New calculations suggest Andromeda might not collide with Milky Way
The uncertainty of science: Scientists using new data from the Hubble Space Telescope as well as Europe’s Gaia space telescope, combined with many computer models, have determined that the 2012 prediction that the Andromeda galaxy would collide with Milky Way in five billion years was much more uncertain. From the abstract of the paper:
[W]e consider the latest and most accurate observations by the Gaia and Hubble space telescopes, along with recent consensus mass estimates, to derive possible future scenarios and identify the main sources of uncertainty in the evolution of the Local Group over the next 10 billion years. We found that the next most massive Local Group member galaxies — namely, M33 and the Large Magellanic Cloud—distinctly and radically affect the Milky Way — Andromeda orbit. Although including M33 increases the merger probability, the orbit of the Large Magellanic Cloud runs perpendicular to the Milky Way–Andromeda orbit and makes their merger less probable.
In the full system, we found that uncertainties in the present positions, motions and masses of all galaxies leave room for drastically different outcomes and a probability of close to 50% that there will be no Milky Way–Andromeda merger during the next 10 billion years. Based on the best available data, the fate of our Galaxy is still completely open.
The press release at the first link above makes it sounds as the previous prediction of a collision had been fully accepted as certain by the entire astronomical community, and that is balder-dash. It was simply the best guess at the time, highly uncertain. This new prediction — that we really don’t know what will happen based on the data available — is simply the newest best guess.
This new analysis however is certainly more robust and honest.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The uncertainty of science: Scientists using new data from the Hubble Space Telescope as well as Europe’s Gaia space telescope, combined with many computer models, have determined that the 2012 prediction that the Andromeda galaxy would collide with Milky Way in five billion years was much more uncertain. From the abstract of the paper:
[W]e consider the latest and most accurate observations by the Gaia and Hubble space telescopes, along with recent consensus mass estimates, to derive possible future scenarios and identify the main sources of uncertainty in the evolution of the Local Group over the next 10 billion years. We found that the next most massive Local Group member galaxies — namely, M33 and the Large Magellanic Cloud—distinctly and radically affect the Milky Way — Andromeda orbit. Although including M33 increases the merger probability, the orbit of the Large Magellanic Cloud runs perpendicular to the Milky Way–Andromeda orbit and makes their merger less probable.
In the full system, we found that uncertainties in the present positions, motions and masses of all galaxies leave room for drastically different outcomes and a probability of close to 50% that there will be no Milky Way–Andromeda merger during the next 10 billion years. Based on the best available data, the fate of our Galaxy is still completely open.
The press release at the first link above makes it sounds as the previous prediction of a collision had been fully accepted as certain by the entire astronomical community, and that is balder-dash. It was simply the best guess at the time, highly uncertain. This new prediction — that we really don’t know what will happen based on the data available — is simply the newest best guess.
This new analysis however is certainly more robust and honest.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Apparently that expedition from the Culture might have to alter course a bit. Hopefully someone will get the reference.
But I thought the Science was settled. WTF? ……..
OTOH, because it is science (no caps required), by definition, it is never settled. Best of all, we will have a lot of time to figure out how the collision may or may not progress while watching same. Cheers –
Dodged that bullet. 😅
I’m going to immediately write Allstate and demand a reduction in premiums on my galactic collision policy. :)