Hubble Discovers a Fifth Moon Orbiting Pluto

This image, taken by NASA's Hubble Space Telescope, shows five moons orbiting the distant, icy dwarf planet Pluto.

The green circle marks the newly discovered moon, designated P5, as photographed by Hubble's Wide Field Camera 3 on July 7.

Other observations that collectively show the moon's orbital motion were taken on June 26, 27, 29, and July 9, 2012.

The moon is estimated to be 6 to 15 miles across. It is in a 58,000-mile-diameter circular orbit around Pluto that is assumed to be co-planar with the other satellites in the system.

The observations will help scientists in their planning for the July 2015 flyby of Pluto by NASA's New Horizons spacecraft.

About the colours

This image was originally black and white and recorded only overall brightness. These brightness values were translated into a range of bluish hues. Such color "maps" can be useful in helping to distinguish subtly-varying brightness in an image. The colors in this image are not what human eyes would see looking at Pluto.

About the data

This image was created from HST data from proposal 12801 : H. Weaver (APL/JHU), M. Showalter (SETI Institute), S.A. Stern, M. Buie, W. Merline, and A. Steffl (Southwest Research Institute), H. Throop (Planetary Science Institute), and R. Soummer and M. Mutchler (STScI)