NASA’s Hubble Space Telescope captured the rare occurrence of the three largest moons of Jupiter namely Europa, Callisto, and Io racing across the banded face of the gas-giant planet. This was a rare occurrence, as the event occurs once or twice in a decade.
NASA gave this information on 5 February 2015.
The moons in the photos captured by the camera have distinctive colours. The ancient cratered surface of of Callisto is brownish; the smooth icy surface of Europa is yellow-white; and the volcanic, sulfur-dioxide surface of Io is orange.
The Hubble images were captured by Hubble’s Wide Field Camera 3 in visible light on 24 January 2015.
These so-called three Galilean moons complete orbits around Jupiter with durations ranging from 2 days to 17 days. They were named after the 17th century scientist Galileo Galilei, who discovered four large moons, namely Io, Europa, Ganymede and Callisto with a telescope. Jupiter has over 60 moons.
About Hubble Space Telescope
Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. The telescope is managed by NASA's Goddard Space Flight Center in Greenbelt, Maryland, while the Hubble science operations are conducted by the Space Telescope Science Institute (STScI) in Baltimore.