Almost exactly one year after discovering dwarf planet Pluto's fourth moon - though not before actually naming poor little P4 - NASA announced Wednesday a fifth moon has been discovered orbiting the ex-planet.
Astronomers using the Hubble Space Telescope found the irregularly shaped moon, which they said measures 6 to 15 miles across. For now, it's being called P5.
"The moons form a series of neatly nested orbits, a bit like Russian dolls," said Mark Showalter of the SETI Institute in a statement released by the European Space Agency. Showalter is the leader of the scientific team that discovered the new moon.