On the 23rd and 24th of January, 1930, a young astronomer working in Flagstaff, Arizona, scanned a small patch of the night sky. He was taking pictures of star positions, looking for anomalies that would signal movement somewhere at the edge of the solar system. He took the pictures then set them aside, not realizing…
It turns out there's no air up there: the distant dwarf planet Makemake is surprisingly lacking in an atmosphere, according to findings made by astronomers using telescopes at ESO's La Silla and Paranal observatories.
The Kuiper Belt, the vast asteroid belt of ice and rock that lies beyond Neptune, is home to three objects big enough to be considered dwarf planets: Haumea, Makemake, and our old friend Pluto. And now, we might have found three more.
Last week saw Neptune Day, the first anniversary - in Neptune years - of the planet's discovery on September 23, 1846. That got us thinking: what are the "birthdays" for all the other planets? Here's a handy, mildly insane guide.