Presentation on theme: "Stardust-NExT Mission Data Review Matthew Knight December 13, 2011."— Presentation transcript:
Stardust-NExT Mission Data Review Matthew Knight December 13, 2011
Raw NavCam Images Purpose of the dataset: archive the raw images from NavCam during Stardust NExT (12/2010-2/2011) as well as calibration image from 2007-2011 Additional data: catalog files, documentation on the calibration process/shutter behavior/flat field response/etc.
Overview of review Documentation is very thorough and well written –Explanations are sufficient –Supplemental information supplied is relevant Data are clearly laid out and easy to understand what is there Only needs minor fixes: –A small number of typos –A handful of science suggestions
Acronyms A number of acronyms were used at various times in many different files either without a definition or so long after the definition was given that I had forgotten what it meant. It would be useful to have a central repository with acronym definitions, perhaps in aareadme.txt or another file at that level. This goes for all three data sets I reviewed Example: I didn't figure out that EDR stands for "Edited, raw data record" until I saw it in stardust-cal-nc-2-preflight-v2.0/document/onlabels.txt This also allows me to infer that RDR must stand for "raw data record"
Catalog/navcam.cat What does “blocking” mean? Are the blocking values in Ang rather than nm? NH2: should I interpret this as “less than 10^-2 for wavelengths less than 6500 and longer than 6800; less than 10^-3 for wavelengths shorter than 6450 and longer than 6850?”
Catalog/navcam.cat Same interpretation for Oxygen? For C2 –Does this mean “less than 10^-1 from 3000 to 5051 and 5230 to 11000”? –Same notation should be used throughout (“,” here but “-” later) –At what wavelengths are these transmissions valid?
Catalog/navcam.cat Similar questions for YELLOW, RED, NIR Should HIRES be 3000- 4800 (not 3000-480?) Note the “nanometers” statement at the bottom Are these transmission curves given somewhere else (if so, please mention where)? –Plots: sdu-c_cal-navcam-2- next-tempel1- v1.0/document/olddoc/calibrpt.pdf –Ascii: stardust-cal-nc-2- preflight- v2.0/document/stardust/calrpt
Catalog/navcam.cat Is the new look-up table archived here? Where?
Catalog/next.cat What happened to 2011-2-14, 2011-2-16? –Should all of the mission phases be consecutive or is it okay to have gaps?
Catalog/dataset.cat “Data collection periods” section has write ups of “Checkout, Cruise 5, and Cruise 6” and “Encounter”, but not “Approach” or “Departure”. Is this intentional?
Document/nc_cal_overview.* Why is the calibration procedure called “decalibration” instead of “calibration”? –Klaasen et al. (2011) call it “calibration”
How might I use the data? Make a flyby movie (raw data) Very easy to do with all images in ds9
How might I use the data? Measure a lightcurve of the comet –Problem: I’m not sure where the comet is except very close to flyby. –Suggestion: Make a table with the position of the comet in each image X,Y position or RA,dec is okay with me Lightcurve will be shown in Calibrated section
Calibrated NavCam Images The same as raw NavCam images, except these have been calibrated Documentation is virtually identical –All comments were given in Raw NavCam presentation
Calibrated NavCam Images Why doesn’t the calibration get rid of the striping?
How might I use the data? Make a lightcurve of the comet on approach Method: find comet, measure photometry from images, extract distance to spacecraft and date from header Result: rotation visible, change in spatial scale evident
NavCam Ground-based Calibration Data Contains the raw, preflight, thermal- vacuum calibration images –Testing at various temperatures, exposure times, radiances Review summary: –Documentation is very thorough and well written –Minimal typos; no problems using the images for science –Easy to understand what was there
How might I use the data? Measure the flux as a function of T –Read in fits files –Took the median of the whole image to get the flux –Got temperature, radiance, exposure time from the headers
How might I use the data? Measure the flux as a function of T –Result: corrected for radiance to get a better correlation