GOES-8 Sounder -- Example of all 19 Channels

20-panel loops of all 19 GOES-8 sounder channels over the eastern U.S.:

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The visible channel (Channel 19) -- although in color -- does easily provide the night-day flag.
Channels 1 and 2 show thermal gradient reversal at the tropopause.
Only the highest clouds are evident in Channel 3; more cloud appears as one goes to the lower sensing channels (4,5,6...).
Channels 3, 12, and 15 are all seen at about the same "altitude" (similar color range) but in different spectral regions (or "absorption bands"): Longwave CO2, Midwave H2O, Shortwave CO2.
Relative transparency is evident across (window) Channels 6, 7, 8, 17, and 18.
Channel 9 (ozone) is similar but different from Channel 10. Channel 12 looks much cleaner than "sibling" Channels 3 and 15; Channel 11 is even sharper looking.
Over a long enough period (2 days), the large scale deep tropospheric thermal pattern (the "ridging" evident in Channels 3-5) can be seen to be slowing moving eastward.