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Yeah, that's nonsense. The radiation in low Earth orbit is only a bit less than above the magnetosphere, and most of that difference is from shadowing by the

by pfdietz 10mo ago

Yeah, that's nonsense. The radiation in low Earth orbit is only a bit less than above the magnetosphere, and most of that difference is from shadowing by the Earth itself. In contrast, there's a massive decrease in radiation from LEO to to sea level. Radiation at ISS: 144 mSv per year Radiation on a trip to Mars: ~340 mSv per year Cosmic radiation at sea level: about 0.4 mSv per year The atmosphere is doing the heavy lifting in shielding us from cosmic radiation, not the magnetosphere.

magicalhippo 10mo ago
> Radiation at ISS: 144 mSv per year > Radiation on a trip to Mars: ~340 mSv per year This seems to track with research that during a geomagnetic excursion[1], where the field strength dropped to about 10%, the cosmic radiation seems to have roughly doubled[2]. [1]: https://en.wikipedia.org/wiki/Geomagnetic_excursion https://en.wikipedia.org/wiki/Geomagnetic_excursion [2]: https://www.eurekalert.org/news-releases/1041098 https://www.eurekalert.org/news-releases/1041098
- pfdietz 10mo ago
  To steelman the argument, perhaps what the magnetosphere is doing is stopping the atmosphere from making too much carbon-14. In shielding the surface from energetic cosmic rays, neutrons are produced, and these transmute N-14 to C-14 by the (n,p) reaction.
andsoitis 10mo ago
> Yeah, that's nonsense. Assuming you're right, why do you suppose so many publications get it wrong? Not only the NASA one I linked to but also Wikipedia for example: https://en.wikipedia.org/wiki/Cosmic_ray https://en.wikipedia.org/wiki/Cosmic_ray Or the European Space Agency: https://www.esa.int/Science_Exploration/Space_Science/Cluster/Cluster_s_20_years_of_studying_Earth_s_magnetosphere https://www.esa.int/Science_Exploration/Space_Science/Cluste... You will forgive me if I take their assessment more seriously than yours, but I'm open to correcting my understanding.
- pfdietz 10mo ago
  It's in the interest of NASA (and the ESA) to hype the importance of the magnetosphere. After all, they are given money to investigate it, so the more important it is perceived, the more money they can expect to get.
  - andsoitis 10mo ago
    > It's in the interest of NASA (and the ESA) to hype the importance of the magnetosphere. After all, they are given money to investigate it I don’t know that that is a good reason to cause you to you think they’re lying. NASA also extensively investigates Earth's atmosphere. They use missions like Aura, CALIPSO, and upcoming ones like AOS and INCUS to monitor ozone, clouds, aerosols, and storms, providing crucial data for forecasts and climate science.
    - pfdietz 10mo ago
      They aren't "lying", they're "stretching the truth". I don't know why you'd expect a self-interested organization to do anything else.

by pfdietz 10mo ago

magicalhippo 10mo ago

> Radiation at ISS: 144 mSv per year > Radiation on a trip to Mars: ~340 mSv per year This seems to track with research that during a geomagnetic excursion[1], where the field strength dropped to about 10%, the cosmic radiation seems to have roughly doubled[2]. [1]: https://en.wikipedia.org/wiki/Geomagnetic_excursion https://en.wikipedia.org/wiki/Geomagnetic_excursion [2]: https://www.eurekalert.org/news-releases/1041098 https://www.eurekalert.org/news-releases/1041098

pfdietz 10mo ago
To steelman the argument, perhaps what the magnetosphere is doing is stopping the atmosphere from making too much carbon-14. In shielding the surface from energetic cosmic rays, neutrons are produced, and these transmute N-14 to C-14 by the (n,p) reaction.

andsoitis 10mo ago

> Yeah, that's nonsense. Assuming you're right, why do you suppose so many publications get it wrong? Not only the NASA one I linked to but also Wikipedia for example: https://en.wikipedia.org/wiki/Cosmic_ray https://en.wikipedia.org/wiki/Cosmic_ray Or the European Space Agency: https://www.esa.int/Science_Exploration/Space_Science/Cluster/Cluster_s_20_years_of_studying_Earth_s_magnetosphere https://www.esa.int/Science_Exploration/Space_Science/Cluste... You will forgive me if I take their assessment more seriously than yours, but I'm open to correcting my understanding.

pfdietz 10mo ago
It's in the interest of NASA (and the ESA) to hype the importance of the magnetosphere. After all, they are given money to investigate it, so the more important it is perceived, the more money they can expect to get.
- andsoitis 10mo ago
  > It's in the interest of NASA (and the ESA) to hype the importance of the magnetosphere. After all, they are given money to investigate it I don’t know that that is a good reason to cause you to you think they’re lying. NASA also extensively investigates Earth's atmosphere. They use missions like Aura, CALIPSO, and upcoming ones like AOS and INCUS to monitor ozone, clouds, aerosols, and storms, providing crucial data for forecasts and climate science.
  - pfdietz 10mo ago
    They aren't "lying", they're "stretching the truth". I don't know why you'd expect a self-interested organization to do anything else.