Pluto's Fifth

Astronomers preparing for the encounter of Pluto by the New Horizons probe in 2015 have discovered a fifth moon of the dwarf planet.  This one is irregularly shaped, and its orbit is well outside the other four.

Pluto is so small and so far away that learning much about it is difficult.  Even the Hubble, which was used to find this latest tiny moon, can only give hints of what might be there.  We will have to wait for New Horizons to arrive in the area to get solid, detailed information.