2
$\begingroup$

This question already has an answer here:

What are current ways in which astronauts and spacecrafts are protected from radiation? Are their any new ways/ideas to limit the amount of exposure to radiation?

$\endgroup$

marked as duplicate by DrSheldon, DarkDust, Jan Doggen, Amar, Brian Tompsett - 汤莱恩 Nov 30 '18 at 14:41

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • $\begingroup$ One of the main methods is time. I don’t think we’ve really solved the radiation protection problem fully, so limiting exposure is the best way to protect them. If i’m not mistaken, i think the general way to protect astronauts is to let radiation transmit through them rather than using a shield that absorbs or reflects it. I’m not sure about spacecraft though. $\endgroup$ – Paul Nov 24 '18 at 20:30
  • $\begingroup$ Thanks Paul, but aside from time, what can we physically utilize to assist astronauts. Such an pills etc.... $\endgroup$ – PlusModel Cheryl Joseph Nov 24 '18 at 20:32
  • $\begingroup$ Related: space.stackexchange.com/questions/31820/… $\endgroup$ – Paul Nov 24 '18 at 20:33
  • $\begingroup$ Also related (it looks like hydrogen can be used as a shield when necessary) space.stackexchange.com/questions/1/… $\endgroup$ – Paul Nov 24 '18 at 20:38
  • $\begingroup$ Sola dosis facit venenum. The dose makes the poison. $\endgroup$ – RonJohn Nov 25 '18 at 0:33
3
$\begingroup$

So currently we don't actually do anything to protect them from radiation (if we exclude the basics like UV shields and being able to alter the attitude of the craft to place the highest density of metal/solar arrays/whatever in the direction of the incoming radiation) As Paul mentioned, limiting the amount of time spent in space is pretty much it. NASA have researched the use of various shields such as water etc, but the mass cost is still prohibitive.

Those astronauts who have spent long terms on the ISS are extensively studied to understand the impact on them, but they aren't protected.

$\endgroup$
  • $\begingroup$ I think that ISS has procedures for solar events such as CMEs, but I don't know if those have any radiation-mitigating effect or if they just address problems if electronic systems fail. Possibly related: space.stackexchange.com/a/1040/12102 $\endgroup$ – uhoh Nov 25 '18 at 0:24
  • 1
    $\begingroup$ I think you are correct @uhoh - all I can find indicates electronic system resilience $\endgroup$ – Rory Alsop Nov 25 '18 at 10:01
2
$\begingroup$

The ISS orbits between 205-270 miles (330-435 km) above the Earth at an inclination of 51.64 degrees. That's low enough that it can get by with minimal (read: basically no) shielding, because Earth provides all that it needs. For deep space settlements, roughly 7 tons of water per m^2, or 11 tons of lunar regolith per m^2, is required to shield something outside of Earth's protection against every type of radiation. The Van Allen belts themselves stretch from ~400 miles (650 km) to 36,000 miles (58,000 km), so a habitat located below the belts can use minimal shielding, while one above would require the full protection (and thus considerable added mass, potentially in the millions of tons). The International Commission on Radiation Protection sets the limit for yearly exposure to radiation at 20 milliSieverts, and for pregnant women, the limit is 6.6 milliGrays (Grays are a measure of radiation absorbed). Polyethylene is also an option for radiation shielding, and is slightly better than water.

Sources:

$\endgroup$

Not the answer you're looking for? Browse other questions tagged or ask your own question.