A new analysis of Hubble data has clinched it: There’s too much light in the space around the Solar System.

Not much extra light, to be sure. Just a subtle, ghostly glow, a faint excess that can’t be accounted for in a census of all the light-emitting objects.

All the stars and galaxies surrounding the Solar System – and zodiacal light, aka dust on the Solar System’s plane – none of these can explain what astronomers are now calling “ghost light”.