'Mouse-Tronaughts' to Test Low-Gravity in Space

RandBlade writes "The Telegraph has an article about plans to launch mice into space with simulated low-gravity for five weeks, to test the effects of low-gravity on their bodies. This "will be the first time mammals of any kind have lived in partial gravity for an extended period." Hopes are that this will provide information useful for plans to launch men to Mars, which has one-third of the gravity of Earth."

Comments

Animal Cruelty

[queen of everything]

I'm sure we'll have lots of posts about "animal cruelty". Is it better to test on mice or humans? Which life is worth more? Would it be fair to send humans to Mars and just watch their bodies essentially turn to jello from the lack of gravity? Those that spent time on the ISS are dealing with the consequences of little or no gravity for an extended period of time.

I'm not saying that it is necessarily "right" to test on animals, but from a scientific point of view, it will bring us much closer to knowing the effect of the conditions on Mars and will bring us closer to having manned missions and even maybe a space station there one day.

Re:Pardon?

[Gojira Shipi-Taro]

I think you missed the bit about "simulated low gravity." They're not going to be in "zero-g" or microgravity.

The point of the experiment, if I understand it correctly, is to determine to what degree a low gravity (as opposed to micro-gravity, which is what the space stations experience) environment differs in effect on mammals from Full Gravity and Micro-gravity environments.

Re:They contradict themselves in the article

[NeoThermic]

>> If you have a calculator, determine the force from gravity applied to a human on earth. Then, calculate again from 1,000 km away. It's a small difference.

Sure! I'm Game!


Now, if a body of mass m is a distance r from the center of the earth, you know that the weight of the body is F given by the formula F=GmM/r^2 The gravitaional field strength is g = F/m = (GmM/r^2)/m = GM/r^2

(With me sofar?)

g=GM/r^2
= 6.7 * 10^-11 N m^2 kg^-2 * 6.0 * 10^24 kg/(6.4 * 10^6)^2
= 9.814 N kg^-1

Notice! We get a value which is gravity at earths surface...

Ok, so with the poster above... lets add on our 1,000 km ...

g=GM/r^2
= 6.7 * 10^-11 N m^2 kg^-2 * 6.0 * 10^24 kg/(6.401 * 10^6)^2
= 9.811 N kg^-1
Yes, we lost all of 0.001 N kg^-1... our poster above is right.

So, how can they make this worth while? Easy. Make them do a larger orbit, so that they are twice the distance r from the earth (notice above, you have to measure from the center of the earth...)

So, lets see how much N kg-1 our mice would have if they were twice as far out...

g=GM/r^2
= 6.7 * 10^-11 N m^2 kg^-2 * 6.0 * 10^24 kg/(12.8 * 10^6)^2
= 2.453 N kg^-1

Anyway, enough maths...
NeoThermic