Writing an Observing Proposal
PHY517 / AST443
Mid-term Course Assessment
• Ended Mar 29, 2013
• Suggestions:
– emphasize having to start labs ASAP
– more emphasis on the coding in the lab
descriptions
– changing groups between experiments
– hold data reduction classes sooner after the
beginning of the semester
• some groups had data in hand for about a week before
IDL sessions
Current Status of New Experiments
• Supernovae Ia
– obtain images in three bands (BVI) on at least 5 different
nights
– calibrate the photometry with respect to 10–15 stars with
known BVI apparent magnitudes
– fit light curve templates for the three bands, using publicly
available SN Ia fitting software
– determine absolute magnitude of SN and hence distance to
host galaxy
– compare to existing distance estimate to the galaxy found
from the literature
• Follow transit planet lab description for image
reduction and photometry calibration
Current Status of New Experiments
•
Gaseous nebulae
– obtain 3500–7500 Å spectra at several different distances from the
center
– obtain images of the slit locations for estimating angular separation
from center
– calibrate spectrograph with spectra of an A star interspersed
among your nebular spectra
– extract spectra with ATV
– wavelength calibrate spectra with respect to Balmer series in the A
star
– identify spectral lines and measure their fluxes
– options for analysis:
• determine size of He+ ionized region, if any from strength of He II line
• determine temperature and electron density from [N II], [O III] lines
• determine extinction law from ratio of Ballmer lines
Telescope Facilities
•
Space telescopes: annual proposals
– Hubble, Spitzer, Herschel, SOFIA, Chandra, etc
– heaviest oversubscription: 4 – 8 x
– approved programs are funded by NASA
•
National O/IR telescopes: semi-annual proposals
– NOAO (multiple 0.9 – 4 m telescopes, north + south), Gemini (8.2 m
north + south), IRTF (3.0 m)
– A and B observing semesters; Mar/Apr, Sep/Oct deadlines
– oversubscription: 1 – 5 x
– some travel funding only
•
National radio telescopes: proposals 2 or 3 times / year
– VLA, ALMA (interferometers), Arecibo (300 m), GBT (100 m)
– oversubscription: 1 – 10 x
– some travel and research funding
•
Private observatories (e.g., Palomar 5 m): semi-annual proposals
– guaranteed institutional time
– oversubscription: 1 – 2 x
– no funding
Observing Modes
• Flux measurements, detection:
– use imaging cameras on O/IR telescopes
– use single-dish radio telescopes
• Resolved imaging:
– use high spatial resolution imaging techniques
– use adaptive optics, O/IR/radio interferometry
• Spectroscopy
– use spectrographs of various spectral resolutions
(50 < λ/∆λ < 500,000)
Telescope Proposals
• Submitted 1 – 3 times / year, following
announcements of opportunity (AO)
– read AO carefully on instrument availability and
capability
• Between 4–10 pages
• Evaluated by Time Allocation Committees
(TAC; national or institutional)
– each proposal gets read in detail by at least 2
people: primary + secondary reviewer
– each proposal gets discussed and evaluated by
the entire TAC (6 – 8 people)
• Top-ranked proposals are awarded time
Idea
• Generate one
• Check what the required telescope
capabilities are
• See if and where these capabilities exist
• Check if similar observations were already
taken
– large facilities often have data archives
• Choose appropriate targets
• Apply for telescope time
Proposal Structure
• Cover sheet
• Scientific justification, 1–4 pp.
– describe the science case
• Technical justification, 1–2 pp.
– describe implementation of experiment
• Figures, tables, references
• Object list
Scientific Justification
• “Good proposals include some background on the
subject you are studying, in particular why anyone
not in your specific field should care. Then you can
explain what exactly you want to do, and why it will
solve every problem left in astronomy and find a cure
for the common cold. Adding good figures and tables
almost always makes a proposal stronger and easier
to understand for the reviewers.”
(Spitzer Space Telescope Science Center)
Technical Justification
• Describe the details of your planned
observations, scheduling constraints, data
analysis plans and how the technical plans
were validated.
• Include your estimate of the brightness of
your targets. Based on those brightness
estimates, include your estimate and
justification of what SNR values you need to
accomplish your science.
– online exposure time calculators can help
Dos and Don’ts
• Do read all relevant instrument and telescope
manuals before proposing
• Do contact any instrument contact person
before the deadline with questions
• Do write for a general scientific, but nonspecialist audience
• Do use figures to vividly exemplify the most
prominent or advanced concepts
• Do list your targets in a table, and estimate
exposure times for each target
Dos and Don’ts
• Do not play with the margins or fonts. This
annoys the reviewers. Unusual fonts do not
render on all systems.
• Don't change the font size of the major
headers either – large section header fonts
make the proposal easier to scan.
• Don't change the proposal format, really.
Every section has a purpose. Don't renumber
or reorder them.
More Proposal Resources
• A sample NOAO telescope proposal:
www.noao.edu/noaoprop/help/sample.pdf