Cleaning the four 8.2-metre mirrors used by the European Southern Observatory’s Very Large Telescope complex requires high technology and great care to keep the optical systems free of contamination or any other defects.
Massive middle age star clusters like NGC 339 resemble more common globulars, but they are much younger and it’s not yet known how they might be related. This remarkably detailed view comes from the Hubble Space Telescope.
Uranus’ small moon Miranda, as revealed by NASA’s Voyager 2 probe in 1986, is one of the strangest bodies in the solar system, with a unique patchwork appearance and cliffs towering 20 kilometres (12 miles) high.
The Spitzer Space Telescope, one of NASA’s original “Great Observatories,” is being retired after more than 16 years of infrared observations, but not before providing another look at the spectacular Tarantula Nebula.