Space

First Moon radiation measurements reveal risk to astronaut health

First Moon radiation measureme...
The Chang'e-4 lander, as seen by the Yutu 2 rover
The Chang'e-4 lander, as seen by the Yutu 2 rover
View 1 Image
The Chang'e-4 lander, as seen by the Yutu 2 rover
1/1
The Chang'e-4 lander, as seen by the Yutu 2 rover

Radiation is one of the main dangers of space travel, and with renewed focus on sending human crews back to the Moon it’s important to understand the risks they face. Now we have the clearest data on that to date, thanks to a dedicated instrument onboard the Chinese lunar lander Chang’e-4.

Humans evolved to live on Earth, so we don’t fare too well as soon as you take us out of that environment. Low gravity can weaken muscles and bones, and beyond the protective bubble of our home planet’s magnetic field, radiation from the Sun and cosmic rays increase the risk of cancer, dementia and cardiovascular disease, among other things.

But exactly how much radiation would humans be exposed to on the Moon? Apollo astronauts carried instruments called dosimeters to measure that, but their exposure was measured over the entire trip. No direct detections have ever been conducted on the Moon until now.

When Chang’e-4 touched down on the far side of the Moon in January 2019, it was carrying the Lunar Lander Neutron and Dosimetry (LND) instrument with it. Researchers at Kiel University, the German Aerospace Center (DLR), and the Chinese Academy of Sciences have now reported the results of over a year of measurements from this instrument. The dosimeter was protected by about the same level of shielding as a spacesuit would offer a human, so the results should be fairly accurate, the team says.

The instrument recorded an equivalent dose rate of around 60 microsieverts per hour. That’s about 200 times higher than what we’re exposed to here on the ground, between five and 10 times more than you’d get on a long-haul flight, and about 2.6 times more than experienced by astronauts on the International Space Station.

There are ways to reduce that exposure though. Moon bases could be set up in huge caverns and lava tubes that are believed to sprawl underground, or shelters constructed of moon dust could provide adequate protection on the surface.

"We humans are not really made to withstand space radiation,” says Robert Wimmer-Schweingruber, second author of the study. “However, astronauts can and should shield themselves as far as possible during longer stays on the Moon, for example by covering their habitat with a thick layer of lunar soil.”

The team says that this more accurate reading can inform not just future crewed missions to the Moon, but also give a good starting point for better models of other planets like Mars.

The research was published in the journal Science Advances.

Source: University of Kiel

9 comments
FB36
IMHO, first base attempt should definitely be on the moon (for many good reasons), instead of Mars!

& IMHO, a (straight) half-tunnel would be way better than trying to find & use any lava tube (& also for many good reasons)!
For example, it could be bored & sealed w/ an airlock & filled w/ air (by remote control robots) before the arrival of the crew!
& going in & out (while carrying equipment), anytime, would be really easy; quite unlike any lava tube!

& once such tech is made working, then more such tunnel bases can be constructed around/nearby, again & again, as many as wanted/needed!
Kpar
FB36, your comments are spot on, but lava tubes already exist (as well as large underground caverns). Most sci-fi fans already knew of these hazards and predicted underground habitats many decades ago.
buzzclick
Surprised these tests hadn't been done before. It reminds me of one of the stories of the moon landings being fake because the astro nuts wouldn't have survived the cosmic rays. Moontan anyone? lol
Worzel
The same requirements will apply to Mars, as the moon, so it makes more sense to get the experience on the moon first, it's a lot cheaper and quicker to get there fore a start.
Graeme S
We humans are not really made to withstand space radiation, now that is the elephant in the room. We better get used to that concept and treat our planet and each other better, as this place we call home, Earth, is all we have and all where we were built for.
Nobody
This does seem odd that accurate radiation measurements weren't taken much earlier when the problem has been known for over 50 years and so many probes have been sent out since then. I've read many articles about the shielding problem and how they will solve it but so far not a lot of progress has been made. People going on extended missions to the moon and Mars will have to be moles but being an astromole doesn't sound too exciting.
piperTom
I'll echo the earlier commenters' theme "instead of Mars". While a "thick layer" of soil/rock can protect people on Luna and on Mars, the trip to and from Mars will not have any thick layer of anything. Don't go to Mars until the tech exists to go there FAST. Elon Musk will just have to wait.
ljaques
I have a strong feeling that human bodies could get used to more radiation in just a small amount of evolution. There are dozens of places on Earth which have 10x the standard radiation and people there have handled it without any problems. Granted, the type of radiation makes a big difference, but so many people think that the human body is vulnerable to ALL forms of radiation at any level, it's vexing.
Emil Atik
Besides, that both the German and Dutch space tech/space faring scientists have helped/supported with this not so (after all and in fact) domestically build Xi-Chinese rover with these utterly advanced (not overall US level, though, even it's advanced western countries) useful western technological equipments, like sensors and one other thing I just can't right, the film on the sails, I suppose, so a slightly, but significantly western influenced.. again.. China, give some few weirdly hidden credit to the Netherlands and Germany for achieving what you /it have achieved, when you/it landed on the far side of the moon and with this found as well, most definitely 👍💎🌈