Long streamers of gas glow in the Large Magellanic cloud, remnants of a supernova blast that destroyed a white dwarf in a Type 1a supernova. Its remnants are known as SNR 0454-67.2. Such explosions occur when a white dwarf sucks in enough material from a companion star to reach a critical mass, triggering a catastrophic core collapse, rebound and shock wave that blows the star apart. Its remnants are blasted into the surrounding space, including heavy elements that were cooked up in the detonation. Because Type 1a supernovas all occur in the same fashion, they shine with a known brightness, or luminosity, that can be used to determine their distance. Such supernovae are known as “standard candles” and they are critical to modern cosmology, helping astronomers measure changes in the acceleration of the universe’s expansion due to dark energy.
Astronomers using the unique ultraviolet capabilities of the NASA/ESA Hubble Space Telescope have identified nine monster stars with masses over 100 times the mass of the Sun in the star cluster R136, located in the Tarantula Nebula within the Large Magellanic Cloud. This makes it the largest sample of very massive stars identified to date.
Astronomers using the Atacama Large Millimetre/submillimetre Array (ALMA) have discovered a tsunami of stars and gas that is crashing midway through the disc of a spiral galaxy known as IC 2163. This colossal wave of material — which was triggered when IC 2163 recently sideswiped another spiral galaxy dubbed NGC 2207 — produced dazzling arcs of intense star formation that resemble a pair of eyelids.
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.