Type Ia supernovae are violent stellar explosions that shine as some of the brightest objects in the universe, but there are still many mysteries surrounding their origin. Now a team of astronomers have witnessed a supernova smashing into a nearby star, shocking it, and creating an ultraviolet glow that reveals the size of the companion.
Seeking to expand how we observe and understand phenomena such as supernovae and colliding black holes that generate gravitational waves, the National Science Foundation has just dedicated the Advanced Laser Gravitational Wave Observatories (Advanced LIGO) in Richland, Washington and Livingston, Louisiana.
Scientists from Rosetta’s OSIRIS team have discovered an extraordinary formation in the Aker region on the larger lobe of comet 67P/Churyumov-Gerasimenko. The largest of a group of three boulders with a diameter of approximately 30 metres appears to perch on the rim of a small depression. There seems to be only a very small contact area with the nucleus.
An international team of researchers have used the W. M. Keck Observatory to confirm the existence of the most diffuse class of galaxies known in the universe. These Ultra Diffuse Galaxies (UDGs) are nearly as wide as our own Milky Way galaxy — about 60,000 light-years — yet harbour only one percent as many stars.
Magnetars are dense, collapsed stars that possess enormously powerful magnetic fields. At a distance that could be as small as 0.3 light-years from the 4-million-solar mass black hole in the centre of our Milky Way galaxy, magnetar SGR 1745-2900 is by far the closest neutron star to a supermassive black hole ever discovered and is likely in its gravitational grip.
Hitting the jackpot is one thing, but if you hit the jackpot four times in a row you might wonder if the odds were somehow stacked in your favour. A group of astronomers led by Joseph Hennawi of the Max Planck Institute for Astronomy have found themselves in exactly this situation. They discovered the first known quasar quartet: four quasars, each one a rare object in its own right, in close physical proximity to each other.
Observations with ESO’s Very Large Telescope in Chile have discovered a new class of “dark” globular star clusters around the giant galaxy Centaurus A. These mysterious objects look similar to normal clusters, but contain much more mass and may either harbour unexpected amounts of dark matter, or contain massive black holes — neither of which was expected nor is understood.
Delta (δ) Cephei, prototype of Cepheids, which has given its name to all similar variable stars, was discovered 230 years ago by the English astronomer John Goodricke. The Cepheids role as distance calibrators for more than a century means δ Cephei is one of the most studied stars, but astronomers were shocked to discover that they lacked an essential piece of information…
© 2019 Pole Star Publications Limited