(CNN) About 10 billion years ago, the Milky Way looked very different from the galaxy that now serves as a home to our solar system. In order to grow to its current massive size, the Milky Way probably consumed a dwarf galaxy in its younger days, according to a new study.

When the universe was in its infancy 13 billion years ago, stars were forming quickly, which led to the creation of the first dwarf galaxies. Dwarf galaxies contain between 100 million and several billion stars; the Milky Way now houses between 200 billion and 400 billion stars.

Dwarf galaxies merged in the early universe to form the larger galaxies that populate it today, including the Milky Way.

But decoding the timeline for the Milky Way has taken time. Now, using data from the Gaia space telescope, researchers can piece together the puzzle of the galaxy's past. A study including the data was published Monday in the journal Nature Astronomy

Researchers were able to use the space telescope to look back in time at the early stages of the Milky Way's formation, taking exact measurements of its stars to understand distance, brightness and position.

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