A Closer Look at 'Rogue Planets' Adrift in the Universe

Not all stars are good parents to their budding planets — some get downright nasty and kick their children into interstellar space. We’ve found a handful of these free orphaned planets before, and they're called “rogue planets.” But a study today in Nature Astronomy suggests that the type we’ve seen so far, which are all gas giant sized, are the exception, not the norm.