Posted on 01/15/2007 7:39:49 PM PST by KevinDavis
NASA is studying better ways for astronauts to exercise in space after long-running medical tests on International Space Station (ISS) crewmembers revealed significant bone loss rates.
Tests indicate bone loss rates of up to 1.5% a month, "or about as much as a post-menopausal woman loses per year", says Julie Robinson, acting ISS programme scientist at NASA Johnson Space Center. The results mean that, unless bone loss rates can be countered, a prolonged Mars mission would be virtually untenable for humans.
(Excerpt) Read more at flightglobal.com ...
What??? (I'm focusing on the post-menopausal women part.) Is that for women with osteoporosis? Or is that a factor of post-menopause itself? That's a pretty staggering percentage of bone loss. So, in 10 years a woman would lose 15% of her bone mass? And in 20 years, 30%?
How about a new form of propulsion to get there faster? I saw a piece on NASA TV on former astronaut Franklin Chang-Diaz. He's working with a team to develop an ion propulsion system to be used on such a manned trip. As far as bone loss is concerned, the studies of long stay astronauts and cosmonauts would give a good indication. Cosmonaut Sergei Krikalev holds the record for total time on orbit at 800+ days. Him and Dr. Valery Polyakov are two prime subjects. Polyakov spent 14 straight months in orbit aboard Mir. He did it to find out the lasting effects of such prolonged weightlesness.
A better propulsion system would go a long way to help humans go a long way faster.
The problem with getting there faster is that you have to accelerate to a faster speed and then decelerate again from that speed. At lower speeds, aerobraking into the atmosphere is feasible, at higher speeds you need to carry extra propellant which means larger engines which means more propellant, ad nauseum.
I think artificial gravity is the way to go. Just spin her up really good at 1 or 2 rpm and you're all set.
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