Astronomy
The Contribution of Accreted Dwarf Galaxies to the Stellar Halo
Quick fact
Observations and simulations indicate that roughly 50% of the stars in the Milky Way's stellar halo were accreted from dwarf galaxies that were torn apart by gravity.
Why this is interesting
Look up at the night sky and you'll see the Milky Way, but half of the stars around the galactic center didn't start here—they were stolen from other galaxies. How did that happen?