Russia launched its Soyuz 5 medium-lift rocket for the first time ever on Thursday (April 30), and things apparently went well.
For the past decade, astronomers thought they had a reasonable answer to that question. Around stars like our Sun, the two dominant planet types are sub-Neptunes, worlds resembling a shrunken Neptune, with thick gaseous envelopes and super-Earths, rocky planets up to ten times the mass of our own. Surveys had found them everywhere, orbiting star after star, and the assumption quietly took hold that these planets must be equally widespread across the Galaxy as a whole.

