NASA's Deep Space Habitat Could Support the Journey To Mars and a Lunar Return (spaceflightinsider.com)

MarkWhittington writes: Back in 2012, when NASA first proposed building a deep space habitat (DSH) beyond the moon, the Obama administration took a dim view of the idea. However, fast forward over three years, and the idea has become part of the Journey to Mars program. According to a story in Spaceflight Insider, the deep space habitat will be deployed in cis-lunar space in the 2020s to test various technologies related to sending humans to Mars. The DSH could also be part of an infrastructure that would support a return to the moon should the next administration decide to go that route.

Comments

Protection from Cosmic Rays?

[shoor]

Years ago I read an article somewhere about protection from Cosmic Rays. It made an impression, and what's also made an impression is that I don't think I've ever come across anything else about it in the discussions about plans to send people to Mars. I gather though, that cumulative damage from Cosmic Rays are a serious enough issue that it would be criminally negligent of the powers to be if they didn't offer protection. So, what to do about Cosmic Rays? This is from memory about what the article said and may not be quite right but:
1. 3 feet of water offers as much protection from Cosmic Rays as the earth's atmosphere (maybe it was the atmosphere as it is in Denver, Colo.) So a ship going to Mars could be sheathed in a water jacket. That's a lot of mass, but, the bigger the ship, the less the total percentage of mass would be dedicated to the water jacket. Also, the water could be used for drinking, then purified and recycled. (Also, since the article came out, I've read about water being found on the Moon. Getting water from the Moon for the water jacket might be more practical as it has less of a gravity well to be hauled up from.)
2. Alternatively, a very strong magnetic field around the ship would deflect the cosmic rays. This would be less massive. Methinks it would have to be a very powerful field and I'm wondering a bit at the technology to do it.