# Some questions mostly dealing with large objects in space.

1. Jan 12, 2010

I have some questions I was hoping someone could help me with; any and all answers are greatly appreciated.
1) At what size and/or mass do most objects generate enough gravity to be spherical?
2) In high density areas (like in the Keiper belt or whatever) could an object exceed the mass necessary to be spherical but come under so many collisions that it’s in fact nowhere near spherical?
3) I know (or pretty sure I do) the shape of an object in space is effected by what that object is orbiting (such as Titan around Saturn) but if a planet size object were roaming (read: not in an orbit of any sort around any other object) is there a possibility it might not be spherical?
4) Every time I see a book describing space-time it shows a picture of a 3-d sphere sitting on a 2-d plane with the line of light curving along said plane; my question then is: would it be possible for light to bend not only within the little xy-plane shown but also along a z axis as well?
5) Is it possible with the billions of objects out in space for light to curve around for us to look out into the night sky and see earth from earth (assuming you had a high enough powered telescope)?
6) I’ve only ever heard of two theories regarding the fate of our universe, the big crunch and the big freeze, and from what I gather the big freeze has won out. But is it possible that everything in the universe is orbiting around the universe’s center of mass but we’re unable to see enough of the universe to make that out?
7) Is the shape of the universe a sphere? I’ve seen pictures of what the universe was supposed to look like in the billionths of a second after the big bang and they show it as an ellipsoid but is that still its shape now?
8) Following up on number 7, assuming the energy of the big bang were spread evenly, why is the early universe an ellipsoid and not a sphere, what propelled some stuff farther than other stuff?
In keeping with my trend of disclaimers: my background in physics consists solely of the science and history channel and the highest I’ve yet gone in math is multivariable calculus and linear algebra so if an equation is for some reason needed beyond that to fully convey an answer could you walk me there?
One other reasonably important thing of note, the last thread in which I asked a few questions was locked because it got off topic. Some of the off-topic stuff was interesting but none-the-less the administrators felt they had to step in. To avoid this thread meeting the same fate could that mostly be avoided? I’ll start a thread on the mathematical analysis of harmonics as it relates to the pleasure of experiencing music if necessary. :)

2. Jan 12, 2010

### pallidin

Wow. That's alot of questions!

I will say that for #5 the answer, to my understanding, is no.