On 24 April 1990, the space shuttle Discovery carried the Hubble Space Telescope into orbit. Thirty years later, thanks to multiple instrument upgrades, maintenance and repair missions, the orbiting observatory has become an international icon of science, beaming back a steady stream of unrivalled images that have made their way into every corner of modern life. The European Space Agency is marking the telescope’s 30th anniversary with a commemorative calendar featuring monthly “Hidden Gems” images that can be downloaded, printed or shared as desired. The 12 images were selected from 30 of Hubble’s lesser-known “gems” based on how many likes they received on ESA’s Facebook and Instagram pages.
The calendar’s January image is from a 2014 study called the Ultraviolet Coverage of the Hubble Deep Field, an 841-orbit exposure capturing some 10,000 galaxies.