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View Full Version : Chances Our Solar System Would Survive?



Tinaa
2004-Jun-12, 07:02 PM
Check out the APOD (http://antwrp.gsfc.nasa.gov/apod/astropix.html) for today. If/when we collide with another big galaxy, will solar systems like ours survive? Or are solar systems so small that they may ride out the storm?

StarLab
2004-Jun-12, 09:18 PM
A Discovery Episode I'd seen came to this conclusion: if we are on one side of the galaxy during collision, our solar system would spin rapidly into the blackholes and the earth would blow up. On the other hand, if the solar system is on the other side of MilkyWay, our solar system would be flung out into space.

Spacemad
2004-Jun-12, 10:00 PM
The Milky Way galaxy is destined to collide with the Andromeda galaxy in some thousands of millions of years´ time - I don´t think our Solar System will be around at that time - it will have been consumed when Sol went nova millions of years before!

So we needed worry about what might happen to our Solar System when the Milky Way collides with Andromeda. :P

StarLab
2004-Jun-13, 04:58 AM
I'm sorry, but I'm not sure you got the facts straight, Spacemad. I'm sure the numbers are thus:
2 billion years: time to Andromeda-MilkyWay collision
5 billion years: time to final Sol supernova explosion

If my numbers are wrong, please correct me. ;)

galaxygirl
2004-Jun-13, 12:46 PM
The Milky Way isn't going to collide with the Andromeda galaxy for another 500 million years.

It's very unlikely that our solar system will collide with another star because there's so much space in the galaxies. But, there will be an increased number of stars in the newly merged galaxy which may lead to high zones of radiation. These zones will probably kill life off any planet within it.

antoniseb
2004-Jun-13, 03:56 PM
Originally posted by galaxygirl@Jun 13 2004, 12:46 PM
The Milky Way isn't going to collide with the Andromeda galaxy for another 500 million years.
StarLab's 2 billion years is closer to modern numbers.

You are right about the high radiation zones. There could also be a large increase in disturbances like comets coming to the inner solar system, or worse yet, if the Sun passes through Andromedan Oort clouds, those comets will impact planets with some large velocities.

On the plus side, I don't think that Andromeda is on a collision course with the center of the Milky Way. It is coming this way roughly, but I expect it's center will not get within 100,000 light years of Sag A*. The result will be a lot of star birth activity in the outer spiral arms. Our progeny should be fine.

GOURDHEAD
2004-Jun-14, 03:48 PM
Our progeny should be fine.

Especially if we scatter them around different parts of the galaxy. They may enter M31 whether they want to or not. Has anyone determined whether M31 and MW will orbit each other after the near collision?

Greg
2004-Jun-19, 05:52 AM
I havent seen a good simulation of any significant detail on the upcoming "collision." The newer numbers I am seeing are closer to 2 billion years. I am aware of older literature citing the 500 million year mark. Large galaxy interactions can be quite complicated and take hundreds of millions of years. Depending on how they approach each other, the galaxies can make a single pass and miss one another (not going to happen with this one,) make several passes and then capture each other and merge, or they can pass right through one another and then come around for several passes before merging into an elliptical galaxy. Most often when 2 large gravatationally bound glaxies get close to one another they will eventually merge.
If humanity survives long enough to witness this event, we will be scattered all over the galaxy by then. There probably will not be a single collision between a star from one galaxy into one in the other. There is a significant chance of near misses that would invoke a planet X like scenario of waves of comets sweeping towards the inner solar systems of inhabited solar systems. The SMBHs of both galaxies will eventually merge and both will probably generate polar outflows in a quasar like fashion until then. There will be a tremendous burst of starbirth in both galaxies.
The more interesting matter to me is that it is likely in my mind that a single humanoid race would dominate the Andromeda galaxy. If we are the only humanoid race in this one and live to dominate this galaxy, it could mean an intergalactic war of unimagineable proportions when the two galaxies meet. Just food for thought, but it might make for an interesting plot for a sci-fi book.

bossman20081
2004-Jun-19, 09:23 PM
well if current estimates are right, we wil have evolved into a different speceies by then. I dont think we would be affected because of the empty space in between objects in space.

StarLab
2004-Jun-20, 12:30 AM
I dunno about that...is two billion years time long enough to find a way to get our descendant's asses outta the galaxy?

GOURDHEAD
2004-Jun-20, 11:54 AM
is two billion years time long enough to find a way to get our descendant's asses outta the galaxy?

Yes, for quite a few. The collision will make it easy for us to get into M31 and it will be slow enough for us to dodge most of the disasters.