Something Causes The Entire Milky Way Galaxy Is Rippling Like A Pond @TheCosmosNews

#thecosmosnews Imagine the Milky Way s 100 billion stars as a flat, tranquil pool of water. Now, picture someone dropping a stone the size of 400 million suns into that water. The tranquility is shattered. Wave after wave of energy ripples across the galaxy s surface, jostling and bouncing its stars in a chaotic dance that takes eons to calm. Astronomers suspect that something like this may have really happened — not just once, but several times over the past several billion years. In a new paper published Sept. 15 in the Monthly Notices of the Royal Astronomical Society, researchers explain how a nearby mini-galaxy — the Sagittarius dwarf galaxy — appears to have crashed through the Milky Way on at least two separate occasions, causing stars all around the galaxy to mysteriously oscillate at different speeds. Using data from the European Space Agency s Gaia space observatory, researchers compared the movements of more than 20 million stars located throughout the Milky Way, but particularly in the outer regions of the galaxy s disc. The data revealed a mysterious ripple, or vibration, that seemed to be jostling stars all throughout the galaxy. "We can see that these stars wobble and move up and down at different speeds," study author Paul McMillan, an astronomer at Lund University in Sweden, said in a translated statement.