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jkmccrann
2006-Apr-29, 02:39 AM
Just a simple question, which of these do you think you'd have more fun in?

The Zero gravity of Outer Space?

The Very Low Gravity of a place like the Moon?

Or the Slightly Higher Gravity of a place like Mars?

For me, that's a tough question - but at the moment, I might just plumb for the Moon.

antoniseb
2006-Apr-29, 02:49 AM
All three would be fun in their own way. I voted for the Moon (inside an air filled dome or cave) because it would be fun to do things that would be impossible on the Earth, but still like things I do on Earth, so I can feel great about it.

Doing things in zero-G would be really cool too, but there I'd be doing things that aren't like anything I've done before, and some aspect of the fun would be gone.

ToSeek
2006-Apr-29, 03:11 AM
I'd really like to give zero-G a try, and I've got a better shot at doing so than getting to the Moon or Mars.

HenrikOlsen
2006-Apr-29, 06:15 PM
When you wrote Slightly Higher Gravity of Mars, I read it as slightly higher that here, rather than slightly higher than the Moon, and got rather confused.:)

With ~3.73 m/s2, it's more than twice the surface gravity of the moon so I wouldn't call in slightly higher.:)

Personally I think Venus with its 8.802 m/s2 would be best, just enough lighter to make me feel really strong, but not enough to make walking too difficult.

jkmccrann
2006-Apr-30, 08:08 PM
When you wrote Slightly Higher Gravity of Mars, I read it as slightly higher that here, rather than slightly higher than the Moon, and got rather confused.:)

With ~3.73 m/s2, it's more than twice the surface gravity of the moon so I wouldn't call in slightly higher.:)

Personally I think Venus with its 8.802 m/s2 would be best, just enough lighter to make me feel really strong, but not enough to make walking too difficult.

Oh, more than twice as high as the Moon! I didn't know that, thanks for the tip though.

Only issue I see with Venus is I can't imagine anyone strolling along the Venusian surface anytime soon! ;)

For the others, your odds are better than you get in the lottery. I think?

mugaliens
2006-May-01, 03:50 AM
I hate Mars. But the gravity's better for my bones.

Earth's gravity is best, but that wasn't one of the choices!

zebo-the-fat
2006-May-01, 12:15 PM
Zero G would be fun, but not good for long term health!

Gruesome
2006-May-01, 02:48 PM
Out of the two choices, I chose the moon.

I say two choices because 'zero gravity' doesn't exist. Gravity is unavoidable. This being an astromony board, I'd expect you all to know that. sheesh.

jkmccrann
2006-May-01, 03:29 PM
Out of the two choices, I chose the moon.

I say two choices because 'zero gravity' doesn't exist. Gravity is unavoidable. This being an astromony board, I'd expect you all to know that. sheesh.

Yes, I realise that mate, but for all intents and purposes when one is in outer space one can consider there to effectively be zero gravity.

Given you obviously regard the level of gravity one would have free-floating in outer space as significant can you provide me with a figure for the level of gravity one experiences at a place like the ISS? Expressed in this notation, ??.? m/s 2

And at what level of significance would you accept expressing the gravity as zero gravity?

Gruesome
2006-May-01, 03:44 PM
Given you obviously regard the level of gravity one would have free-floating in outer space as significant can you provide me with a figure for the level of gravity one experiences at a place like the ISS? Expressed in this notation, ??.? m/s 2

Probably not. ;)

I did not mean to insinuate that gravity acting upon a person in the ISS would be significant, just that it would not be zero. Small, yes. But not zero.

Just picking a nit, that's all. :)

Edited to add:

Actually I can give you the gravity acting on a person in the ISS. 9.8 m/s2. It is the precise velocity of the craft, acting in conjunction with Earth's gravity that give the illusion of 'zero gravity'. If, in fact, no gravity was acting on the ISS, it would sail off into space. Right?

HenrikOlsen
2006-May-02, 12:18 AM
Just picking more nits:)

Radius of earth ~6371 kilometers
Height of ISS ~400 kilometers
Radius of ISS orbit ~6771 kilometers gravity at ISS orbit
g= G×m1/r2 = 6.6742×10-11 m3s-2kg-1 × 5.9736×1024 kg ÷ ((6.771×106 m)2 = 8.696 ms-2 which is not quite 9.8 ms-2

Just call it freefall (http://freefall.purrsia.com/) and be done with it. :)

Captain Kidd
2006-May-02, 12:47 AM
Ohh, that's a toughie. Either zero-G or the moon. After reading a book where they strapped on wings and flew around inside a big dome, I always wanted to try that. But zero-G would be really neat too.

Ah ha! In getting to the moon, you'll experience zero-G (freefall, whatever). I think I found my choice. ;)

Van Rijn
2006-May-02, 03:35 AM
Ah ha! In getting to the moon, you'll experience zero-G (freefall, whatever). I think I found my choice. ;)

I thought the same thing, though it is a bit of a cheat. Of course, it is possible to experience all three - for short periods - without using a rocket. From here: (http://www.msnbc.msn.com/id/5992077/)

A typical parabolic flight lasts about 90 minutes, with 15 up-and-down parabolas at an altitude of 24,000 to 34,000 feet. Two "Martian" arcs simulate one-third Earth gravity, three "lunar" arcs feel like one-sixth Earth gravity, and the final 10 provide the full zero-gravity experience.

Note that the Martian arcs last longer than the lunar arcs which in turn last longer than the "zero-gravity" arcs. (And Mars surface gravity is about .377, not .333... but I doubt you would notice that much difference.)

jkmccrann
2006-May-02, 10:39 AM
Probably not. ;)

I did not mean to insinuate that gravity acting upon a person in the ISS would be significant, just that it would not be zero. Small, yes. But not zero.

Just picking a nit, that's all. :)

Edited to add:

Actually I can give you the gravity acting on a person in the ISS. 9.8 m/s2. It is the precise velocity of the craft, acting in conjunction with Earth's gravity that give the illusion of 'zero gravity'. If, in fact, no gravity was acting on the ISS, it would sail off into space. Right?

Ok, good points all. I think it's all in the smilies sometimes! :)