In 1989, the Voyager 2 spacecraft was carrying out a survey of Neptune's moons and rings but inexplicably zipped by the planet without registering what would turn out to be truly big news. That finding would have to wait until earlier this month when Mark Showalter, an astronomer at the SETI Institute, was working with images sent back by the Hubble Space Telescope, when he discovered the presence of the smallest moon in the Neptunian system.
The moon, designated S/2004 N 1, is estimated to be no more than 12 miles across. That helps explain why Voyager 2 failed to notice its presence. NASA said the moon was about one hundred million times fainter than the faintest star you can see with the naked eye.… Read more