Four Teenage Planets Around a Young Star
350 light-years away, four planets orbit the star V1298 Tau. They are 5–10 times larger than Earth but lighter than they appear. For nine years, astronomers tracked their motion to understand what they are made of and how they lived in the past.
The planets are lined up in a chain: their orbital periods are nearly in 3:2, 2:1, and 3:1 ratios.