The galaxy NGC 691 in the constellation Aries presents a stunning target for the Hubble Space Telescope, showing off near perfect spiral arms wrapped tightly around a brilliant core. Discovered by William Herschel in November 1786, NGC 691 is about 120 million light years from the Milky Way and measures some 130,000 light years across. A type 1a supernova, a class used as “standard candles” in surveys supporting the discovery of dark energy, was detected in NGC 691 in 2005.
Hubble sees a distinctly disorganised dwarf galaxy
In this Hubble Space Telescope image we see an irregular dwarf galaxy known as UGC 4459, located in the constellation of Ursa Major (The Great Bear). While UGC 4459’s diffused and disorganised stellar population of several billion sounds impressive, this is small when compared to the 200 to 300 billion stars in the Milky Way.
Space telescopes find “twins” of Eta Carinae in other galaxies
Located about 7,500 light-years away in the southern constellation of Carina, Eta Carinae outshines our Sun by 5 million times. The binary system consists of two massive stars in a tight 5.5-year orbit, shrouded in an expanding veil of gas and dust from an enormous eruption seen in the 1840s. Now a study using archival data from NASA’s Spitzer and Hubble space telescopes has found five similar objects in other galaxies for the first time.