They were snapped in pictures taken a month apart by the giant eye in the sky.
The new moons, which have not yet been named, are each thought to be less than 45 miles wide.
Pluto is so far away that it takes over 248 YEARS to go round the sun.
Nasa’s first space mission to the planet is due to launch in January.
Caption: The images, right, from Hubble show Pluto and Charon, the two brightest objects, on May 15 (above) and May 18 (below). The two fainter objects are the new moons. Credit: NASA.
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