Now that's some serious hunger.

Ten billion years ago, our own Milky Way galaxy "cannibalized" a smaller nearby galaxy, according to a new study published Monday.

The violent collision didn't settle down for millions of years, the study authors said.

"It's a very gradual process – it's not something like a car crash," study lead author Carme Gallart of the Universidad de La Laguna in Spain told AFP. "It's very massive so it happens slowly in human terms, (but) not so slowly in cosmic time."

The merger provided the Milky Way with the material to create new stars and also gave it its current familiar appearance.

The smaller dwarf galaxy, the one that was "eaten," was named Gaia–Enceladus. It slowly formed the halo of our Milky Way.

According to Newsweek, this is not the only time the Milky Way has merged with other galaxies. It is thought that throughout its history, it has consumed many other, smaller galaxies.

And in a few billion years, it will merge with our big neighbor galaxy, Andromeda.

The research also provides an accurate dating of the age of the Milky Way’s stars. Knowing the exact ages of stars gives clues to which stars were present in the Milky Way before the merger and those that originated in Gaia-Enceladus.

“Identifying the oldest populations of stars that actually formed in the Milky Way is quite interesting, because they give us a kind of window into our galaxy's past,” Chris Hayes of the University of Virginia, who was not involved in the study, told National Geographic.

“These earliest populations of stars should exist, but now that they have been identified, they provide a powerful tool to piece together our galaxy's history."

The Milky Way includes about 100 billion stars, NASA said, including our sun. The sun formed "only" 4.5 billion years ago, much later than this cosmic collision between galaxies.

The study was published in the peer-reviewed British journal Nature Astronomy.