A favourite target for amateur astronomers, the Wild Duck Cluster, also known as Messier 11 and, more formally NGC 6705, is a stunning sight in even small telescopes with its brightest stars forming a “V” shape reminiscent of a flock of ducks. Located in the constellation Scutum, the cluster is about 6,200 light years from Earth and contains nearly 3,000 stars, making it one of the richest and most compact open clusters known. It was discovered in 1681 and included in comet-hunter Charles Messier’s famous catalogue in 1764. This view from the Hubble Space Telescope was chosen as “Picture of the Week” at the European Space Agency’s Hubble site.
Astronomers using data from the NASA/ESA Hubble Space Telescope and other observatories have performed an accurate census of the number of galaxies in the universe. The researchers came to the surprising conclusion that the observable universe contains at least two trillion galaxies. The results also help solve an ancient astronomical paradox — why is the sky dark at night?
Globular clusters offer some of the most spectacular sights in the night sky. These ornate spheres contain hundreds of thousands of stars, and reside in the outskirts of galaxies. The Milky Way contains over 150 such clusters — and the example shown in this NASA/ESA Hubble Space Telescope image, named NGC 362, is one of the most unusual ones.