Astronomers didn't expect so many quasars to have halos. The discovery may help them probe the large-scale structure of the universe, aka the cosmic web.
Orion the Hunter - one of the most familiar constellations to many because of its prominent Belt of 3 stars - is coming back into view in the evening sky.
The Arctic's multi-year sea ice - ice that survives the summer melt - is weaker and there's less of it. Satellite images show the difference between 1984 and now.
The long-lasting 2016 Taurid meteor shower hasn't been as spectacular as last year's shower. But, like all Taurid showers, it has produced some fireballs!
Note the moon's position relative to Mars across these 2 evenings. Its eastward motion on our sky's dome is due to its eastward motion in orbit around Earth.