# For how long could astronauts stay on the surface of Europa, Jupiter's moon, with our current latest and most advanced spacesuit before dying?

Is it possible for astronauts to land on Europa safely?

Given the fact that radiation level on Europa is about 5.4 Sv (or about 540 rem) per day and the temperature is around -260 °F (or about -160 °C).

--> Assume astronauts somehow land successfully on Europa and are equipped with the latest and most advanced spacesuit as of 2022. For how long could they stay on the Europa's surface before the radiation level and the cold temperature get out of hand and potentially kill them in process?

• "equipped with the latest and most advanced spacesuit version in 2022" – Sadly, the "latest and most advanced spacesuit version in 2022" is basically the same as 1964, when the contract for the Apollo spacesuits was awarded. The EMUs that are used on the ISS are the same ones as the ones used for Shuttle, which are closely related to the ones used on Apollo and Skylab. The effort to develop a successor is so far above budget and behind schedule that it was restarted just this year, but was again awarded to (some of) the same compan(y/ies) that already built the Apollo-Skylab-Shuttle-ISS ones. Nov 13, 2022 at 12:30
• Same for the Russian Orlan: it is essentially from 1967. And if you were hoping to look to China or India: they just bought the Orlan. Nov 13, 2022 at 12:33
• Linking a related post (and comments underneath) discussing this from two of the best experts on this site! Nov 13, 2022 at 18:24
• – uhoh
Nov 13, 2022 at 21:19
• – uhoh
Nov 13, 2022 at 21:19

## About Four Minutes

The OSHA safety limit for radiation is 5 REM per year. With a surface radiation is 540 REM, you'd hit the OSHA limit at about 3 minutes 45 seconds.

Space suits provide negligible radiation protection. To understand how little, consider the tenth thickness of lead is 4 cm (1.5 inches). For a space suit to increase one's stay time from 4 minutes to 40 minutes, it would need to be made of 1.5 inch thick lead plate!

## Or One Day if you're Ruthless

A 6 Sv dose has about a 50% survival rate, assuming you can get medical treatment quickly. (Gy and Sv are equivalent for this kind of rough math.)

So your crew could stay for a day if you're willing to have half of them die on the way home.