024. Liou, K. N. (2002), Introduction to Atmospheric Radiation, Academic Press, San Diego, 579 pp. Lorenz, R. D. 1996. Pillow lava on Titan: expectations and con- straints on cryovolcanic processes. Planet. Spac. Sci., 44, 1021–1028. doi: 10.1016/0032-0633(95)00139-5. Lorenz, R D, Wall, S., Radebaugh, J., Boubin, G., Reffet, E., Janssen, M., Stofan, E., et al. (2006). The sand seas of Titan: Cassini RADAR observations of longitudinal dunes. Science (New York, N.Y.), 312(5774), 724-7. doi:10.1126/science.1123257 Lorenz, R. D., & Radebaugh, J. (2009). Global pattern of Titan’s dunes: Radar survey from the Cassini prime mission. Geophysical Research Letters, 36(3), 9-12. doi:10.1029/2008GL036850. Lorenz, R. D., Claudin, P., Andreotti, B., Radebaugh, J., & Tokano, T. (2010). A 3km atmospheric boundary layer on Titan indicated by dune spacing and Huygens data. Icarus, 205(2), 719–721. doi:10.1016/j.icarus.2009.08.002. Lucas, A., O. Aharonson, A. G. Hayes, C. A. Deledalle, and R. L. Kirk (2011), Enhanced processing and analysis of Cassini SAR images of Titan, AGU Fall Meeting, abstract no. P33E-1795. Lucas, A., O. Aharonson, A. G. Hayes, C. Deledalle, L. Wye, R. Kirk, E. Howington-Kraus, and the Cassini RADAR Science Team (2012), Clues to Titan hydrology from enhanced SAR image processing, 43rd Lunar and Planet. Sci. Conf., The Woodlands, TX, abstract no. 1659. McCord, T. B., A. Coradini, C. A. Hibbitts, F. Capaccioni, G. b. Hansen, G. Filacchione, R. N. Clark, P. Cerroni, R. H. Brown, K. H. Baines, G. Bellucci, J.-P. Bibring, B. J. Buratti, E. Bussoletti, M. Combes, D. P. Cruikshank, P. Crossart, V. Formisano, R. Jaumann, Y. Langevin, D. L. Matson, R. M. Nelson, P. D. Nichoson, B. Sicardy, and C. Sotin, 2004. 22 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Cassini VIMS Global observations of the Galilean Satellites including the VIMS calibration procedure. Icarus, 172, 104-126. McCord, T. B., Hansen, G. B., Buratti, B. J., Clark, R. N., Cruikshank, D. P., D’Aversa, E., Griffith, C. A., Baines, E. K. H., Brown, R. H., Dalle Ore, C. M., Filacchione, G., Formisano, V., Hibbits, C. A., Jaumann, R., Lunine, J. I., Nelson, R. M., Sotin, C., and the Cassini VIMS Team, 2006a. Composition of Titan’s Surface from Cassini VIMS. Planetary and Space Science 54, 1524-1539. McCord, T. B., P. Hayne, J-P. Combe, G. B. Hansen, K. H. Baines, R. H. Brown, B. J. Buratti, R. N. Clark, P. Nicholson, 2006b. Titan surface composition analysis using VIMS, Bull. Am Ast. Soc., 38, 3, 574-575. Abst 48-05. McCord T. B., Hayne P. G., Combe J.-Ph., Hansen G. B., Barnes J. W., Rodriguez S., Le Mouélic S., Baines K. H., Buratti B. J., Sotin C., Nicholson Ph., Jaumann R., Nelson R., and the Cassini VIMS Team, Titan’s Surface: Search for spectral diversity and composition using the Cassini VIMS investigation, Icarus, 2007a, Volume 194, 212242, doi: 10.1016/j.icarus.2007.08.039. McCord, T. B., P. Hayne, J-P. Combe, G. B. Hansen, J. W. Barnes, B. Buratti, K. H. Haines, R. H. Brown, and P. Nicholson, 2007b, Titan: Surface composition from Cassini VIMS, European Geosciences Union General Assembly, Geophys. Res. Abst. ISSN: 10297006. McCord, T. B., P. O. Hayne, J.-P. Combe, and G. B. Hansen (2008), Titan: The case for CO2 on the surface, paper presented at EGU 2008 General Assembly, Geophysical Research Abstracts, Vienna, Austria, April 13-18, 2008, EGU2008-A-05368. McCord, T. B., and P. O. Hayne (2009), Nature of the 2.8-um window in Titan's atmosphere and effects on detection of surface reflectance characteristics, paper presented at European Planetary Science Congress, Potsdam, Germany, September 14-18, 2009. Le Mouelic, S. et al. (2010a), Empirical Approaches To Reduce The Atmospheric Component In VIMS Surface Images Of Titan, American Geophysical Union, Fall Meeting 2010, abstract #P31C-1546 Le Mouelic, S. et al. (2010), Imaging of Titan in the infrared with Cassini/VIMS : Toward homogeneous surface maps, EGU General Assembly 2010, held 2-7 May, 2010 in Vienna, Austria, p.8483 Lodders, K. and Fegley, B. (1998), The planetary scientist's companion. New York : Oxford University Press, 1998. QB601 .L84 1998Lunine, J.I., Stevenson, D.J., Yung, Y.L., 1983. Ethane ocean on Titan. Science 222, 1229. Neish, C. D., R. D. Lorenz, R. L. Kirk, and L. C. Wye (2010), Radarclinometry of the sand seas of Africa’s Namibia and Saturn’s moon Titan, Icarus, 208, 385-394, doi: 10.1016/j.icarus.2010.01.023. Niemann, H. B., S. K. Atreya, J. E. Demick, D. Gautier, J. A. Haberman, D. N. Harpold, W. T. Kasprzak, J. I. Lunine, T. C. Owen, R. Raulin, 2010, Composition of Titan’s lower atmosphere and simple surface volatiles as measured by the Cassini-Huygens probe gas chromatograph mass spectrometer experiment, J. Geophys. Res. 115, DOI: 10.1029/2010JE003659. Jet Propulsion Laboratory Paul O. Hayne 23 Composition of Titan’s Dunes Radebaugh, J., Lorenz, R. D., Lunine, J. I., Wall, S. D., Boubin, G., Reffet, E., Kirk, R. L., et al. (2008). Dunes on Titan observed by Cassini Radar. Icarus, 194(2), 690-703. doi:10.1016/j.icarus.2007.10.015 Radebaugh, J., Lorenz, R., Farr, T., Paillou, P., Savage, C., & Spencer, C. (2010). Linear dunes on Titan and earth: Initial remote sensing comparisons. Geomorphology, 121(1-2), 122-132. doi:10.1016/j.geomorph.2009.02.022 Rubin, D. M., & Hesp, P. a. (2009). Multiple origins of linear dunes on Earth and Titan. Nature Geoscience, 2(9), 653-658. Nature Publishing Group. doi:10.1038/ngeo610 Savage, C. J., & Radebaugh, J. (2011). Parameter analysis of Titan’s dunes reveals surface evolution history. Lunar and Planetary Science Conference XLII, (2261). Houston. Stofan, E. R.; Elachi, C.; Lunine, J. I.; Lorenz, R. D.; Stiles, B.; Mitchell, K. L.; Ostro, S.; Soderblom, L.; Wood, C.; Zebker, H.; Wall, S.; Janssen, M.; Kirk, R.; Lopes, R.; Paganelli, F.; Radebaugh, J.; Wye, L.; Anderson, Y.; Allison, M.; Boehmer, R.; Callahan, P.; Encrenaz, P.; Flamini, E.; Francescetti, G.; Gim, Y.; Hamilton, G.; Hensley, S.; Johnson, W. T. K.; Kelleher, K.; Muhleman, D.; Paillou, P.; Picardi, G.; Posa, F.; Roth, L.; Seu, R.; Shaffer, S.; Vetrella, S.; West, R., 2007, The lakes of Titan, Nature, 445, Issue 7123, 61-64, 10.1038/nature05438 Tobie, G., Grasset, O., Lunine, J., Mocquet, A., Sotin, C., 2005. Titan’s internal structure inferred from a coupled thermal-orbital model. Icarus 175, 496–502. Tomasko, M.G., Archinal, B., Becker, T., Be ́ zard, B., Bushroe, M., Combes, M., Cook, D., Coustenis, A., de Bergh, C., Dafoe, L.E., Doose, L., Doute , S., Eibl, A., Engel, S., Gliem, F., Grieger, B., Holso, K., Howington-Kraus, E., Karkoschka, E., Keller, H.U., Kirk, R., Kramm, R., Kuppers, M., Lanagan, P., Lellouch, E., Lemmon, M., Lunine, J., McFarlane, E., Moores, J., Prout, G.M., Rizk, B., Rosiek, M., Rueffer, P., Schro d ̈ er, S.E., Schmitt, B., See, C., Smith, P., Soderblom, L., Thomas, N., West, R., 2005., Rain, winds and haze during the Huygens probe’s descent to Titan’s surface", Nature 438 (7069), 765–778 Turtle, E. P. et al. (2011) "Rapid and Extensive Surface Changes Near Titan's Equator: Evidence of April Showers" Science 331, 1414. Yung, Y. L.; Allen, M.; Pinto, J. P., 1984, Photochemistry of the atmosphere of Titan Comparison between model and observations, Astrophysical Journal Supplement Series, vol. 55, 465-506, 10.1086/190963 24 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Biographical Sketches Paul Ottinger Hayne Geophysics and Planetary Geosciences Section Jet Propulsion Laboratory, California Institute of Technology MS 183-301, Pasadena, CA 91109 Paul.O.Hayne@jpl.nasa.gov T: 818.354.0137 F: 818.393.4445 Research emphases: Planetary geophysics and remote sensing; thermal environments and polar volatiles on the Moon and other airless bodies; Mars polar energy balance, seasonal cycles and climate; icy satellite surface composition, geological evolution, and habitability EDUCATION 2010 2005 2003 PhD MS BS Geophysics and Space Physics Geophysics Geophysics UCLA Stanford University Stanford University NASA Jet Propulsion Laboratory California Institute of Technology University of California, Los Angeles Staff Scientist Postdoctoral Scholar Graduate Student Researcher EMPLOYMENT 2012–present 2010–2012 2006–2010 MISSION EXPERIENCE NASA Lunar Reconnaissance Orbiter / Diviner Lunar Radiometer – Co-Investigator (2011 – present) Designed remote infrared observations of the LCROSS impact and modeled volatile behavior; characterized lunar regolith structure using Diviner observations of the Moon’s cooling during eclipse NASA Mars Reconnaissance Orbiter / Mars Climate Sounder – Science Team member (2007 – present) Led polar science investigation, including first infrared identification of polar carbon dioxide snow clouds and their role in regulating the present-day climate of Mars NASA/ESA Cassini-Huygens / VIMS – science team collaborator (2006 – present) NASA Galileo / NIMS – science team collaborator/data analysis (2009) ESA Mars Express / HRSC – data analysis (2006) SELECTED PUBLICATIONS Hayne, P. O., and O. Aharonson (2013), Topographically shadowed ice on Ceres, in prep. for JGR. Hayne, P. O., D. A. Paige, N. G. Heavens (2013), The role of snowfall in forming the seasonal ice caps of Mars : Models and constraints from the Mars Climate Sounder, submitted to Icarus. Hayne, P. O., T. B. McCord, and C. Sotin (2013), Titan’s surface composition : Correction for atmospheric effects derived from near-infrared solar occultation measurements by Cassini VIMS, submitted to Icarus. Barnes, J. W., B. J. Buratti, E. P. Turtle, J. Bow, P. A. Dalba, J. Perry, R. H. Brown, S. Rodriguez, S. Le Mouelic, K. H. Baines, C. Sotin, R. D. Lorenz, M. J. Malaska, T. B. McCord, R. N. Clark, R. Jaumann, P. Jet Propulsion Laboratory Paul O. Hayne 25 Composition of Titan’s Dunes O. Hayne, et al. (2013), Precipitation-Induced Surface Brightenings Seen on Titan by Cassini VIMS and ISS, Planetary Science, 2, p. 1. Hayne, P. O., D. A. Paige, J. T. Schofield, D. M. Kass, A. Kleinböhl, N. G. Heavens, and D. J. McCleese (2012), Carbon dioxide snow clouds on Mars: South polar winter observations by the Mars Climate Sounder, J. Geophys. Res., 117, E08014, doi:10.1029/2011JE004040. Vasavada, A. R., J. L. Bandfield, B. T. Greenhagen, P. O. Hayne, et al. (2012), Lunar Equatorial Surface Temperatures and Regolith Properties from the Diviner Lunar Radiometer Experiment, Journal of Geophysical Research 117, E00H18. Hayne, P. O., B. T. Greenhagen, M. C. Foote, M. A. Siegler, A. R. Vasavada, and D. A. Paige (2010), Diviner Lunar Radiometer Observations of the LCROSS Impact, Science, 330, 477. Paige, D. A., M. A. Siegler, J. A. Zhang, P. O. Hayne, et al. (2010), Diviner Observations of Cold Traps in the Lunar South Polar Region: Spatial Distribution and Temperature, Science 330, 479. Greenhagen, B. T., P. G. Lucey, M. B. Wyatt, T. D. Glotch, C. C. Allen, J. A. Arnold, J. L. Bandfield, N. E. Bowles, K. L. Hanna, P. O. Hayne, E. Song, I. R. Thomas, and D. A. Paige (2010) Global Silicate Mineralogy of the Moon from the Diviner Lunar Radiometer, Science 329, 1507. McCord, T. B., …, and P. O. Hayne (2010), Hydrated minerals on Europa's surface: An improved look from the Galileo NIMS investigation, Icarus 209, 639-650. Barnes, J. W., …, P. O. Hayne, et al. (2009), VIMS Spectral Mapping Observations of Titan during the Cassini Prime Mission, Planetary and Space Sciences, vol. 57, issue 14-15, pp. 1950-1962. McCord, T. B., P. Hayne, et al. (2008), Titan's surface: Search for spectral diversity and composition using the Cassini VIMS investigation, Icarus, vol. 194, pp. 212-242. BOOK CHAPTER: Aharonson, O., A. Hayes, P. O. Hayne, R. Lopes, A. Lucas, J. T. Perron, (2012), Titan's Surface Geology, in: C. G. Mueller-Wodarg, T. Cravens and E. Lellouch (Ed.), Titan: Surface, Atmosphere and Magnetosphere, Cambridge University Press, Cambridge, UK. RECENT CONFERENCE ABSTRACTS AND PRESENTATIONS: Hayne, P. O. and O. Aharonson (2012), Polar ice caps on Ceres: predictions for Dawn, Bulletin of the American Astronomical Society, 44. Hayne, P. O., et al. (2011), The Moon’s Extremely Insulating Near-Surface: Diviner Observations of a Total Lunar Eclipse, American Geophysical Union Fall Meeting 2011. Hayne, P. O., and D. A. Paige (2009), Clouds in the Polar Night of Mars: Modeling and Observations with the Mars Climate Sounder, paper presented at LPSC XL, p. 1849. Hayne, P. O., et al. (2009), Titan's Near Infrared Atmospheric Transmission and Surface Reflectance from the Cassini Visual and Infrared Mapping Spectrometer, paper presented at LPSC XL, p. 1863. HONORS 26 Keck Institute of Space Studies, Lead: “New Approaches to Lunar Ice Detection and Mapping” (2013) NASA Group Achievement Awards: Mars Climate Sounder Science Team (2010, 2011), Diviner Lunar Radiometer Science Team (2011) and Operations Team (2011) Best Student Paper, NASA Lunar Science Forum (2010) Simon Latimer Award for Service, Dept. of Earth & Space Sciences, UCLA (2008) NASA Astrobiology Institute Scholarship – Astrobiology Summer School, Spain (2008) Institute of Geophysics and Planetary Physics (IGPP) Graduate Fellowship (2006 – 2008) Chancellor’s Prize, UCLA – Awarded to top incoming graduate students (2006) Graduate Research and Teaching Assistantship, Stanford University (2003 – 2005) Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Physics Department Undergraduate Fellowship, Stanford University – Summer support (2001) Jet Propulsion Laboratory Paul O. Hayne 27 Composition of Titan’s Dunes Current Address 412 Space Science Bldg. Ithaca, NY 14853-6801 Alexander Gerard Hayes http://www.alexanderghayes.com hayes@astro.cornell.edu (607) 793-7531 EDUCATION Ph.D. Planetary Science M.Eng. Applied & Engineering Physics B.A. Astronomy / Physics, Summa Cum Laude B.A. Astrobiology, Summa Cum Laude SELECTED AWARDS Ronald Greeley Early Career Award (2012) Sigma Xi Young Scholar Procter Prize (2008) Permanent Address 219 Buttermilk Lane Ithaca, NY 14850 California Institute of Technology Cornell University Cornell University Cornell University April 2011 Dec. 2003 May 2003 May 2003 David Delano Clark Award [Best Thesis] (2004) NASA Group Achievement Awards (MER/Cassini) PROFESSIONAL POSITIONS - Assistant Professor; Cornell University, January 2013-Present Miller Research Fellow; University of California at Berkeley, July 2011-December 2012 Post-Doctoral Scholar / Graduate Student; Caltech, April 2011 – July 2011 / Sep. 2006 – March 2011 Consultant / Associate Staff; MIT Lincoln Laboratory, Sep. 2006 – Sep. 2007 / May 2004 – Sep. 2006 Remote Software Consultant; Arizona State University, May 2004 – Sep. 2006 MER Science Team Affiliate; Jet Propulsion Laboratory, Jan. 2004 – May 2004 SELECTED PUBLICATIONS [-] O. Aharonson, A. G. Hayes, R. M. C. Lopes, A. Lucas, P. Hayne, T. Perron, and L. A. Soderblom . Titan’s Surface Geology (2012), In: I. Mueller-Wodarg (Ed) Titan: Surface, Atmosphere, and Magnetosphere. 646pp., Cambridge Planetary Science Series, Cambridge University Press. [-] J. Grotzinger, A. G. Hayes, M. O. Lamb, S. M. McLennan. Sedimentary Processes on the Earth, Mars, Titan, and Venus (in-press), In: M. Bullock and M. Mackwell (Eds) Comparative Climatology of Terrestrial Planets. 600pp., Space Science Series, University of Arizona Press, Tucson. [-] A. G. Hayes, R. D. Lorenz, M. Manga, M. A. Donelan, H. L. Tolman, W. W. Fischer, S. D. Graves, M. P. Lamb, J. I. Lunine, P. Encrenaz, O. Aharonson, and the Cassini RADAR Team. Wind driven capillary-gravity waves on Titan’s Lakes: Hard to Detect or Non-Existent? Icarus 2013. [-] A. Le Gall, A. G. Hayes, and R. C. Ewing, M. A. Janssen,J. Radebaugh, C. Savage, and P. Encrenaz. Latitudinal and altitudinal controls of Titan’s dune field morphometry. Icarus, 2012. [-] E. P. Turtle, J. E. Perry, A. G Hayes, R. D. Lorenz, J. W. Barnes, A. S. McEwen, R. A. West, T. L. Ray, A. D. Del Genio, J. M. Barbara, and E. L. Schaller. Extensive and Rapid Surface changes near Titan’s equator: Evidence for April Showers? Science, 2011. [-] A. G. Hayes, O. Aharonson, J. Lunine, H. Zebker, L. Wye, R. Lorenz, E. Turtle, P. Paillou,G. Mitri, S. Wall, E R. Stofan, C. Elachi, and The Cassini RADAR Team. Transient Surface Liquid in Titan's Polar Regions from Cassini. Icarus, vol. 211, January 2011 [-] A. G. Hayes, J. Grotzinger, L. Edgar, W. Watters, S. Squyres, and J. Sohl-Dickstien. Reconstruction of Ancient Eolian Bed Forms and Paleo-Currents from Cross-Bedded Strata at Merdiani Planum, Mars. Journal of Geophysical Research: Planets, Vol. 116, E00F21, April 2011. [-] A. G. Hayes, A. S. Wolf, O. Aharonson, H. Zebker, R. Lorenz, P. Paillou, S. Wall, and C. Elachi. Bathymetry and Absorptivity of Titan's Ontario Lacus. JGR: Planets, Vol. 115, E09009, Sep. 2010. [-] O. Aharonson, A. G. Hayes, J.I. Lunine, R.D. Lorenz, M.D. Allison, and C. Elachi. An asymmetric distribution of lakes on Titan as a possible consequence of orbital forcing. Nature Geo., Nov. 2009. [-] A. G. Hayes, O. Aharonson, P. Callahan, C. Elachi, Y. Gim, R. Kirk, K. Lewis, R. Lopes, R. Lorenz, J. Lunine, K. Mitchell, G. Mitri, E. Stofan, and S. Wall. Hydrocarbon lakes on Titan: Distribution and interaction with a porous regolith. Geophysical Research Letters, 35:9204, May 2008. 28 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Jean-Philippe Combe The Bear Fight Institute Box 667, 22 Fiddler’s Road Winthrop WA 98862 email: jean-philippe_combe @ bearfightinstitute.com Professional Experience June 2006 – present Research Scientist at the Bear Fight Institute in Winthrop, WA Research activities: - Mineralogy, photometry and thermal emission of the Moon with Chandrayaan-1 Moon Mineralogy Mapper hyperspectral images, the Diviner Lunar Radiometer Experiment and Clementine UVVIS + NIR multispectral images - Preparation of future observations of asteroid 4-Vesta by the imaging spectrometer VIR on the Dawn spacecraft. - Mapping of mineralogical surface composition and geology of Mars with Mars Express OMEGA and HRSC, and Mars Reconnaissance Orbiter CRISM spectral data - Surface composition and atmospheric spectrophotometric properties of Titan with the Cassini VIMS imaging spectrometer - Identification of hydrated salts on Europa with the Galileo NIMS imaging spectrometer - Recent development of spectral unmixing algorithms and absorption band identification. - Surface composition and roughness of telluric planets and satellites of the solar system February – March 2006 Visiting Postdoctoral Fellow at the Bear Fight Center in Winthrop, WA October 2005 – June 2006 Post-doc and graduate assistant at University of Nantes, France October 2005 Visiting Ph.D. Student Fellow at the Space Science Institute in Winthrop, WA September 2001 – October 2005 Graduate assistant at University of Nantes, France Education and academic degrees October 2005 Graduated from the University of Nantes, France, with a Ph.D. in Planetary Sciences – Remote Sensing; thesis advisor Pr. Christophe Sotin Thesis title: Studies of planetary surfaces by hyperspectral visible-infrared remote sensing (in french: Etudes des surfaces planétaires par télédétection visible infrarouge hyperspectrale) June 2001 Graduated from the University of Toulouse, France, with a Master in Earth and Environmental Sciences; speciality: Dynamics of the Earth and Telluric Planets; advisors Pr. Claude d’Uston and Dr. Serge Chevrel Computer skills Platforms: UNIX, Linux, PC Packages: IDL, ENVI, Excel Jet Propulsion Laboratory Paul O. Hayne 29 Composition of Titan’s Dunes Thomas B. McCord Contacts: Bear Fight Institute Box 667, 22 Fiddler’s Road Winthrop WA 98862 509 996 3933 ph; 509 996 3772 fax+ email: mccordtb@bearfightcenter.com Ph.D. M.S. B.S. FORMAL EDUCATION Planetary Science and Astronomy (double degree), California Institute of Technology, Pasadena, CA, 1968 Geology, California Institute of Technology, Pasadena, CA, 1966 Physics, Pennsylvania State University, State College, PA, 1964 FIELDS OF ACTIVITY Research into Physics of surfaces of the Earth and Planets, and Science and application of remote sensing from the ground, air and space. Develop instrumentation and software for remote sensing research and applications, Plan and execute air and space missions and experiments, Process and analyze image, spectral and other databases. Education and training of graduate students and young scientists Advise private and public institutions. CURRENT POSITIONS Senior Research Scientist, Director, The Bear Fight Center (2002 – present) Professor emeritus University of Hawaii (2002 - present) Adjunct Professor, University of Washington (2002 – present) Distinguished Visiting Scientists, Jet Propulsion Laboratory (2002 – present) MAJOR PREVIOUS POSITIONS Visitor in Planetary Sciences, California Institute of Technology (2004-2008) Senior scientists, Space Sciences Institute (2004 – 2007). Senior scientists and Division Director, Planetary Science Institute (2002 - 2004). Distinguished Visiting Scientist, Inst. for Space Physics, CNR, Italy (March-May 2003; MarchApril, 2005) Distinguished Invited Professor, University of Nantes, France (March-June 2002). Professor Planetary Sciences (tenured), University of Hawaii (1979-2001). [Retired and elected emeritus professor] Chairman and Chief Scientist, SETS, Inc. (1980-1996). [Successfully sold company.] Asst. Director, Institute for Astronomy, University of Hawaii (1976-1979) (head, observatories development and operations and head engineering division). [Resigned to focus on research and education.] Professor, Earth and Planetary Sci. (tenured), Mass. Inst. of Technology (1968-1978). [Resigned tenured position to move to University of Hawaii and Mauna Kea Observatory. Maintained position in M.I.T. Center for Space Research until 1986.] Post Doctoral Research Fellow, California Institute of Technology (1967-1968). [Resigned to move to M.I.T.] Graduate Student, California Institute of Technology (1964-1967) [Graduated] Undergraduate Student, Pennsylvania State University (1991-1964) [Graduated] U.S. Air Force (1958-1961) [Honorably discharged] 30 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Current and Pending Support Principal Investigator: Paul O. Hayne Sponsoring Agency Title of award or project Program Name (if appropriate) or Institution CURRENT SUPPORT Proposed period of performance Budget Commitment in fractions of a full time Work Year Mars Climate Sounder Extended Mission 2 Mars Reconnaissance Orbiter NASA Michael Kelley (202) 358-0607 10/2012 3/2015 $30M/FY 0.48 Diviner Radiometer (JPL Tasks) Lunar Reconnaissance Orbiter NASA Robert Fogal (202) 358-2289 10/2012 3/2015 $4M/FY 0.48 New Approaches to Lunar Ice Detection and Mapping Keck Institute of Space Studies 2013 Study Program JPL Katherine Dumas (818) 354-6546 3/2013 2/2014 $50k/FY 0.04 The Virtual Planet Modeling Team SSERVI NASA Yvonne Pendleton (650) 604-1850 10/2013 10/2018 $6 Million 0.2 Applied Physics Lab SSERVI Team SSERVI NASA Yvonne Pendleton (650) 604-1850 10/2013 10/2018 $6 Million 0.2 Georgia Tech SSERVI Team SSERVI NASA Yvonne Pendleton (650) 604-1850 10/2013 10/2018 $6 Million 0.2 Effects of Small Scale Hypervelocity Impact Cratering on the Moon Lunar Advanced Science and Exploration Research (LASER) NASA Robert Fogal (202) 358-2289 10/2013 10/2016 $100k 0.08 Thermal Modeling for Lunar AtmosphereSurface Interactions Lunar Atmosphere and Dust Explorer (LADEE) Guest Investigator Program NASA Sarah Noble (202) 643-5862 8/2013 7/2015 $200k 0.2 NASA Henry Throop (202) 358-1364 8/2013 7/2015 $200k 0.2 PENDING SUPPORT Composition of Titan's Cassini Data Analysis and Dunes: Constraints from Participating Scientists (CDAPS) Cassini VIMS and RADAR NOTE: If the proposed investigation is funded, the PI will decrease his level of effort on the Lunar Reconnaissance Orbiter and Mars Reconnaissance Orbiter science teams in order to fully complete the tasks in this proposal. Other members of those teams are willing and able to increase their efforts by a commensurate amount, as deemed necessary by their respective PIs. Jet Propulsion Laboratory Paul O. Hayne 31 Composition of Titan’s Dunes Co-Investigator: Alexander G. Hayes Current Support: X Current Pending Submission Planned in Near Future Project/Proposal Title: Seas, Lakes, Channel Networks, and Hillslopes: a coupled analysis to explore the evolution of Titan’s Polar Landscapes [NNX13AG03G] Role of A. Hayes: Principal Investigator Source of Support: ROSES 2012, CASSINI DATA ANALYSIS AND PARTICIPATING SCIENTSIST PROGRAM Point of Contact: Chritina Richey (Planetary Science Div. Science Mission Directorate NASA) Ph. (202) 358-1364 E-mail: HQ-CDAP@mail.nasa.gov Award Amount: $537,045 ($300,000 to A. Hayes) Period Covered: 1/1/2013-12/31/2015 Person-Months Commitment to the Project: 2 MM Fraction of Work Year: 16% X Current Pending Submission Planned in Near Future Project/Proposal Title: Role of A. Hayes: Source of Support: Point of Contact: Cornell / NASA Spacecraft Planetary Imaging Facility (SPIF) [NNX13AC79G] Principal Investigator ROSES 2012, PLANETARY GEOLOGY AND GEOPHYSICS PROGRAM Michael S. Kelley (Planetary Science Div. Science Mission Directorate NASA) Ph. (202) 358-0607 E-mail: HQ-PGG@mail.nasa.gov Award Amount: $120,000 ($120,000 to A. Hayes) Period Covered: 1/1/2013-12/31/2013 Person-Months Commitment to the Project: 1 MM Fraction of Work Year: 8% Pending Support: Current Pending X Submission Planned in Near Future Microwave Observations of Saturn’s Rings From Cassini Principal Investigator ROSES 2013, CASSINI DATA ANALYSIS AND PARTICIPATING SCIENTSIST PROGRAM Point of Contact: Chritina Richey (Planetary Science Div. Science Mission Directorate NASA) Ph. (202) 358-1364 E-mail: HQ-CDAP@mail.nasa.gov Award Amount: $125,507 Period Covered: 1/1/2014-12/31/2014 Person-Months Commitment to the Project: 1 MM Fraction of Work Year: 8% Project/Proposal Title: Role of A. Hayes: Source of Support: Current Project/Proposal Title: Role of A. Hayes: Source of Support: Point of Contact: Award Amount: 32 Pending X Submission Planned in Near Future Investigation of Titan's geological structures and surface materials from coanalysis of Cassini ISS, VIMS, and RADAR data Co-Investigator (PI is Elizabeth Turtle, JHU/APL) ROSES 2013, CASSINI DATA ANALYSIS AND PARTICIPATING SCIENTSIST PROGRAM Chritina Richey (Planetary Science Div. Science Mission Directorate NASA) Ph. (202) 358-1364 E-mail: HQ-CDAP@mail.nasa.gov $TBD ($48,914 to A. Hayes) Period Covered: 1/1/2014-12/31/2016 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Person-Months Commitment to the Project: 0 MM Intern) Current Pending Fraction of Work Year: 0% (Support for UG Summer X Submission Planned in Near Future EXPLORING TITAN’S GEOLOGY IN THREE DIMENSIONS WITH DIGITAL TOPOGRAPHIC MODELS FROM CASSINI RADAR STEREO Role of A. Hayes: Co-Investigator (Principal Investigator is Randolph Kirk, USGS) Source of Support: ROSES 2013, CASSINI DATA ANALYSIS AND PARTICIPATING SCIENTSIST PROGRAM Point of Contact: Chritina Richey (Planetary Science Div. Science Mission Directorate NASA) Ph. (202) 358-1364 E-mail: HQ-CDAP@mail.nasa.gov Award Amount: $TBD ($33,184 to A. Hayes) Period Covered: 1/1/2014-12/31/2016 Person-Months Commitment to the Project: 0.25 MM Fraction of Work Year: 2% Project/Proposal Title: Current Pending X Submission Planned in Near Future Characterizing Titan's dunes and dune-topography interactions: Implications for climate change in Titan's equatorial region Role of A. Hayes: Co-Investigator (Principal Investigator is Ryan Ewing, Texas A&M) Source of Support: ROSES 2013, CASSINI DATA ANALYSIS AND PARTICIPATING SCIENTSIST PROGRAM Point of Contact: Chritina Richey (Planetary Science Div. Science Mission Directorate NASA) Ph. (202) 358-1364 E-mail: HQ-CDAP@mail.nasa.gov Award Amount: $TBD ($105, 697 to A. Hayes) Period Covered: 1/1/2014-12/31/2016 Person-Months Commitment to the Project: 1 MM Fraction of Work Year: 8% Project/Proposal Title: Jet Propulsion Laboratory Paul O. Hayne 33 Composition of Titan’s Dunes Co-Investigator: Jean-Philippe Combe 34 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Co-Investigator: Thomas McCord Jet Propulsion Laboratory Paul O. Hayne 35 Composition of Titan’s Dunes Budget Justification Budget Justification: Narrative Summary of Personnel and Work Efforts Name Dr. Paul Hayne Dr. Jean-Philippe Combe Dr. Thomas McCord Dr. Alexander Hayes Organization JPL Bear Fight Institute Bear Fight Institute Cornell U. Role PI Co-I Co-I Work Commitment Fraction of Work Year (1840 hours) Year 1 Year 2 .21 .21 .05 .08 .02 .02 Co-I Facilities and Equipment Standard computer equipment and data processing software (including existing ENVI licenses) are available at no additional cost. The undergraduate student will use SOCET SET® and ArcGIS to map dunes, using software and workstations already available in Co-I Hayes’ lab at Cornell. Rationale and Basis of Estimate The cost proposal was prepared using JPL’s Pricing System and the current internally published Cost Estimation Rates and Factors, dated April, 2013. The derivation of the cost estimate is a grassroots methodology based on the expert judgment from a team of experienced individuals who have performed similar work. The team provides the necessary relevant experience to develop a credible and realistic cost estimate. The cognizant individuals identify and define the products and the schedule needed to complete the tasks for each work element. Then they generate the resource estimates for labor, procurements, travel, and other direct costs for each work element. The resource estimates are aggregated and priced using JPL’s Pricing System. JPL’s process assures that lower level estimates are developed and reviewed by the performing organizations and their management who will be accountable for successfully completing the proposed work scope within their estimated cost. 36 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Budget Justification: Details Year 1: Direct Labor: Dr. Paul Hayne is the PI and will oversee all aspects of the proposed work. Dr. Hayne will perform … ($X requested salary with $Y fringe benefits) Equipment: There are no major equipment purchases necessary Travel: The PI will travel to the LPSC meeting in The Woodlands, TX, to present the results of this investigation. Other: Multiple Program Support (MPS): $XX Facilities and Administrative Costs: Allocated Direct Costs (ADC): $XX General and Admin: $XX Subcontracts/Subawards: Desktop Network Chargebacks (calculated at $6.06/hr.): All JPL computers are subject to a monthly service charge that includes hardware, software, and technical support. ($XX) Total Estimated Cost for Year 1: $XX Year 2: Direct Labor: Dr. Paul Hayne is the PI and will oversee all aspects of the proposed work. In Year 2, Dr. Hayne will focus on … ($XX requested salary with $XX fringe benefits) Equipment: There are no major equipment purchases necessary Travel: The PI will travel to … Other: Multiple Program Support (MPS): $XX Facilities and Administrative Costs: Allocated Direct Costs (ADC): $XX General and Admin: $XX Subcontracts/Subawards: Jet Propulsion Laboratory Paul O. Hayne 37 Composition of Titan’s Dunes Desktop Network Chargebacks (calculated at $6.06/hr.): All JPL computers are subject to a monthly service charge that includes hardware, software, and technical support. ($XX) Total Estimated Cost for Year 2: $XX 38 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Budget Details Jet Propulsion Laboratory Paul O. Hayne 39 Composition of Titan’s Dunes Budget Justification: Participating Scientist Request Narrative Summary of Personnel and Work Efforts Facilities and Equipment Rationale and Basis of Estimate Details Year 1 Year 2 40 Paul O. Hayne Jet Propulsion Laboratory Composition of Titan’s Dunes Budget Details: Participating Scientist Request Jet Propulsion Laboratory Paul O. Hayne 41