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It may be a long way off, but there's no doubt about it: our galaxyis heading for an epic mash-up with the neighbouring galaxyAndromeda. Thanks to the precise measurements that the Hubble Space Telescope 's deep views of space allow astronomers to make, they can now saywith certainty that the Milky Way will smash into the galaxy, whichis also known as M31, in about four billion years. "After nearly a century of speculation about the future destiny ofAndromeda and our Milky Way, we at last have a clear picture of howevents will unfold over the coming billions of years," said SangmoTony Sohn of the Space Telescope Science Institute in Baltimore ina press release issued by NASA and the institute on Thursday. Andromeda may still be 2.5 million light-years from the Milky Way,but the pull of gravity between the two galaxies and the darkmatter around them ensures that it will collide with our galaxy andeventually merge with it. That merging process will take another two billion years after thecollision, during which time stars will reorder themselves into neworbits around the fused galaxy's new galactic centre. Andromeda will be travelling about 400,000 kilometres per hour whenit hits our galaxy, but the collision won't harm Earth or our solarsystem since each galaxy's stars are far enough apart to avoidsmashing into each other. It will, however, knock the sun into anew part of the galaxy. "In the 'worst-case-scenario' simulation, M31 slams into the MilkyWay head-on, and the stars are all scattered into differentorbits," said Gurtina Besla of Columbia University in New York, whowas part of the team that studied the sideways motion of M31 todetermine whether it would, indeed, hit the Milky Way. "The stellar populations of both galaxies are jostled, and theMilky Way loses its flattened pancake shape with most of the starson nearly circular orbits. The galaxies' cores merge, and the starssettle into randomized orbits to create an elliptical-shapedgalaxy." Andromeda will also be travelling with a smaller galaxy, known asTriangulum, or M33, which might end up hitting the Milky Way firstand possibly also merge with the two larger galaxies. Astronomers had been trying to precisely measure M31's sidewaysmotion for more than a century and until now were not sure whethergalaxy would just nick the Milky Way, crash into it or avoid italtogether. By repeatedly observing select regions of Andromedaover a five- to seven-year period, they were able to nail down howthe two galaxies will interact. The recent findings will be reported in several papers in the Astrophysical Journal . I am an expert from magneticfloating.com, while we provides the quality product, such as China Magnetic Pop Display , China Floating Photo Frame, Magnetic Levitating Globe,and more.
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