Well, actually, many stars from both of the galaxies will be flung far away, and those may well become excellent places to live. Anyway, check out some of the videos here:arjan de lumens said:
http://www.cita.utoronto.ca/~dubinski/nbody/
Milky Way to collide with Andromeda Galaxy
- Thread starter Deepak
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http://www.cita.utoronto.ca/~dubinski/nbody/
The odds for stars colliding are very small, even with star densities 10x higher than in our part of the galaxy.
There the average distance between stars is around 2 light years. Compare that distance to the size of the sun:
Sun: ~1,400,000km i diameter
2 LY: 86400s/day*365day/y*2y*300,000km/s= 18,921,600,000,000km
For comparison reduce the Sun to the size of a pinhead (1mm) and each star would be 140meters apart.
The Universe consists of mostly nothing.
Cheers
Gubbi
There the average distance between stars is around 2 light years. Compare that distance to the size of the sun:
Sun: ~1,400,000km i diameter
2 LY: 86400s/day*365day/y*2y*300,000km/s= 18,921,600,000,000km
For comparison reduce the Sun to the size of a pinhead (1mm) and each star would be 140meters apart.
The Universe consists of mostly nothing.
Cheers
Gubbi
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That possibly might not happen; the size of planetary orbits increase over time due to the Sun losing mass (more details) and there is likely to be an increased rate in mass loss during the helium phase (in addition to this, stars also fluctuate in size during the build-up to the red giant phase). Mind you, even if the Earth isn't enveloped by the Sun's outer layers, we'll certainly be in the corona!Chalnoth said:
If the galaxies pass through each other and go about their merry ways, I conjured up in my astronomy class that if we colonized a bunch of stars in Andromeda and after everything passes through, we would be a civilization that would have colonized a different galaxy!
My professor thought it was interesting only if we ever get around to getting off this rock in the first place. He made a point that ever since we landed on the moon we pretty much became more focused on the planet and our capabilities in space have diminished, that it would take considerable effort to even to go back to the moon with manned missions.
Good point about earth being gone before that happens, even though the sun will Red Giant in a 4-5 billion years, it's going to be well before that when this planet becomes inhospitable because the sun will steadily get more luminous and larger so increasing the planet's temperatures over time. Global Warming would be the least of our problems. I think it's like a billion years or so we can still live on Earth before it becomes unsustainable or we have to move underground or as I read somewhere, figure a way to move the earth's orbit farther away.
My professor thought it was interesting only if we ever get around to getting off this rock in the first place. He made a point that ever since we landed on the moon we pretty much became more focused on the planet and our capabilities in space have diminished, that it would take considerable effort to even to go back to the moon with manned missions.
Good point about earth being gone before that happens, even though the sun will Red Giant in a 4-5 billion years, it's going to be well before that when this planet becomes inhospitable because the sun will steadily get more luminous and larger so increasing the planet's temperatures over time. Global Warming would be the least of our problems. I think it's like a billion years or so we can still live on Earth before it becomes unsustainable or we have to move underground or as I read somewhere, figure a way to move the earth's orbit farther away.
K.I.L.E.R said:
Yeah, I think Bush picked up the wrong fight
Kanyamagufa
Regular
Don't forget you're sunglasses.
arjan de lumens
Veteran
Gamma ray bursts aren't THAT powerful unless they are within a few light years away. What is believed to happen in case of a nearby GRB (few hundred to a few thousand light years) is mainly that the ozone layer will be destroyed over the exposed half of the planet. Such an event would probably render large areas uninhabitable and un-arable due to UV radiation for several years, killing most but not all of Earth's human population through massive crop failures and general ecosystem collapse.ANova said:
If this were true, Then the Galaxies according to evolutionary timelines would have already collided at least twice.
If Andromeda will pass 2 more times in 10 billion years then the collision would have happened already.
Which means?
Its never happened before. Because the earth and the universe are not billions of years old. It only looks that way because it was formed instantly and completely mature. There are dozens upon dozens of these kind of phenomenon out there that scientists are not being honest about. Because if you actually look at them all and what they indicate they cannot accept the implications.
Not necessarily, Boltneck -- pass != collide. It seems the galaxies have passed by, getting closer each time, and they'll likely be close enough to actually "collide" the next time or the one after and coalesce into one (where as previous passes haven't been close enough to cause them to join together).
Conspiracy theories aside, I don't think all the astronomers in the world are lying to themselves and everyone else because they don't want to believe in "God" -- many scientists/physicists/astonomers/etc are very much of the religious sort because nobody knows what started the "big bang" still (or what was before it).
Edit: astronomers, not astrologists - thanks, arjan.
Conspiracy theories aside, I don't think all the astronomers in the world are lying to themselves and everyone else because they don't want to believe in "God" -- many scientists/physicists/astonomers/etc are very much of the religious sort because nobody knows what started the "big bang" still (or what was before it).
Edit: astronomers, not astrologists - thanks, arjan.
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arjan de lumens
Veteran
AFAICS, this doesn't make sense at all. Galaxy collisions aren't clockwork periodic events any more than e.g. comings of Christ are. It's a bit like saying that if Jesus returns 10 years from now, then he MUST have returned 200 times in the timespan from his first appearance ~2000 years ago until today.boltneck said:
arjan de lumens
Veteran
Hmmm, better not confuse "astrologists" with "astronomers" - I suspect both groups would be rather offended by being associated with the other one.Bobbler said:
Not sure what to say about the religious aspects of Big Bang - it appears as an event that we have no way of seeing past, vaguely similar to the way an ordinary Christian, unable to peer into God's mind, would assert "God works in mysterious ways" (although with the major difference that the astronomer usually has much less of a personal relationship with big-bang than the Christian has with God)
To some extent. In the imprint of the cosmic microwave background, left at about 300,000 years after the "start" we can see the signatures of what was before.arjan de lumens said:
Cosmic neutrinos decoupled at about 1 second after the "start" and as such are an even better probe of early physics.
Gravity waves decoupled even earlier, and may give significant information about inflation, released in a tiny fraction of a second after the "start" of it all.
(note: I put "start" in quotes every time, because I place this in the context of zero time as measured by the standard big bang: it is fundamentally possible for inflation to have lasted much longer, some postulate infinitely long)
Currently, though, the best indication of early physics is Big Bang Nucleosynthesis. Big Bang Nucleosynthesis is the application of known nuclear physics to the very early universe to predict the abundances of elements before any stars formed. This prediction is measured by looking at old star populations. It turns out that the calculated abundances of Hydrogen, Deuterium, and Helium all agree with experiment to an excellent degree of accuracy. But, for some reason we do not yet know, Lithium is way off.
Blue giants go hypernova after a black hole forms in the center. This results in all the energy of the star compacting at such a rate that it manages to escape the black hole, think about that. The shockwave is so powerful that it is catagorized as the largest explosion in the known universe right behind the big bang. It literally destroys whole galaxies; astronomers call these Death Stars. A simulation has been created of what would happen to Earth if the closest star to this galaxy went hypernova, and although it wouldn't destory the planet, rest assured nothing would survive.arjan de lumens said:
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