PARIS — A new study published in the journal Nature Astronomy using data from Gaia, a space observatory from the European Space Agency, shows the effects of the Sagittarius Dwarf Spheroidal Galaxy on the formation of the Milky Way Galaxy.
Due to gravitational forces, the Sagittarius dwarf galaxy crashes time and time again through the Milky Way's disc. One of these collisions occurred roughly at the same time as the formation of our Sun, around 4.7 billion years ago. It is possible this impact contributed to the Sun's creation.
The team of researchers examined luminosities, distances and colors of stars within 6,500 light-years around the Sun and then compared the information with already available stellar evolution models to understand the effects of the crashes.
Data from Gaia showed three periods of increased star formation. There were peaks 5.7 billion years ago, 1.9 billion years ago and 1 billion years ago. These periods coincide with times where the Sagittarius dwarf galaxy is believed to have crashed through the disc of the Milky Way.