Viking Frost
Because it dissapears soon after dawn, it's clearly volatile. Sulphates and other salts can't do this on Mars, so it must be either solid CO2 or solid H2O, Temperature measurements identify the latter.
Space/Science » in reply to re: Viking 2 picture in may 1979 (frost)
Because it dissapears soon after dawn, it's clearly volatile. Sulphates and other salts can't do this on Mars, so it must be either solid CO2 or solid H2O, Temperature measurements identify the latter.