73 votes
Accepted

Why don't we shield existing CPUs from radiation instead of designing new ones?

Because shielding against radiation is heavy, and weight is the enemy of getting things into space. CPUs are quite sensitive to radiation, and some types of radiation (cosmic rays) are not only quite ...
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  • 3,382
67 votes

How did Apollo missions solve the cosmic radiation problem?

While cosmic radiation is a problem, it's the same as with radiation on Earth: the risk is cumulative. The levels were low enough that missions of 1-2 weeks at this level did not pose a big health ...
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  • 121k
66 votes
Accepted

Why can't we use the same radiation shielding in Mars that we used when going to the moon?

Radiation exposure is a cumulative risk. The more radiation you receive, the more likely you are to develop cancers. The Apollo missions took no more than two weeks to complete; the astronauts ...
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66 votes

Why can't we use the same radiation shielding in Mars that we used when going to the moon?

In addition to what Russell Borogove says about cumulative risk you're operating under a false assumption--that there was shielding on the Apollo capsules. Not only did the Apollo capsules not have ...
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59 votes
Accepted

Can we power things (like cars or similar rovers) on earth in the same way Perseverance generates power?

RTG technology has been applied on Earth, many times, although not for transportation - they don't produce much power for their weight so any RTG powered vehicle would be very slow. Some pacemakers ...
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  • 18.7k
53 votes

How did Apollo missions solve the cosmic radiation problem?

They didn't, which is why the Apollo astronauts saw blinding flashes inside their eyes during the mission and then had a much higher probability of suffering from cataracts later in life. The flashes ...
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49 votes

How did the Apollo guidance computers deal with radiation?

TL;DR: It was so busy getting stuff done, it didn't care. Being old, slow, massive and inefficient (by any modern standards, not by those in 1965) is a huge benefit when it comes to radiation hardness....
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  • 12.7k
47 votes

How did Apollo missions solve the cosmic radiation problem?

Apollo solved the cosmic radiation problem in a counter-intuitive manner: by minimizing shielding. Most cosmic rays are very-high-energy atomic nuclei; the rest are very-high-energy protons. When ...
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  • 11.5k
37 votes
Accepted

How was it possible for the Apollo 11 to film and take pictures with such radiation?

The radiation dosage for a year on the moon is between 110 mSv and 380 mSv. On Earth, that dosage is 2.4 mSv, or higher, depending on where you are exactly. Bottom line, the few days in Lunar orbit ...
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  • 118k
28 votes

Can we power things (like cars or similar rovers) on earth in the same way Perseverance generates power?

RTGs are expensive to produce, can be politically inconvenient to use, and in the form of a plutonium-bearing device, represent a potential nuclear proliferation hazard (though all RTGs might be used ...
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27 votes
Accepted

How does steel deteriorate in translunar space?

The spectral data came from the surface of the material only a few atoms thick which is exposed to hard vacuum. The solar wind has ions of many materials. It is mostly hydrogen, which as an ion is ...
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26 votes

How much UV radiation will Mars inhabitants receive?

tl;dr: The UV index is primarily concerned with the level of UV-A that can cause sunburn and, potentially, skin cancer. The actual UV-A flux at Mars is not dramatically different from that at Earth (...
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  • 2,541
24 votes
Accepted

Does Curiosity pose a radiation hazard for would be colonists?

At first glance, the RTG does not pose a risk. It is powered by Pu-238, which is primarily an alpha emitter throughout its decay chain. Alpha particles can be stopped by a sheet of paper. An ...
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  • 121k
24 votes

If colonists burrowed far enough under the ice on Ganymede or Europa, would the ice provide adequate protection for them from Jupiter's radiation?

Yes, it absolutely would! The radiation on Europa is about 5.4 Sv (540 rem) of radiation per day. Looking at this guide, and assuming you want to meet OSHA standards of 5 rem per year, you would need ...
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  • 118k
21 votes

How was it possible for the Apollo 11 to film and take pictures with such radiation?

Radiation can affect film - but bear in mind the radiation around Chernobyl was, truly, extremely high. The radiation in our region of space is not as extreme. Also bear in mind that the earlier ...
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  • 5,148
19 votes
Accepted

Did the Apollo missions fly "over the top" of the Van Allen radiation belts?

Not exactly "over the top" (still through the outer portion of the belts), but yes, it appears so, according to this source. There are simplified trajectory plots shown in the link. Also this source ...
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18 votes
Accepted

Do astronauts only perform spacewalks while the ISS is on the night side of the Earth?

No. Most International Space Station (ISS) spacewalks last in the order of several hours, often up to 8 hours during more difficult and time-consuming repairs and installations, and some nearly 9 ...
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  • 75.3k
18 votes

How was it possible for the Apollo 11 to film and take pictures with such radiation?

NASA studied the effects of radiation on film. Bright spots are just one of the possible results. Other effects include an increase in the amount of noise, and a decrease in contrast and color ...
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  • 121k
18 votes
Accepted

Can we survive Van Allen belt radiation?

A satellite shielded by 3 mm of aluminium in an elliptic orbit (200 by 20,000 miles (320 by 32,190 km)) passing the radiation belts will receive about 2,500 rem (25 Sv) per year (for comparison, a ...
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  • 974
18 votes

How does steel deteriorate in translunar space?

Light interacts with fresh metal surfaces in only the first few atomic layers. What makes metals "metals" is the very high electron density, and we can think of that electron "plasma&...
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  • 148k
17 votes
Accepted

Would a nuclear propelled spaceship still need a storm shelter?

The basic idea here is to turn to have the shield you have towards the Sun. That does actually work, because the radiation from the Sun is directed, with a few exceptions: First, inside a planetary ...
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17 votes
Accepted

How does ISS protect astronauts from Coronal Mass Ejections?

The two specific modules are protected by two mechanisms: TeSS Polyethylene radiation protection tiles and bricks Water storage bags attached to the walls making a "water wall" High densities of ...
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16 votes

Is a Moon-base inherently more dangerous than a Space Station?

If it is more dangerous, how much more and in what ways? Proffesorfish and Eli Skolas have both given thoughtful answers comparing the hazards of I.S.S. vs Moonbase. If humans were preceded by robots ...
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  • 15.1k
16 votes

How are astronauts protected from radiation in a spacecraft?

This may sound strange, but part of the protection is a lack of shielding. The high-energy particles that make up a large portion of the radiation environment mostly just pass through the human body. ...
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  • 11.5k
16 votes
Accepted

Does the ISS medical inventory include a sun-tan/sunscreen lotion/cream?

Ultraviolet radiation does not get through the aluminum hull of the space station, so no such protection is needed for the crew inside. The glass of EVA suits is made not to let UV light through, ...
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16 votes

How big is the risk/potential damage from radiation on a Mars trip?

If you just stay here on Earth, you have an 18% chance of dying of cancer. Let's first consider a one-way trip, ignoring solar flares and radiation after you land. So just consider the cosmic rays, ...
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  • 57.5k
16 votes
Accepted

Could ozone be used in a biodome on Mars?

If we have $O_2$ lighted with UV, we have actually many reactions working together: $O_2 + \gamma \rightarrow 2O$ $O_2 + O \rightarrow O_3$ $O_3 + \gamma \rightarrow O_2 + O$ $O + O_3 \rightarrow 2 ...
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  • 3,234
15 votes

How did the first US manned Moon mission suits block radiation?

The Van Allen belt radiation was primarily shielded by the hull of the spacecraft, not the space suits. The electrons were mostly absorbed by the aluminium. Of the protons, however, some would ...
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  • 1,668
14 votes

What materials provide the best protection from cosmic radiation?

With respect to potential travel in our own solar system there are two general types of radiation that have our concern! The first type of radiation is solar radiation, which mostly consists of low- ...
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  • 494

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