| Spectroscopy of Jupiter albedo colors and reflectances by Christophe.P |
Here are some results obtained with the Aply600 spectroscope on Jupiter. To summarize: 1) I have been able to obtain a full albedo spectrum by summing 9 individual spectra taken over the different domains of the planet (slit width = 23ƒÊm and 5"). No solar star was observed (too faint, it failed) and so the albedo has been found first by the spectrophotometry method (apparent magnitudes taken from a flux spectrum), then by calculating normalized magnitudes, and then the photometric albedos. Vmag was -2,88 that night (ephemerides: -2,86). More explanations are on the graph. The comparison with the reference from Erich Karkoschka show a correct profile but a noticeably slope difference. This would more likely come from an error while correcting the instrument's response ; but despite looking for it I have not been able to find one. I have also some data taken with photometric filters ; this could help me to evaluate if and how the slope is really wrong! 2) I'm adding a simple color spectrum of the planet, just like we see it through eyes and camera. 3) Finally, I have tried to compare the relative individual reflectances of the different domains observed. The third graph correctly finds the NEB and EZ to be darker in the blue wavelengths; but the 5" wide slit is a bit too wide to discriminate the more narrow temperate domains. The relative high blueness of the NPR looks surprising but a clear haze can be observed over it on B and UV images and so it must be real...
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