A team of astronomers discovered a new, tiny and rapidly moving moon in orbit of Neptune, Sky and Telescope reported.
The moon had been unseen for more than a decade because of how small and quickly it moved around in orbit of Neptune. Mark Showalter and a team of observers noticed the moon after analyzing images of the planet taken from 2004-2009.
"This moon never sits still long enough to have its picture taken," Showalter, of the Search for Extraterrestrial Intelligence (SETI) institute, said.
On the first of July, Showalter said he was researching Neptune's faint arcs and rings. He said to make them stand out, he offset the Hubble sequence images to account for the rapid orbital movement.
"I was working with some older images from 2009 that I thought I was finished with," he said, adding that the moons orbited the planet in just hours.
Showalter found the "fairly obvious dot" in other telescope images from 2004 and 2005, but in images from a Voyager 2 mission 1989, he could not find the moon. The new moon's surface seemed dark to the observers and its diameter was estimated at no more than 10 to 12 miles, making it the smallest of Neptune's 14 known moons.
The newly discovered moon is believed to orbit between Neptune's Proteus and Larissa moons.
Showalter told BBC News his method for capturing the quick, tiny moon was similar to how a photographer would capture a moving object. He tracked the movement of the moon in more than 150 photographs.
"The moons and arcs orbit very quickly, so we had to devise a way to follow their motion in order to bring out the details of the system," Showalter said. "It's the same reason a sports photographer tracks a running athlete - the athlete stays in focus, but the background blurs."
