Payload specialist Marc Garneau displays a Canadian made Sunphotometer, part of a package of experiments which he is concentrating on during this mission. He is sitting on the Challenger's flight deck at the aft station.

View of the SIR-B antenna being deployed during STS 41-G. The Challenger's payload bay is open and the remote manipulator system (RMS) arm is in the stowed position at the right of the view.

41G-03-008 (5-13 Oct. 1984) --- The end effector of the space shuttle Challenger's remote manipulator system (RMS) taps against the shuttle imaging radar's (SIR-B) antenna to secure it during NASA's 41-G mission. Photo credit: NASA