Milky Way May Escape Fated Collision With Andromeda Galaxy (science.org) 33
sciencehabit shares a report from Science.org: For years, astronomers thought it was the Milky Way's destiny to collide with its near neighbor the Andromeda galaxy a few billion years from now. But a new simulation finds a 50% chance the impending crunch will end up a near-miss, at least for the next 10 billion years. It's been known that Andromeda is heading toward our home Galaxy since 1912, heading pretty much straight at the Milky Way at a speed of 110 kilometers per second. Such galaxy mergers, which can be seen in progress elsewhere in the universe, are spectacularly messy affairs. Although most stars survive unscathed, the galaxies' spiral structures are obliterated, sending streams of stars spinning off into space. After billions of years, the merged galaxies typically settle into a single elliptical galaxy: a giant featureless blob of stars. A study from 2008 suggested a Milky Way-Andromeda merger was inevitable within the next 5 billion years, and that in the process the Sun and Earth would get gravitationally grabbed by Andromeda for a time before ending up in the distant outer suburbs of the resulting elliptical, which the researchers dub "Milkomeda."
In the new simulation, researchers made use of the most recent and best estimates of the motion and mass of the four largest galaxies in the Local Group. They then plugged those into simulations developed by the Institute for Computational Cosmology at Durham University. First, they ran the simulation including just the Milky Way and Andromeda and found that they merged in slightly less than half of the cases -- lower odds than other recent estimates. When they included the effect of the Triangulum galaxy, the Local Group's third largest, the merger probability increased to about two-thirds. But with the inclusion of the Large Magellanic Cloud, a satellite galaxy of the Milky Way that is the fourth largest in the Local Group, those chances dropped back down to a coin flip. And if the cosmic smashup does happen, it won't be for about 8 billion years. "As it stands, proclamations of the impending demise of our Galaxy appear greatly exaggerated," the researchers write. Meanwhile, if the accelerating expansion of the universe continues unabated, all other galaxies will disappear beyond our cosmic event horizon, leaving Milkomeda as the sole occupant of the visible universe. The study is available as a preprint on arXiv.
In the new simulation, researchers made use of the most recent and best estimates of the motion and mass of the four largest galaxies in the Local Group. They then plugged those into simulations developed by the Institute for Computational Cosmology at Durham University. First, they ran the simulation including just the Milky Way and Andromeda and found that they merged in slightly less than half of the cases -- lower odds than other recent estimates. When they included the effect of the Triangulum galaxy, the Local Group's third largest, the merger probability increased to about two-thirds. But with the inclusion of the Large Magellanic Cloud, a satellite galaxy of the Milky Way that is the fourth largest in the Local Group, those chances dropped back down to a coin flip. And if the cosmic smashup does happen, it won't be for about 8 billion years. "As it stands, proclamations of the impending demise of our Galaxy appear greatly exaggerated," the researchers write. Meanwhile, if the accelerating expansion of the universe continues unabated, all other galaxies will disappear beyond our cosmic event horizon, leaving Milkomeda as the sole occupant of the visible universe. The study is available as a preprint on arXiv.
Whew! (Score:5, Funny)
I've gotta tell you guys, this is a big relief to me.
Re: (Score:2)
I've gotta tell you guys, this is a big relief to me.
Yeah, it'll be great to finally get a good night's sleep for once.
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I've gotta tell you guys, this is a big relief to me.
For you, yeah, but I had money riding on this.
"Impending"? (Score:5, Funny)
You keep using that word. I do not think it means what you think it means.
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It's coming right for us.
Quick, make yourself look big!
Re: "Impending"? (Score:2)
Predictions are hard. (Score:2)
Prediction is very difficult, especially about the future. (Probably of Danish origin, "Det er svært at spå, især om fremtiden." But with high probability not from Niels Bohr, albeit often attributed to him.)
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Prediction is not necessarily difficult or complicated - it depends very much on what you're trying to predict.
I will admit to some surprise that it turns out to be difficult to predict whether two masses the size of galaxies will collide or not. If I read the article correctly, in this case it's because previous predictions failed to include gravitational interactions with other galaxies in our local group, and the new answer is "it's going to be a close thing".
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Prediction is very difficult, especially about the future. (Probably of Danish origin, "Det er svært at spå, især om fremtiden." But with high probability not from Niels Bohr, albeit often attributed to him.)
Bohr was probably the best catcher the Yankees ever had.
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Also attributed to Yogi Berra.
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I've also seen it credited to Yogi Berra, an American baseball player famous for his self-contraditory statements.
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FWIW, I knew an astrologer who was trying to figure the effect Ceres would have on his charts. So whether you call it a planet, and asteroid, or a microphone, and astrologer may not care. (As they shouldn't.)
Also: Many astrologers are firm believers, who argue about the proper way to account for various bodies, and who use correct position calculations. I once taught one to program Bessel functions for some purpose or other. Later he became a professional programmer, segued into management and did quit
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But he kept believing in astrology.
Alas, there's no scientific study of astrology.
There's certainly a lot of opinions, among believers, on why and how it might work, and a lot of assertions, from non-believers, on why it absolutely cannot work, especially from Physicists who list all manners of reasons for why it's strictly impossible.
But actual studies on whether it works or not? None at all. At most, if that much, studies on how the Barnum Effect applies to people reading newspaper horoscopes, which is akin to criticizing chemistry on the
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Alas, there's no scientific study of astrology.
All you have to do is take some samples regarding something astrology predicts.
And it turns out, astrology is not shy about making predictions.
So what are you going on about.
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All you have to do is take some samples regarding something astrology predicts.
Doesn't work. Any anecdotal evidence in favor of astrological prediction is regarded by skeptics as a coincidence, while any failure is regarded as proof it's false. I could list everything it got right about me and others I know, and it'd be disregarded in that vein, or by presuming a strict inability of ours to avoid falling into BE.
I'll give one example form several. The astrologer looked at the chart of a person they didn't know and said that due to the combination of this with that, said person was lik
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FWIW, I looked into it (moderately) seriously at one point. Which meant casting charts and learning to interpret them.
Conclusion:
It is very good in explaining things that have happened, but lousy at predicting them ahead of time.
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It is very good in explaining things that have happened, but lousy at predicting them ahead of time.
Indeed. One suggestion I saw for this is that modernity has so much happening all at once that, different from the past, when things were much more regular, any kind of divination, which basically amounts to pinpoint the highest likelihood from among the set of potential outcomes, is now pointing at the one outcome that has, say, a 15% likelihood of happening, versus other three that have 13% each, four that have 10% each, and one that has 6%, whereas in the past the most likely outcome would have had a 90%
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(Ooops, mismoderated. Carry on...)
Poppcorn? (Score:4, Funny)
Where can I buy all the popcorn to watch that outcome?
Nice! (Score:4, Informative)
Couldn't we like nuke it (Score:3)
I've seen those asteroid movies, maybe we could just nuke the galaxy?
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What I want to know, is how do I get off this one before it's too late!
Where to watch? (Score:1)
Whether or not the collision occurs, there won't any humans or large life forms on Earth's surface in 5 billion years due to the Sun reaching the end of its time as a main sequence star.
If any humans exist in 5+ billion years (even if they don't look like us, if they are 'our' descendants they can still be called human), where should they go to watch the show?
Is there any reason to feel bad if/when a galaxy collision does happen?
Do galaxies feel bad when they merge with other galaxies?
Quick! (Score:2)
Guess we will have to wait (Score:2)
collision (Score:2)
This is pure collision collusion. This collision does not contain any actual collisions.
this isn't peer-reviewed yet... (Score:1)
I had ChatGPT analyze this post and determine if it adequately described how a study like this would be received within the larger scientific community. This was its response:
The Slashdot post titled "Milky Way May Escape Fated Collision With Andromeda Galaxy" briefly mentions the new research suggesting that the Milky Way might avoid colliding with Andromeda, a possibility previously thought unlikely. However, it does not adequately emphasize the preliminary nature of these findings or the fact that this h
It's a 3+-body problem (Score:1)