Our planetary surveys are nowhere near Star Trek’s strike rate - they keep finding worlds stuffed with green-skinned females, humanoid societies, and thinly veiled metaphors for the situations they left behind a few hundred light (and regular) years ago. We find rocks which could freeze, explode and crush organic life just by looking at it. Now we’ve found a couple of Earth-sized oxygen atmosphered bodies, which would be all the way M-Class except for one thing: they’re stars.
Specifically, they’re “white dwarfs”: old stars who’ve burned all their hydrogen fuel, gone through the red giant stages where they fuse their way up to heavier elements, but lack the mass to supernova and collapse into neutron stars or black holes. This is actually what’ll happen to most stars, a relatively calm and cold fate, but there’s no explosion so you don’t hear about it much.
The stars were identified by scientists sifting through data from the Sloan Digital Sky Survey (SDSS), an eight year examination of the universe with a two point five meter telescope at Apache Point Observatory. Working at the University of Warwick and Kiel University, they identified stars with oxygen atmospheres at the very edge of the supernova-explosion mass limit. More massive stars can fuse heavier elements, and these stars had just enough mass to fuse all their carbon, exposing their oxygen-neon core, but not quite enough to collapse that core into explosion.
The stars are instead sustained by electron degeneracy pressure, where every atom just about elbows all the other atoms away, and will remain so until it’s eventually eaten by a black hole. Because you have to remember that everything eventually will be.
Luke McKinney
2 Earth-sized bodies with oxygen rich atmospheres http://www2.warwick.ac.uk/newsandevents/pressreleases/2_earth-sized_bodies/
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