Near Earth Asteroid Detection System Technology Validation Mission Design Review AERO 426 – Space Systems Design Advisor Dr. Hyland Project Manager Assistant Project Manager Jesus Orozco Jeff Campbell 1 Table of Contents Overview…………………………………………………………………………………………………….. 3 Background Information………………………………………………………………………………….... 4 Mission Statement………………………………………………………………………………………….. 8 Requirements……………………………………………………………………………………………….. 9 Design Results……………………………………………………………………………………………… 11 Mission Overview……………………………………………………………………………………………14 Observation Candidates…………………………………………………………………………………....15 Light Gathering Optics……………………………………………………………………………………... 22 Formation………………………………………………………………………………………………….....30 GNC & Communication…………………………………………………………………………………..... 39 Propulsion…………………………………………………………………………………………………… 48 Power & Thermal…………………………………………………………………………………………… 52 Structures………………………………………………………………………………………………….... 60 Mass Estimate…………………………………………………………………………………………….... 69 Budget & Schedule………………………………………………………………………………………….70 Conclusions……………………………………………………………………………………………….....73 Appendix I: References…………………………………………………………………………………..... 75 Appendix II: Asteroid Occultations………………………………………………………………………... 78 2 Overview • • • • • • • • • • • • • • Background Information Mission Statement Introduction Requirements Mission Overview Observation Candidates & Performance Evaluation Group Light Gathering Optics Design Group Formation Design Group GNC & Communications Group Propulsion Group Power & Thermal Group Structures Group Budget & Schedule Conclusions 3 Background Information • Many objects hit Earth all the time • Sometimes these objects are large enough we can notice them and they can cause damages – Chelyanbinsk February 15, 2013 4 Conventional Method of Observing Basic technique: A set of observers note the time and duration that a star disappears from sight. Then plot the ground track of the asteroid during the occultations and get the asteroid shape (silhouette) This seems very straightforward, so what’s left to learn? Answer: The simple technique assumes the asteroid is big enough (10s to 100s of km) to cast a sharp shadow. “Small” asteroids (like Apophis) may create “interference patterns”, not well defined shadows! 5 5 NEA Detection Summary Diameter(m) >1000 1000-140 140-40 40-1 Distance (km) for which F>100 (=0.5 m) >20 million < 20 million, > 400,000 <400,000 (Lunar orbit) >32,000 (GEO orbit) <32,000 >20 H (mag) 17.75 17.75-22.0 22.0-24.75 >24.75 N estimated 966 `14,000 ~285,000 ?? N observed 899 4,557 2,259 1,685 O/E 93% ~33% ~1% ?? Only 1% detected, and if you wait for sharp shadows, it’s probably too late 6 Stellar Occultation System Array of light collecting apertures, each equipped with a photo detector Distant star Shadow pattern Resolved silhouette I k k 1,..., N Measurements of intensities relative to ambient intensity U k xk Phase Retrieval algorithm 2 U x Huygens Fresnel Inversion 7 Mission Statement The mission objective is to validate advanced stellar occultation technology capable of detecting small, potentially hazardous Near Earth Asteroids. 8 Top-Level Requirements • Address the complete system, including the CubeSats, their formation, data links, ground system, etc. • Each CubeSat must host a 10cm diameter telescope and light intensity detector. • Assume visible light with wavelength centered at 0.5 µm • Plan for a minimum of 12 and a maximum of 96 CubeSats. • Ground station in CS 9 Top-Level Requirements • Deploy the CubeSats in LEO with orbit lifetime no greater than 18 months • CubeSat array must be capable of recording the shadow pattern of a 40m asteroid at 1 AU distance • Intensity detectors should be capable of recording light from a 12th magnitude star with Signal-to-Noise Ratio (SNR) of at least 10. (~80 observations possible). • Obtain silhouette of asteroids in the 40 to 140m range with at least 10 pixels across. • Cost < $15M 10 Design Results • • • • • Two satellite designs: Optic and Master 15 Optic Satellites, 1 Master Y-formation in Low Earth Orbit at 450km Independent Pegasus Launch Deployable Cassegrain Optic with photodiode 11 Optic Satellite Master Satellite 12 13 Mission Overview • • • • • Planning & Development Production Initial Launch Normal Mission Operations End-of-life Disposal 14 Observation Candidates Technical Group Lead John Maksimik Team Members Ramon Calzada Kimberly Ellsworth Jordan Heard Kristin Nichols Jesus Orozco 15 Observation Candidates • Technology: occultation of asteroid within 40 -140 m diameter • Technology Validation: Most known occultations involve large asteroids – Although the technology will be validated on larger asteroids, the array is sized for 40 – 140 m • Instead of occulting a large asteroid, we will occult the first ripple coming off of the shadow of the asteroid – Use the shadow data to determine the distance to the asteroid and the diameter of the asteroid – Adequate SNR is necessary to observe the shadow ripples 16 Shadow Ripple • The length of the first ripple is proportional to 𝑧𝜆 where 𝑧 is the distance to the asteroid and 𝜆 is the wavelength. • The intensity height of the first ripple is used to find the size of the asteroid. • Occultations by the Moon are also possible. Intensity Length 17 Signal to Noise Ratio • Constant array width of 3.75km • Dark count of 365kHz total *Diameter- circular distance around array 18 List of Asteroids Asteroid Date Diameter Ripple Length Star Magnitude 241 Germania 22 Jan 2014 184 km 427 m 9.4 7 Iris 27 Jan 2014 253 km 432 m 8.7 194 Prokne 4 Feb 2014 167 km 434 m 9.2 51 Nemausa 23 Mar 2014 166 km 397 m 9.7 172 Baucis 24 Mar 2014 67 km 435 m 6.7 51 Nemausa 28 Mar 2014 166 km 404 m 7.7 776 Berbericia 21 Apr 2014 150 km 504 m 10.1 105 Artemis 3 May 2014 116 km 410 m 7.7 34 Circe 4 May 2014 117 km 383 m 7.4 206 Hersilia 7 May 2014 94 km 409 m 7.5 19 List of Asteroids Asteroid Date Diameter Ripple Length Star Magnitude 451 Patientia 12 May 2014 235 km 445 m 8.5 13 Egeria 1 Jun 2014 215 km 374 m 9.6 103 Hera 30 Jun 2014 83 km 358 m 6.1 386 Siegena 2 Aug 2014 208 km 409 m 9.8 409 Aspasia 21 Aug 2014 183 km 365 m 10.4 81 Terpsichore 4 Oct 2014 134 km 389 m 11.0 270 Anahita 7 Oct 2014 47 km 279 m 9.9 238 Hypatia 24 Nov 2014 169 km 401 m 11.0 7 Iris 28 Nov 2014 253 km 431 m 10.1 3 Juno 28 Nov 2014 290 km 346 m 9.0 702 Alauda 18 Dec 2014 219 km 425 m 6.2 20 241 Germania Ripple length: 427 m Date: 22 Jan 2014 Caribbean, Mexico Star: TYC 1354-00434-1 mag 9.4 Diameter: 184 km 21 Light Gathering Optics Technical Group Lead Chris McCrory Team Members Emily Boster Jeffrey Campbell Daniel Charles Joseph Duggan Vianni Ricano 22 Solid works model 23 Zemacs Optical Design • Boom Length • Secondary diameter • Primary Mirror Diameter • Radii of curvature of primary and secondary mirrors • Focal Length • Spot Diagram • Distance between primary and focal plane 24 Cassegrain Telescope Mirror Type Diameter Radius of Curvature Primary Mirror 7.0 cm -64.7421 cm Secondary Mirror .52 cm -5.0125 cm Distance Between Mirrors: 30.0 cm Distance Between Primary and Photodiode: 3.0 cm Focal Length: 6.0 m 11/26/2013 25 Spot Diagrams Radius 235.7 μm 26 SensL MiniSM Silicon Photomultiplier 30035 series • Avalanche Photodiode set in Geiger mode Spectral Range 400-1000 nm Peak Wavelength 500 nm Bandwidth 20 MHz Dark Count Rate 365 kHz Dark Current 100 nA Active Area 3X3 mm2 Operating Temperature Range 0 C - +30 C Power Requirements +5V Price per Unit $ 700 Total Price (15 optic sats) $ 10,500 27 Photomultiplier Weight 70 g Dimensions (H X W X L) 45 X 35 X40 mm3 • Built in Peltier thermoelectric cooling system • Coaxial Cable 28 Formation Design Group Technical Group Lead Joshua Kinsey Team Members Hope Russell Candace Hernandez Jose Long Brian Musslewhite Brigid Flood 29 Formation 10 pixels 120 ° 120 ° 120 ° 10 pixels 30 Euler Hill Reference Frame 31 Euler Hill Approximation Non-dimensionalized equations of motion for the perturbing force in the local Hill frame: 2 d 2u dv 1 P 2 3u Fx 2 df df rc m 2 2 d 2v du 1 P 2 Fy 2 df df rc m 2 2 d 2w 1 P w Fz 2 df rc m 2 Solution for Force Free Motion and Impulse Conditions: sin f u f 4 3cos f cos f u f 3sin f v f 6 f sin f 2 1 cos f v f 6 1 cos f 2sin f w f 0 0 w f 0 0 where f f f 0 , and f 0 f t 0 . 0 2 1 cos f 0 2sin f 0 0 1 4 sin f 3 f 0 0 4 cos f 3 0 0 0 cos f 0 0 sin f 0 u f0 0 u f 0 0 v f0 v f0 0 w f0 sin f cos f w f 0 32 Euler Hill Approximation u f 4 u f 0 2v f 0 (3u f 0 2v f 0 )cos f u f 0 sin f u f u f 0 cos f 3u f 0 2v f 0 sin f v f 2u f 0 v f 0 6u f 0 3v f 0 f 2u f 0 cos f 6u f 0 4v f 0 sin f v f 6u f 0 3v f 0 6u f 0 4v f 0 cos f 2u f 0 sin f w f w f 0 cos f w f 0 sin f w f w f 0 cos f w f 0 sin f 33 Formation Deployment 120° 120° 120° 34 Cube Sate Delta-V Calculation Deployment ΔV vs. Asteroid Radius 80 Asteroid radius, a (m) 70 60 50 40 30 20 Delta-V, Inner Circle 10 Delta-V, Outer Circle 0 0 1 2 3 4 5 6 7 8 9 ΔV (m/s) Thruster Specs • Propellant volume = 95 cm3 • Propellant density = 0.556 g/cm3 • Isp = 65 sec • Maximum Mass (full Cube Sat) = 4 kg Δvmax = 8.411 m/s 35 Station Keeping • Perturbations for LEO orbits – Atmospheric Drag – J2 Effect • Only J2 Effect considered for station keeping calculations • Orbit eccentricity determined by Maximum Radial Component of Formation Width divided by Nominal Orbit Radius • Delta-Vs for 1 year is 0.0496km/s • Δm/m = .00036% 36 Deployment Vehicle Delta-V Calculation • Assumed a simple two body rendezvous problem and a designed elliptical orbit a b • Calculated using conservation of energy: 𝑣 2 𝜇 2𝜇 − = 2 𝑟 𝑎 • Delta-V values ranged from 350.332 m/s to 350.362 m/s GNC & Communications Techincal Group Lead Josh Jennings Team Members Chris Cederberg Ken Cundiff Nicholas Gawloski Kristina Loftin Michael Young 38 GNC – Control Package • Blue Canyon XACT – Complete GNC Package • • • • • • • Reaction Wheels Torque Rods Sun Sensors Star Tracker IMU Magnetometer GPS – Pointing Accuracy: 0.007 ° – $110,000 (with GPS) – Whole system not flight tested, just the star tracker Blue Canyon XACT 39 GNC – Control Package • Issues – Very expensive; propagated over many craft – Need extremely high pointing accuracy • Conclusions – XACT meets minimum specifications – Will use XACT for GNC 40 GNC – Dynamics Control Verification • Control Response from Simulink – PID Control using Reaction Wheels in XACT – Rotated to some arbitrary angles • Shows ability of XACT Reaction Wheels to change orientation of 3U cubesat • Does not factor in environmental disturbances 41 Telecommunications • Downlink: Mother Sat to Earth – S-Band Transmitter w/ patch antenna • • • • • Gain: 8 dBi Beamwidth: 60° 2.4 - 2.483 GHz 1 Mbps Link Margin: 6.1 dB Power Transmitting Power System Losses Antana Gain EIRP (Effective Isotropic Radiaded Power) Frequency (S-Band) Free Space Loss (max distance 1944 km) Atm/Prec Losses System Noise Temperature Total Propagation Loss Receive Antenna Gain System losses Eb/No Minumum for 10e-5 BER Margin 2W 2 dB 8 dB 9 dB 2.44 GHz 166 dB 1 dB 26 dbk 193 dB 31.5 dB 2 dB 14.1 dB 9.6 dB 4.5 42 dB Telecommunications • Uplink: Earth to Mother Sat – ISIS VHF downlink / UHF uplink Full Duplex Transceiver • Frequency – UHF: 400-450 MHz » 9600 bps – Deployable UHF/VHF antenna • UHF Gain: -6 dBi 43 Link Budget Uplink Transmitting Power 5W System Losses Antana Gain EIRP (Effective Isotropic Radiaded Power) 3 dB 16.4 dB 20.4 dB Frequency (S-Band) Data Rate Free Space Loss (max distance 1944 km) Atm/Prec Losses System Noise Temperature Total Propagation Loss 425 MHz 9600 kbps 166 dB 1 dB 26 dbk 193 dB Receive Antenna Gain System losses Eb/No Minumum for 10e-5 BER Margin -6 dB 2 dB 24.3 dB 9.6 dB 14.7 dB 44 Telecommunication • Crosslink: Eye Sat to Mother Sat – ISIS UHF downlink / VHF uplink Full Duplex Transceiver • Frequency – UHF: 400-450 MHz » 9600 bps – VFH: 130-160 MHz » 1200 bps – Deployable UHF/VHF antenna • UHF Gain: -6 dBi • VHF Gain: -5 dBi 45 Link Budget Cross Link UHF/VHF Crosslink UHF Transmitting Power System Losses Antana Gain EIRP (Effective Isotropic Radiaded Power) Frequency (UHF) Data Rate Free Space Loss (max distance 5 km) Atm/Prec Losses System Noise Temperature Total Propagation Loss Receive Antenna Gain System losses Eb/No Minumum for 10e-5 BER Margin 500 mW 3 dB -6 dB -12 dB 425 MHz 9600 kbps 98 dB 0 dB 26 dbk 124 dB -6 dB 2 dB 43.8 dB 9.6 dB 34.2 dB Crosslink VHF Transmitting Power System Losses Antana Gain EIRP (Effective Isotropic Radiaded Power) Frequency (VHF) Data Rate Free Space Loss (max distance 5 km) Atm/Prec Losses System Noise Temperature Total Propagation Loss Receive Antenna Gain System losses Eb/No Minumum for 10e-5 BER Margin 500 mW 3 dB -5 dB -11 dB 425 MHz 9600 kbps 98 dB 0 dB 26 dbk 124 dB -5 dB 2 dB 52.8 dB 9.6 dB 43.2 dB 46 Propulsion Technical Group Lead Evan Siracki Team Members Fernando Aguilera John Albers Randall Reams Nicholas Matcek James Kim 47 Launch Vehicle Pegasus XL • • • • 443 kg payload into LEO Launch cost - $11 million Diameter - 1.27 m 88% success rate – 100% success rate since 1996. • Allows for direct insertion into orbit 48 CubeSat Propulsion • Most of the cubesats currently in orbit do not have an active propulsion system. However, in order to keep our cubesats in formation small amounts of thrust are required to compensate for translational perturbations. This is necessary to allow for formation flying. 49 VACCO Micro-Thruster • VACCO/JPL Butane Micro-Thruster – Cold gas thruster – 5 multi-directional thrusters, ideal for translational perturbation corrections – Low power consumption: 100mW-4W peak – Low mass: 509g (50 g of propellant) – Low Isp: 70s – Vacuum tested but not flight tested 50 Power & Thermal Technical Group Lead Haylie Peterson Team Members Jeff Ham Jonathan Lagrone Lisa Malone Evan Marcotte Michael Wilkinson 51 Power Estimate Technical Teams Power Required (Optic) Power Required (Communication) Propulsion 2 watts 2 watts GNC 2 watts 2 watts Telecommunications 2 watts 7 watts Optics 2.5 watts 2.5 watts Optic Boom 15 watts 0 watts CPU 0.3 watts 0.3 watts Total Power 24.3 watts 14.3 watts • All calculations based on peak power required 52 BP4 Battery Pack • Easily fits in CubeSat • Provides enough power for internal components • Battery is rated for 30 W maximum. 53 P31US Power Module • 6 User-controlled output controls • Photovoltaic power conversion up to 30 W • Can accommodate panels with up to 7 solar cells in a string 54 CPU-NanoMind A712D • ARM7 processor - 8-40 Mhz • RTC - real time clock w/backup power keeps time 30-60 minutes without external power • MicroSD socket for up to 2GB storage • On-board magnetometer • 6x sun-sensor inputs 55 P110 Series GaAs Solar Panels • $2800/panel • Gallium Arsenide • Tends to have less noise than silicon (especially at high frequencies) • Emit light efficiently • Highly resistive (due to wide bandgap) • High-cost, high-efficiency • Specifications per panel • 30% efficiency • Up to 2.4 Watts absorption per orbit • Operational temperature: -40 C to +85 C • Compatibility: GomSpace NanoPower P31US power supply 56 THERMAL PROTECTION MULTI-LAYER INSULATION Max Thickness = 1mm • For thermal protection of the internal components of the CubeSat, we chose Multi-Layer Insulation with Kapton film for the outer layer and multiple layers of, a Dacron web, a Mylar film, and Deposited Aluminum in series for 2-35 layers. • With the thermal protection the maximum temperature inside the CubeSat is 355.9 K and minimum temperature 273.3 K, assuming the heat given off by internal components is 15 W. 57 Risk Assessment 1. Solar panels could get hit by space debris and/or possibly fail i. Moderate-low (0.4) ii. To mitigate this there is some redundancy because there are several solar panels on the cubeSat. Therefore, if one or two soalr panels fail enough power can still be provided to the cubeSat 2. Tear in the MLI could cause internal temperatures to be higher or lower than expected i. Low-High (0.3) ii. Using a thicker MLI would help prevent this if debris were to get through the solar panels 3. If power module fails then the battery pack could become overcharged, cause the batteries to heat up, and lower the battery life. i. Low-High (0.3) ii. Some power controls could be done by the CPU in case of an emergency failure of the power module. 58 Structures Group Technical Group Lead Tanner Black Team Members Veronica Betts Paden Coats David Kostecka Patrick Whalen Taylor Yeary 59 Major Structural Decisions Optics Satellite Optics Satellite Material 6000 series Aluminum Weight <300 grams Dimensions 10 cm x 10 cm x 340 cm (per CubeSat-Reqs.pdf) Telescope Support Material Graphite Epoxy Shell Total Weight <240 grams Units 3 Collapsed Dimensions 88 mm x 88 mm x 69 mm Extended Dimensions 88 mm x 88 mm x 203 mm 60 Major Structural Decisions Master Master Satellite Material 6000 series Aluminum Weight <200 grams Dimensions 10 cm x 10 cm x 200 cm (per CubeSat-Reqs.pdf) 61 Optics Satellite Collapsed/Exploded 62 Optics Satellite Breakdown Breakdown 1 11 10 9 8 2 7 6 5 4 3 1 Telescope Assembly 2 Satellite Structure 3 Thruster 4 GNC Components (Satellite as well) 5 Battery Pack 6 Transceiver 7 CPU 8 Optics Sensor 9 Large Optics Mirror 10 Telescope Motor 11 Threaded Rod for Motor 63 Master Satellite Shown without wall structure for easier viewing 64 Master Satellite Breakdown Breakdown 1 1 Thruster 2 Telecommunication Units 3 Telecommunication Units 4 Telecommunication Units 4 5 Battery Pack 5 6 GNC Components 7 Satellite 2 3 6 7 65 Risk • Telescope Motor Redundancy – Risk: Medium – High (0.5) – Mitigation: Multiple motors in case of failure • Structural Failure of Telescope – Risk: Low – Medium (0.2) – Mitigation: Redundancy in Telescope satellites • Component Placement – Risk: Medium – Medium (0.3) – Mitigation: Look into using bulkheads/dry bays to separate contrasting components 66 Further Considerations • • • • Loading Profiles Structural Frequency Analysis Detailed attachment design Fabrication and Assembly Instructions 67 Satellite Masses Optics Satellite Master Satellite System Mass (grams) System Mass (grams) Light Gathering/Optics 162 Structures 300 Structures 606.22 Propulsion 509 Propulsion 509 Power and Thermal 437 Power and Thermal 437 GNC/Communications 885 GNC/Communications 1015 Total 2,599.22 Total 2,261 68 Estimated Costs Component Type Cost (Optic/ Master) CubeSat Frame $7,500/$7500 Telecommunications $17,776/$40,355 Control Package $110,000/$110,000 Solar Panels $38,663/$27,617 Power System $9,383/$9,383 CPU $6,554/$24,000 Optics $10000/$0 Propulsion $17,250/$17,250 69 Estimated Costs Specific Costs Cost per T/N Satellite $217,126 Cost per Optic Satellite $236,105 Launch/Manufacturing Costs $74,400/Satellite Total Cost for the16 Satellites $4,949,101 Launch Costs $11,000,000 *These estimates are based on cubesat component costs from various component vendors and manufacturers. 70 Mission Schedule Element Typically Driven By Date Planning & Development Funding constraints System need date Two years after start Production Funding constraints Technology development System need date Three-Four years after start Initial Launch Launch availability System need date Five years after start Normal Mission Operations Planned operational life Satellite lifetime (18 months) Six years after start End-of-Life Disposal Burn back to atmosphere Seven years after start 1st Half Start 1/1/14 Planning & Development 1/1/14 - 12/31/15 1st Half 1st Half Production 1/1/16 - 6/1/17 1st Half 1st Half 1st Half Initial Launch 1/1/18 6/29/18 1st Half Finish End-of-Life 1/1/20 Disposal 7/1/19 1/1/20 Normal Mission Operations 1/1/18 - 12/31/19 71 Design Conclusions • Mission Design: 15 Optic Satellites and 1 Master • Optic satellite gathers occultation data, the master satellite communicates data to Earth. • Deployable Cassegrain Optics with photodiode • Y-formation in Low Earth Orbit at 450km • Independent Pegasus Launch • Total Satellite Costs: $4,949,101 for 16 satellites • Launch Costs: $11,000,000 72 Technology Validation • NEA Occultation- Validate the use of stellar occultation to characterize Near Earth Asteroids • Formation Flying of CubesatsDemonstrate the dynamics and feasibility of the use of multiple cubesats working together in formation in pursuit of a single goal 73 Questions? 74 Appendix I 75 References [1] [2] [3] J. R. Wertz and W. J. Larson, Space Mission Analysis And Design, Hawthorn: Microcosm Press, 2010. "2014 Best Asteroid Occultation Events," 27 May 2013. [Online]. Available: http://www.asteroidoccultation.com/2014-Best-Events.htm. [Accessed November 2013]. [4] Wikipedia, "Pegasus (rocket)," [Online]. Available: http://en.wikipedia.org/wiki/Pegasus_(rocket). J. Mueller, H. Richard and J. Ziemer, "SURVEY OF PROPULSION TECHNOLOGIES APPLICABLE TO CUBESATS," [Online]. Available: http://trsnew.jpl.nasa.gov/dspace/bitstream/2014/41627/1/10-1646.pdf. [5] V. Industries, "A Micro-Propulsion Systems for CubeSats". Patent 6,334,301, 27 April 2006. [6] "HJOL.COM," Harold Johnson Optical Laboratories, [Online]. Available: http://www.hjol.com/. [Accessed 29 November 2013]. 76 Component Selection Blue Canyon XACT (GNC Package) http://bluecanyontech.com/wp-content/uploads/2012/07/BCT-XACT-datasheet-1.5.pdf Deployable Antenna http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=66&cat egory_id=6&option=com_virtuemart&Itemid=70 ISIS UHF downlink / VHF uplink Full Duplex Transceiver http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=11&cat egory_id=5&option=com_virtuemart&Itemid=67 ISIS VHF downlink / UHF uplink Full Duplex Transceiver http://www.cubesatshop.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=73&cat egory_id=5&option=com_virtuemart&Itemid=67 CubeSat S-Band Transmitter http://www.clyde-space.com/cubesat_shop/communication_systems/301_cubesat-s-band-transmitter S-Band Patch Antenna http://www.clyde-space.com/cubesat_shop/communication_systems/302_s-band-patch-antenna Components http://gomspace.com/index.php?p=products MLI http://www.dunmore.com/products/multi-layer-films.html 77 Appendix II 78 7 Iris Ripple length: 432 m Date: 27 Jan 2014 N Brazil Star: TYC 0590-01325-1 mag 8.7 79 Diameter: 253 km 194 Prokne Ripple length: 434 m Date: 4 Feb 2014 Brazil, Colombia Star: TYC 0252-01354-1 mag 9.2 Diameter: 167 km 80 51 Nemausa Ripple length: 397m Date: 23 Mar 2014 Caribbean, Mexico Star: HIP 31495 mag 9.7 Diameter: 166 km 81 172 Baucis Ripple length: 435m Date: 24 Mar 2014 Star: HIP 96111 mag 6.7 Diameter: 67 km 82 51 Nemausa Ripple length: 404 m Date: 28 Mar 2014 Star: HIP 32049 mag 7.7 Diameter: 166 km 83 776 Berbericia Ripple length: 504m Date: 21 Apr 2014 SE USA Star: TYC 2426-01323-1 mag 10.1 Diameter: 150 km 84 105 Artemis Ripple length: 410m Date: 3 May 2014 NW Brazil, Peru Star: HIP 106110 mag 7.7 Diameter: 116 km 85 34 Circe Ripple length: 383 m Date: 4 May 2014 Peru, Ecuador Star: HIP 84647 mag 7.4 Diameter: 117 km 86 206 Hersilia Ripple length: 409 m Date: 7 May 2014 N Australia, Indonesia Star: HIP 88855 mag 7.5 Diameter: 94 km 87 451 Patientia Ripple length: 445 m Date: 12 May 2014 Japan, China, India Star: HIP 64387 mag 8.5 Diameter: 235 km 88 13 Egeria Ripple length: 374 m Date: 1 Jun 2014 New Guinea, N Australia Star: TYC 7353-02144-1 mag 9. Diameter: 215 km 89 103 Hera Ripple length: 358 m Date: 30 Jun 2014 Africa, Brazil, Bolivia, Chile Star: HIP 91781 mag 6.1 Diameter: 83 km 90 386 Siegena Ripple length: 409 m Date: 2 Aug 2014 Taiwan, SE Asia Star: TYC 0433-00335-1 mag 9. Diameter: 208 km 91 409 Aspasia Ripple length: 365 m Date: 21 Aug 2014 Taiwan, SE Asia, India Star: TYC 1137-00851-1 mag 10 Diameter: 183 km 92 81 Terpsichore Ripple length: 389 m Date: 4 Oct 2014 W USA, Hawaii Star: TYC 2410-01358-1 mag 11 Diameter: 134 km 93 270 Anahita Ripple length: 279 m Date: 7 Oct 2014 Russia, Middle East, Africa Star: HIP 113909 mag 9.9 Diameter: 47 km 94 238 Hypatia Ripple length: 401 m Date: 24 NOV 2014 Japan, China, SE Asia, South Af Star: TYC 0157-01065-1 mag 11 95 Diameter: 169 km 7 Iris Ripple length: 431 m Date: 28 NOV 2014 Brazil, Colombia, Ecuador Star: HIP 53745 mag 10.1 Diameter: 253 km 96 3 Juno Ripple length: 346 m Date: 28 NOV 2014 SE Asia, India, Middle East Star: HIP 43790 mag 9.0 Diameter: 290 km 97 702 Alauda Ripple length: 425 m Date: 18 DEC 2014 East Australia Star: HIP 13832 mag 6.2 Diameter: 219 km 98