This may be common knowledge, but what the hell...
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Full Version: Galileo Images Of Saturn
It's certainly not that common, oh no.
Apart from the star trails, any idea what the blobs are? Titan, Enceladus, perhaps - and some dust!
Bob Shaw
Apart from the star trails, any idea what the blobs are? Titan, Enceladus, perhaps - and some dust!
Bob Shaw
I did a super-resolution image with Galileo-Saturn data. Here is a false color version utilizing a lot of infrared data.
Oops...posted twice....
QUOTE (Bob Shaw @ Jan 29 2006, 05:10 AM)
It's certainly not that common, oh no.
Apart from the star trails, any idea what the blobs are? Titan, Enceladus, perhaps - and some dust!
Bob Shaw
Apart from the star trails, any idea what the blobs are? Titan, Enceladus, perhaps - and some dust!
Bob Shaw
I think the blobs are probably radiation noise for the most part. I'm pretty sure Galileo resolved Titan, but the smaller moons, I don't know. Ted, I thought you might have done some work on these! That one is going in the favorite obscurities file...
QUOTE (Exploitcorporations @ Jan 29 2006, 12:23 PM)
I think the blobs are probably radiation noise for the most part. I'm pretty sure Galileo resolved Titan, but the smaller moons, I don't know. Ted, I thought you might have done some work on these! That one is going in the favorite obscurities file...
Titan is visible to the left of Saturn in my image. The other spots are noise in the raw data. Frankly, finding Titan required comparing multiple images.....It would have been risky only using one. I had a large archive of Galileo work...Sadly, much of it is lost, for now...However, due to the fact that it is pre-May 2004, it is on the hard drive of my old computer, so I should be able to recover it. But I have very few projects that compare to the spectacular mosaics you have been producing. Have you tried working with the I24 Dorian mosaic? I have a version among my lost data that I less-than-affectionatly referred to as my Dorian disaster. It was an overlay of the spotty I-24 data (and this set is particularly bad on top of what I think was C21 data. It had potential, but reprojecting images other than the most basic stretching and distortion was, at the time, beyond my know-how level.
Indeed little known! Apparently some other gas giant images are lurking in the data...
Klaasen, K.P., H.H. Breneman, A.A. Simon-Miller, D. Banfield, and G.C. Levanas, Final Calibration of the Galileo Solid-State Imaging System in Jupiter Orbit, Optical Engineering, 2002.
"3.3 Methane Filter Wavelength Calibration
"One of the important science objectives of the Galileo SSI investigation is to determine the vertical structure of the Jovian atmosphere. The narrow-band filters located in wavelength bands in which methane absorbs strongly played a key role in allowing the SSI images to probe to different depths of Jupiter’s atmosphere, which contains significant amounts of methane gas. However, knowledge of the exact location of the central wavelength of these filters is necessary to accurately calibrate the atmospheric depths to which each filter probes. Therefore, several attempts were made in flight to determine the central wavelengths of the two methane absorption band filters. These attempts used imaging of other gaseous planets having methane-rich atmospheres (primarily Saturn, but imaging of Titan, Uranus, and Neptune was also attempted) in the two methane band filters and the filter in the reflectance continuum between them (756-nm). The SSI measured radiance ratios based on the SSI spectral response model were then compared to those expected from ground-based photometric measurements of these bodies’ spectral radiances. Differences between these two measurements would then imply that the assumed central wavelengths of the SSI methane-band filters were incorrect, and the wavelength shift necessary to bring the measurements into agreement could be determined.
"Methane-band imaging of the giant planets was attempted on orbits E18, C22, and G29. On E18, only one 756-nm and one 727-nm filter image of Saturn were usable. The phase angle of Saturn was 28° for these images. On C22, several (3 - 5) images of Saturn at 19° phase were obtained in all three filters of interest – 727, 756, and 889-nm. And on G29, 7 good images of Saturn were obtained in each of the three filters at a phase angle of 17°. Problems with low signal-to-noise ratios (SNRs), excessive smear, and overlapping of Titan by Saturn due to pointing instabilities during the long exposure times necessary made the other attempted images unusable for this study."
Klaasen, K.P., H.H. Breneman, A.A. Simon-Miller, D. Banfield, and G.C. Levanas, Final Calibration of the Galileo Solid-State Imaging System in Jupiter Orbit, Optical Engineering, 2002.
"3.3 Methane Filter Wavelength Calibration
"One of the important science objectives of the Galileo SSI investigation is to determine the vertical structure of the Jovian atmosphere. The narrow-band filters located in wavelength bands in which methane absorbs strongly played a key role in allowing the SSI images to probe to different depths of Jupiter’s atmosphere, which contains significant amounts of methane gas. However, knowledge of the exact location of the central wavelength of these filters is necessary to accurately calibrate the atmospheric depths to which each filter probes. Therefore, several attempts were made in flight to determine the central wavelengths of the two methane absorption band filters. These attempts used imaging of other gaseous planets having methane-rich atmospheres (primarily Saturn, but imaging of Titan, Uranus, and Neptune was also attempted) in the two methane band filters and the filter in the reflectance continuum between them (756-nm). The SSI measured radiance ratios based on the SSI spectral response model were then compared to those expected from ground-based photometric measurements of these bodies’ spectral radiances. Differences between these two measurements would then imply that the assumed central wavelengths of the SSI methane-band filters were incorrect, and the wavelength shift necessary to bring the measurements into agreement could be determined.
"Methane-band imaging of the giant planets was attempted on orbits E18, C22, and G29. On E18, only one 756-nm and one 727-nm filter image of Saturn were usable. The phase angle of Saturn was 28° for these images. On C22, several (3 - 5) images of Saturn at 19° phase were obtained in all three filters of interest – 727, 756, and 889-nm. And on G29, 7 good images of Saturn were obtained in each of the three filters at a phase angle of 17°. Problems with low signal-to-noise ratios (SNRs), excessive smear, and overlapping of Titan by Saturn due to pointing instabilities during the long exposure times necessary made the other attempted images unusable for this study."
QUOTE (vexgizmo @ Feb 2 2006, 07:37 AM)
Indeed little known! Apparently some other gas giant images are lurking in the data...
Yes, but the Neptune and Uranus images are noisy and so small, perhaps unresolved, that they really don't amount to much.
Cool pics, all. I had no idea... 
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