The Milky Way is 'rippling' like a pond, and scientists may finally know why

Imagine the stars as a pool of water. Imagine a person dropping a stone the size of 400 million suns into that water The peace is broken. In a chaotic dance that takes millions of years to calm, wave after wave of energy ripples across the galaxy's surface.

Astronomers think that something like this has happened several times over the past billion years.

In a new paper published in the Monthly Notices of the Royal Astronomical Society, researchers explain how a nearby mini-galaxy appears to have crashed through the Milky Way on at least two separate occasions.

In the new tab, there is a story about the largest galaxy ever found.

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. The data showed that there was a vibrating star all around the galaxy.

The author of the study said that they could see that the stars were moving at different speeds.

The team was able to model a wave pattern that could explain the strange ripples in the stars. It was concluded that the ripples were released hundreds of millions of years ago when the Sagittarius dwarf galaxy last passed through our galaxy. The researchers said it was likely that a second collision had taken place.

This new research is the first to show that the ripples from an ancient collision with Sagittarius extended all the way to the edge of the galaxy's disk. The researchers wrote that the new research should help them piece together the long and violent history of our universe.

The Sagittarius dwarf galaxy is 400 times the mass of Earth's sun and the Milky Way's mass is 1.5 trillion suns. Scientists think that Sagittarius lost up to 20% of its mass to our galaxy after repeated crashes over the past billion years.

The shape and size of our galaxy may have changed as a result of these collisions, according to a study. Baby booms of new stars in the Milky Way were caused by the crashes between our galaxy and Sagittarius, according to a new study.

It was originally published on Live Science