Hubble is back, and seeing as clear as ever

Hubble’s “perfect 10” (Credit: NASA, ESA, and M. Livio)

By Jon Cartwright

After a month in “safety mode” following an error on its onboard data formatter, the Hubble is back online and taking photos again.

To evidence its good health, the grand old telescope has produced a “perfect 10” image of the galaxy pair Arp 147. According to a press release, the blue ring of the right galaxy formed its “0” shape when the left galaxy (the “1”) passed through. At the moment of impact a circular wave of dense material rippled through the right galaxy, colliding with material moving inwards from the galaxy’s gravitational pull. The resultant shockwaves and dense gas stimulated stars to form in a circle.