Steven Majewski, a professor in the College’s Department of Astronomy, added: “This allows us to explore how stars of different age participate in the warp and lets us zero in on when it was created.
“Knowing this, then, gives us an idea of why it was created.”
The astronomers found the Milky Way’s warp was most likely caused by the flyby of a nearby galaxy, called the Sagittarius Dwarf Spheroidal Galaxy.
According to the study, the galaxy passed the Milky Way about three billion years ago.
And the warp is likely the byproduct of the galaxy tugging on the Milky Way with its gravity.
source: express.co.uk