Astronomers have discovered two of the youngest exoplanets ever found, the Los Angeles Times reports. The planets, each orbiting their own suns hundreds of light-years from Earth, are just a few million years old—babies next to our 4.6-billion-year-old solar system. Like the planets, the stars are also young: One of them, K2-33, has not yet developed into a full-sized “adult” star. That star’s planet, a gas giant called K2-33b, baffles scientists because it orbits so close to its star. Normally, gas giants form in the outer reaches of a solar system’s protoplanetary disk, so so-called “hot Jupiters” like the two new planets must have at some point in their history migrated inward. The findings, reported in two separate papers in Nature, could help scientists better understand how these “hot Jupiters” evolve.