The Mars Curiosity Rovers REMS instrument (Rover Environmental Monitoring Station) has sent back the first weather data from the red planet. REMS collects data about Mars‘ wind, pressure, temperature, humidity, and UV radiation.
From these measurements we can tell that the temperature on Mars fluctuates a lot. The daytime air temperature (blue line) is tolerable at -28 degrees Celcius (28 degrees Fahrenheit). But at night time it goes down to -75 degrees Celsius (-103 degrees Fahrenheit). It’s survivable, but is also a very hostile environment at night.
Mars’s atmospheric pressure fluctuates from 6.9 millibars (690 pascals) and 7.8 millibars (780 pascals). This is a very hostile environment for a human body to endure.
You won’t cook instantly like depicted in Total Recall above. The Suns harmful UV rays that are filtered by Earths atmosphere, well, there is no filter on Mars (PDF) so you will have serious health problems after exposure.
Curiosity’s REMS from Sol 9.5 to Sol 13:
Quick UV Facts from the WHO – EARTH
- Skin cancer is caused primarily by exposure to ultraviolet (UV) radiation – either from the sun or from artificial sources such as sunbeds.
- Globally in 2000, over 200 000 cases of melanoma were diagnosed and there were 65 000 melanoma-associated deaths.
- Excessive sun exposure in children and adolescents is likely to contribute to skin cancer in later life.
- Worldwide approximately 18 million people are blind as a result of cataracts, of these 5% of all cataract related disease burden is directly attributable to UV radiation exposure.
- Sun protection is recommended when the ultraviolet index is 3 and above.
In conclusion you could survive a few minutes on Mars exposed but even if you survive you will be very unhealthy and probably develop skin cancer due to the UV radiation. The temperature won’t kill you right away, but you would be in serious danger if you were exposed.