MACS2129-1 compared with the Milky Way (artist’s impression)

This artist’s impression shows what the young, dead, disc galaxy MACS2129-1, right, would look like when compared with the Milky Way galaxy, left. Although three times as massive as the Milky Way, it is only half the size. MACS2129-1 is also spinning more than twice as fast as the Milky Way. The artist’s impressions shows regions within the Milky Way in blue from bursts of star formation, while the young, dead galaxy is yellow, signifying an older star population and no new star birth.