When galaxies collide -- what happens to their magnetic fields? To help find out, NASA pointed SOFIA, its flying 747, at galactic neighbor Centaurus A to observe the emission of polarized dust -- which traces magnetic fields.

Now growing brighter, Comet Lulin is headed for its closest approach to planet Earth early next week. But the comet's greenish glow, familiar to earthbound skygazers, is replaced by false colors in this premier view from the orbiting Swift satellite.