We select 6 nights and extract albedos in 4 bands:
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Here are albedos determined for 6 nights. We see 4 filter bands (VE2 is still being processed). Each color represents one night. There are 3 determinations of albedo from each image – hence points come in columns of three.
1) Albedos can differ in level from night to night – e.g. blue and red in panel 1.
2) Albedos can also be almost constant during a night – e.g. purple and green points in panel 1 vs red or blue.
3) Some nights have large scatter – e.g. green vs blue
4) B albedos are higher than V and others
5) VE1 and IRCUT albedos are very similar – the filters are also very similar, so this is good for reproducibility.
6) While some albedos evolve smoothly on a given night IRCUT shows a ‘dip’ – e.g. blue crosses in B vs blue points in IRCUT
Questions of interest:
a) Why are some nights noisy? E.g. the green points. Information on airmass, alfa and bias frame statistics, and RON, are available.
b) Can the nightly evolution (i.e. slope) of the points be related to anything happening on Earth?
c) Can the change in slope in IRCUT be related to anything special?