Beijing time:2022-10-09 12:32
[NTD, Beijing, October 9, 2022]Although people can’t see or hear, scientists say that the Milky Way, where our solar system is located, is like a stone thrown into it, causing ripples and rippling water. And this pebble is our nearest neighbor – the Sagittarius dwarf galaxy – which is the size of 400 million suns. The fluctuations that are now observable in the Milky Way are the result of these two galaxies colliding.
But don’t be nervous, the ripples won’t hurt you — in fact, according to a new study published Sept. 15 in the Monthly Notices of the Royal Astronomical Society, the ancient fluctuations could tell us a lot about the chaos of the Milky Way. history.
Importantly, the collision of the two galaxies occurred billions of years ago. Anything astronomers see now is the result of an ancient cosmic collision. But having said that, if we can’t actually see or feel the residual ripple, how would we know it’s there?
To examine the wobble of the universe, an international team of researchers used data from the European Space Agency’s Gaia space observatory to study the motion of more than 20 million Milky Way stars, tracking and comparing changes in their positions. Using knowledge and models from Galactic Seismology, they simulated the ripples and timing of the collision of the Sagittarius dwarf galaxies, arguing that the collision occurred hundreds of millions of years ago.
“We could see the stars bobbing and bobbing at different speeds,” co-author Paul McMillan, an astronomer at Sweden’s Lund University, explained in a statement.
As the Live Science website says, while previous research has known that the Milky Way we live in is indeed producing ripples, the latest study reveals for the first time that the impact of the impact was spread across the galaxy, with ripples extending all the way to the edge of the Milky Way. It also shows that our neighbor, the Sagittarius dwarf galaxy, was much larger at the time than it is now.
The study also confirmed a hypothesis that the Milky Way and the Sagittarius dwarf collided not once, but many times, throughout the evolutionary history of the universe. It provides a fascinating glimpse into the origins of the Milky Way and its neighbors; at the same time, studying galactic collisions in ancient times helps us understand possible future collisions.
(Transfer from The Epoch Times/Editor-in-charge: Ye Ping)
URL of this article: https://www.ntdtv.com/b5/2022/10/07/a103546368.html