# Has anyone thought about creatures would be on high gravity planets?

Discussion in 'Earth Science' started by dinokg, Jul 1, 2003.

1. ### dinokgRegistered Senior Member

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306
A creature on a planet with a thousand times earths gravity would have about a thousand times the strenghth of and earth creature and vice versa. Humans would have a thousand times there strength on a moon like Phobos. (It's one of Mar's two moons) Its has 1 thousandth the gravity of earth so it you can lift 100 pounds on earth you could lift 100,000 pounds on Phobos.

It would be like having super powers.

3. ### eburacum45Valued Senior Member

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1,297
Yes, well there are a few problems with living on high gravity planets- you would hardly be able to stand up for a start.

Maybe a 1.5g world would produce aliens built like weightlifters, who would be extravagantly strong if relocated to earth-

but any gravity greater than that would require a radical redesign, no doubt ruling out erect biped like humans.
A four-legged, six-legged or multiple-legged creature with legs like an elephant's, yet only a few feet tall-
these creatures would be very strong, certainly, but very alien to our eyes.
Used to a thick atmosphere they might even suffer decompression effects on our world-
possibly even rupture or explode;
although they would almost certainly not be oxygen breathers, as high gee worlds retain too much hydrogen for free oxygen to develop.

If you are talking about a thousand time's earths gravity- well, you are almost in the realms of the neutron star, here, and any inhabitant would probably be bizarre and a fraction of an inch tall.
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5. ### ZeroBannedBanned

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Their body's materials would be fundamentally different frmo ours.

Maybe they would develop very thick, rocky sort of coatings....like organic stone, almost?

7. ### VortexxSkull & Bones SpokesmanRegistered Senior Member

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2,242
Bird like creatures would be unlikely to develope, Water based floating fish would have a much better change in various gravity conditions.

Also, for landbased creatures, natures evolution would probably prefer creatures with a very high strength to bodyweight ratio, such as ANTlike creatures etc...

8. ### RedoubtableGuest

I would guess that the extreme gravity, and consequently super-dense matter, would preclude the emergence of sentient bipeds, or any mobile organism, for that matter.

Though I suppose the possibility of any life at all might be eliminated by these adverse conditions, I consider it probable that plant-life, or fungus, could subsist in preponderance in such a "heavy" environment.

9. ### ThomoRegistered Senior Member

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77
would a spherical shape be the best way to overcome extreme gravity? or a pyramid maybe

10. ### Fafnir665You just got served.Registered Senior Member

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1,979

Flat and spread out would probably be the least strained one.

11. ### ClockwoodYou Forgot PolandRegistered Senior Member

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4,467
Land critters with exoskeletons would have to shed their old carapaces underwater when they want to grow. They would otherwise have their unhardened shells crushed by their own weight.

12. ### RedoubtableGuest

I think primitive flora and fungoid parasites would be the most likely candidates.

13. ### SpecialistRegistered Senior Member

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46
After reading this thread and doing a little calculation it turns out that with a big enough planet, it's escape velocity will equal the speed of light if it has a radius and mass 72,00 times the size of earth's.

Of course before that happens it will collapse under it's own gravity.
Imagine if it could sustain it self, forming a livable environment on the surface. They would never be able to escape their planet

Code:
> # Rmv^2=2GMm
> # G=6.672*10^-11 N m^2 kg^-2
> # R=6378.137 km
> # v=c=3*10^8 km/s
> restart: Digits=100:
> c=sqrt(2*G*M/R);
G M
c = sqrt(2) sqrt(---)
R

> mr:=(5.976*10^24)/(6378.137):
> solve(c=sqrt(2*G*r),r); // assume escaple velocity is c, r is m/r ratio

2
c
1/2 ----
G

> 'mr'=0.5*(3*10^8)^2/(6.672*10^(-11)); // earth's mass to radius ratio

27
mr = .6744604317 10

> solve(x*mr=0.5*(3*10^8)^2/(6.672*10^(-11)),x);

719846.2239

10


14. ### Fafnir665You just got served.Registered Senior Member

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1,979
What if black holes are not as we understand them, and life lives on their infinitesimly small surfcae, what would their sky look like?

15. ### eburacum45Valued Senior Member

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1,297
The event horizon is only a one way barrier- you would still be able to see the universe in all directions, although the light would be strangely altered (blue shifted IIRC)
and distorted by the black hole's rotation (if any).

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16. ### spoilsportRegistered Senior Member

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90
Are you sure? One would think the increased air density would create enough buoyancy to cancel out increased gravity, but I may be wrong. Hey, that makes me think of something interesting though, some kind of floating "fish" that inhales and exhales to change it's density (thus the position in the air it floats at. That would be sweet.

17. ### river-windValued Senior Member

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2,671
maybe the things would switch over to a fluid-sac based movement system, instead of muscules. something similar to what spiders use. That would reduce the body weight while alowing for stronger power output.

18. ### dinokgRegistered Senior Member

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306
Hears something else that might happen on a high gravity planet.

The creatures might some how evolve a natural version of anti-gravity!

19. ### splunkyo' mama so fat...Registered Senior Member

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38
creatures here already have that. we call them "birds"

Last edited: Aug 3, 2003
20. ### dinokgRegistered Senior Member

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306
Birds don't use anti-gravity to fly they use their wings the make a strong enough air current for flight.

But what I'm talking about is a natural form of anti gravity. Even though it hasn't evolved on earth it could evolve elsewhere. Anyways animals like dolphins developed sonar way before people invented it so why not the same thing with anti-gravity?

21. ### splunkyo' mama so fat...Registered Senior Member

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38
lol true enough

but if the planet is REALLY 1000 times earth gravity, it seems a poor place to develop natural anti-grav abilities, if im thinkin of the same kinda anti-grav.

u mean like... hovercars? cuz im thinkin "morph" from Treasure Planet

22. ### dinokgRegistered Senior Member

Messages:
306
Hovering would probably be better than anti-gravity or regular flying. It would especially be good with a flat creature.

All it would need two do would have some type of propulsion system like regular breathing in and out air and it could move around rapidly!