# How Many G's On the Surface of the Sun?

• January 26th, 2014, 06:50 PM
lorbo
How Many G's On the Surface of the Sun?
G force is acceleration. Enough G force will kill you. Earth is 1 G, and we can handle that OK. But anything above that we can only handle for so long before we suffer or die.

Now, assuming a world had the mass of our sun,, how much G force would that be?

To find out all you really need is the G force of the sun.

I have a really good guess that human's couldn't surivive on such a world, even if they managed to land safely somehow on it.

Also, given the gravity of the surface of the sun (which would make something a 100 pounds on Earth weigh over 2000), it would be REALLY hard to escape it's pull if your on it's surface.

That's not even mentioning the heat. It's safe to say that any HUMAN led trip to the sun or a planet of equivalent mass is a one way trip.
• January 26th, 2014, 07:01 PM
Strange
Typing gravitational constant*mass of sun/(radius of sun)^2 into Google returns: 274.434141 m / s2 or almost exactly 28 times Earth gravity.
• January 26th, 2014, 07:16 PM
A more interesting topic would be, what if we found a near duplicate of Earth, the only difference is it is a 2G world. I think we would survive just fine. It would be hard living for the finders, but second and third generation humans would adapt just fine, I'm sure. Once they've adapted they could find a 3G world and adept from 2G to 3G and so on.
• January 26th, 2014, 07:23 PM
lorbo
Quote:

A more interesting topic would be, what if we found a near duplicate of Earth, the only difference is it is a 2G world. I think we would survive just fine. It would be hard living for the finders, but second and third generation humans would adapt just fine, I'm sure. Once they've adapted they could find a 3G world and adept from 2G to 3G and so on.

So hello superman huh?

Truth is, though, the superstrength wouldn't last once they come back to their homeworld (Earth).

Since muscles atrophy when in weaker gravity environments (just like with astrounauts), so it would be fun, while the strength lasted.

And that's presuming you have a way to get back to Earth in time where space ride itself doesn't weaken you muscles. But being able to handle more G's has advantages.

You could handle greater accelerations in your spaceships, cutting down travel times.
• January 26th, 2014, 07:39 PM
billvon
Quote:

A more interesting topic would be, what if we found a near duplicate of Earth, the only difference is it is a 2G world. I think we would survive just fine.

In a way. You'd initially see everyone get crippling arthritis by age 20, cardiovascular failure by age 30, varicose veins, lots of broken limbs etc. Eventually we'd evolve to better survive in the new environment, but such adaptations take tens of thousands of years. You don't get better knee cartilage just by being born in a high-G world, for example.

However there's a definite limit to how far this can go. Ants will never be able to be the size of elephants because their design just doesn't scale like that. Thus at some point we'd lose the ability to even evolve to better suit the higher G environment.
• January 26th, 2014, 07:42 PM
lorbo
Quote:

Originally Posted by billvon
Quote:

A more interesting topic would be, what if we found a near duplicate of Earth, the only difference is it is a 2G world. I think we would survive just fine.

In a way. You'd initially see everyone get crippling arthritis by age 20, cardiovascular failure by age 30, varicose veins, lots of broken limbs etc. Eventually we'd evolve to better survive in the new environment, but such adaptations take tens of thousands of years. You don't get better knee cartilage just by being born in a high-G world, for example.

However there's a definite limit to how far this can go. Ants will never be able to be the size of elephants because their design just doesn't scale like that. Thus at some point we'd lose the ability to even evolve to better suit the higher G environment.

Bilivion's right. We humans are hard wired to be, well, quite not so super.

Our superpower is our mind. And our machines, our glorious machines.

But on a high gravity world? Even those get wrecked LOL.
• January 26th, 2014, 07:46 PM
Quote:

Originally Posted by lorbo
Quote:

A more interesting topic would be, what if we found a near duplicate of Earth, the only difference is it is a 2G world. I think we would survive just fine. It would be hard living for the finders, but second and third generation humans would adapt just fine, I'm sure. Once they've adapted they could find a 3G world and adept from 2G to 3G and so on.

So hello superman huh?

Truth is, though, the superstrength wouldn't last once they come back to their homeworld (Earth).

Since muscles atrophy when in weaker gravity environments (just like with astrounauts), so it would be fun, while the strength lasted.

And that's presuming you have a way to get back to Earth in time where space ride itself doesn't weaken you muscles. But being able to handle more G's has advantages.

You could handle greater accelerations in your spaceships, cutting down travel times.

I was thinking they would make the 2G world their world and they wouldn't be moving back to Earth. But if you were raised on the new 2G world not only your muscles but your bones would be thicker and stronger. Also on a 2G world the atmosphere at the surface would most likely be denser and a much higher pressure that we would have to adjust to. Maybe we wouldn't even be very human looking anymore.
• January 26th, 2014, 07:58 PM
Quote:

Originally Posted by billvon
Quote:

A more interesting topic would be, what if we found a near duplicate of Earth, the only difference is it is a 2G world. I think we would survive just fine.

In a way. You'd initially see everyone get crippling arthritis by age 20, cardiovascular failure by age 30, varicose veins, lots of broken limbs etc. Eventually we'd evolve to better survive in the new environment, but such adaptations take tens of thousands of years. You don't get better knee cartilage just by being born in a high-G world, for example.

However there's a definite limit to how far this can go. Ants will never be able to be the size of elephants because their design just doesn't scale like that. Thus at some point we'd lose the ability to even evolve to better suit the higher G environment.

I did say that first generation would have some hard living. You have to remember even on Earth when humans were very primitive the average life span was something less than 30 years. Also, yes there would be some limit on G's that would be impossible to survive in no matter how adapted we were. Not sure what that would be not to much past 3 or 4 I'm sure.
• January 26th, 2014, 08:05 PM
grmpysmrf
Deleted for redundancy
• January 26th, 2014, 08:11 PM
pyoko
Yeah. And we just keep on going until we can stand on a neutron star drinking our beer.

Planets much smaller than Earth can and do have atmospheres denser than 1G Earth. The moon of Titan has a surface pressure of 146.7 KPa (compared to Earth's 101.3kPa).

edit: I changed my mind on what I posted and deleted half the post, so now my post seems irrelevant and is. Sorry.
• January 26th, 2014, 08:14 PM
billvon
Quote:

I was thinking they would make the 2G world their world and they wouldn't be moving back to Earth. But if you were raised on the new 2G world not only your muscles but your bones would be thicker and stronger.

But they would not be 2X stronger. We have a limit on how much we can adapt. And of course our joints would wear out sooner.
Quote:

Also on a 2G world the atmosphere at the surface would most likely be denser and a much higher pressure that we would have to adjust to. Maybe we wouldn't even be very human looking anymore.
After a few dozen generations we would start to look different. Probably much shorter and fatter, with thicker ankles/legs, less flexibility and more protection (fat? skin?) against impacts. And as usual, this would not be because we would adapt during our lifetimes somehow; it would be how evolution usually works, which is that all the tall/skinny/flexible people will die before reproducing,
• January 26th, 2014, 09:05 PM
Quote:

Originally Posted by billvon
Quote:

I was thinking they would make the 2G world their world and they wouldn't be moving back to Earth. But if you were raised on the new 2G world not only your muscles but your bones would be thicker and stronger.

But they would not be 2X stronger. We have a limit on how much we can adapt. And of course our joints would wear out sooner.
Quote:

Also on a 2G world the atmosphere at the surface would most likely be denser and a much higher pressure that we would have to adjust to. Maybe we wouldn't even be very human looking anymore.
After a few dozen generations we would start to look different. Probably much shorter and fatter, with thicker ankles/legs, less flexibility and more protection (fat? skin?) against impacts. And as usual, this would not be because we would adapt during our lifetimes somehow; it would be how evolution usually works, which is that all the tall/skinny/flexible people will die before reproducing,

So your saying the women will be ugly as sin?:mrgreen: Ouch! That will hurt reproduction as much as anything. (Just Kidding)

Beds would have to be closer to the ground as falling out of bed at 2G could be very bad for your health. Cities will have a much lower skyline, and considering what it takes to get off planet Earth. I would imagine it would be a great deal more difficult to achieve orbit on a 2G world.
• January 26th, 2014, 09:38 PM
Janus
[QUOTE=Bad Robot;519177] Also on a 2G world the atmosphere at the surface would most likely be denser and a much higher pressure that we would have to adjust to.

One thing to look out for here is that with a denser atmosphere, the air would have to have a lower percentage oxygen content. At partial pressures just 50% greater than Earth normal, Oxygen toxicity starts to be a problem.
• January 26th, 2014, 09:57 PM
Quote:

Originally Posted by Janus
Quote:

Also on a 2G world the atmosphere at the surface would most likely be denser and a much higher pressure that we would have to adjust to.

One thing to look out for here is that with a denser atmosphere, the air would have to have a lower percentage oxygen content. At partial pressures just 50% greater than Earth normal, Oxygen toxicity starts to be a problem.

Well yes that could be a problem. But after thinking about it, maybe the pressure wouldn't be so high. After all Venus has less than 1G but extremely high surface pressure, so I'm not sure the number of G's is relevant to atmospheric surface pressure.
• January 27th, 2014, 07:57 AM
John Galt
Quote:

Originally Posted by lorbo
I have a really good guess that human's couldn't surivive on such a world, even if they managed to land safely somehow on it........That's not even mentioning the heat.

When the American's were planning the moon landings a story circulated that the Irish were planning to land on the sun.
"You can't be serious", they were asked. "The sun is very hot. You would burn up."
"Ah, no sir, not at all." They replied. "We plan to go at night."
• January 27th, 2014, 09:10 AM
Ximlab
lol John

And on topic, I remember a kind of documentary from Hawking's idea, stating life on high G planets would get closer and closer to the ground, eventually with high enough Gs, every creature would be snake like.
Conversely on low G planet you can expect very tall/thin creature.
• January 27th, 2014, 10:31 AM
Quote:

Originally Posted by John Galt
Quote:

Originally Posted by lorbo
I have a really good guess that human's couldn't surivive on such a world, even if they managed to land safely somehow on it........That's not even mentioning the heat.

When the American's were planning the moon landings a story circulated that the Irish were planning to land on the sun.
"You can't be serious", they were asked. "The sun is very hot. You would burn up."
"Ah, no sir, not at all." They replied. "We plan to go at night."

The last time I read that one it was a blond joke.:mrgreen:
• January 27th, 2014, 11:44 AM
billvon
Quote:

Originally Posted by Ximlab
And on topic, I remember a kind of documentary from Hawking's idea, stating life on high G planets would get closer and closer to the ground, eventually with high enough Gs, every creature would be snake like.

If you want to take that to its logical extreme, check out Robert Forward's book "Dragon's Egg." It postulates what life would be like on a neutron star.
• January 28th, 2014, 03:08 AM
Karsus
Quote:

Originally Posted by billvon
If you want to take that to its logical extreme, check out Robert Forward's book "Dragon's Egg." It postulates what life would be like on a neutron star.

All the creatures would quickly be compressed by the extreme gravity until the electromagnetic forces maintaining their shape are overcome, resulting in incredibly thin, creature-shaped bumps of matter on the surface?