The tiny new moon — announced July 20 and called P4 for now — brings the number of known Pluto satellites to four. And the find, made with the Hubble Space Telescope, suggests that NASA's New Horizons probe could make some big discoveries, too, when it makes a close flyby of Pluto in 2015, researchers said.
"The discovery of P4 just reinforces what we knew before: This is going to be completely new territory," said Hal Weaver, New Horizons project scientist at theJohns Hopkins University Applied Physics Laboratory in Laurel, Md. "We can't wait." [Pluto: A Dwarf Planet Oddity]