I recently watched ep 2 of the National Geographic miniseries 'Mars', and one of the major plot points was the danger posed to the astronauts by the cold temperatures of the planet, especially at night. It's common in popular media to portray Mars being a dangerously cold place, and the numbers seem to support that - average temperatures around -55 C.
But with only 1% of the atmosphere of Earth, it would seem the effect of convective heat loss would be significantly lower than what we're used to. I also recall from thermodynamics courses (vaguely, as it was a half a lifetime ago) that a properly insulated body loses heat very slowly due to radiative heat transfer. If these assumptions are accurate, it seems possible that a person in a suit designed for survival on Mars would stay warm with moderate activity, and may actually overheat without active cooling systems, regardless of the outside temperature.
So am I missing something, or is the cold on Mars not as big a challenge as portrayed in popular media?
But with only 1% of the atmosphere of Earth, it would seem the effect of convective heat loss would be significantly lower than what we're used to. I also recall from thermodynamics courses (vaguely, as it was a half a lifetime ago) that a properly insulated body loses heat very slowly due to radiative heat transfer. If these assumptions are accurate, it seems possible that a person in a suit designed for survival on Mars would stay warm with moderate activity, and may actually overheat without active cooling systems, regardless of the outside temperature.
So am I missing something, or is the cold on Mars not as big a challenge as portrayed in popular media?
via International Skeptics Forum http://ift.tt/2gNtRN6
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