18+ min ago   (603+ words) The enormous Cygnus Bubble is usually linked to a busy star-forming region. A new study argues that the microquasar Cygnus X-3 may be the more natural source of its highest-energy gamma rays. Cygnus X-3 is a microquasar, a binary system containing a…...

1+ hour, 3+ min ago   (663+ words) The cosmic microwave background is the oldest light we can observe. Here is where it came from, what its tiny patterns reveal, and why it still matters. About 380,000 years after the Big Bang, the expanding universe had cooled enough for…...

23+ hour, 33+ min ago   (516+ words) An ancient star cluster is slowly coming apart in a galaxy 115 million light-years away. The thin trail it left behind is giving astronomers a new way to study dark matter beyond the Milky Way. Astronomers have identified the first stellar…...

2+ day, 19+ hour ago   (1153+ words) The objects are unusually soft in X-rays but bright in extreme ultraviolet light—exactly the combination that makes them difficult to find and potentially important to the history of stars and galaxies. A galaxy can be full of powerful objects…...

3+ day, 20+ hour ago   (556+ words) A brilliant X-ray source is not automatically a black hole. Matter falling toward a neutron star can also become intensely luminous, and some neutron stars have surprised astronomers by producing far more radiation than expected. Identifying the object requires evidence…...

6+ day, 1+ hour ago   (624+ words) A neutron star is what remains after the core of a massive star collapses. It is not a small ordinary star. It is the crushed core of a dead one, compressed until protons and electrons are forced together and most…...

1+ week, 4+ day ago   (373+ words) Researchers have completed one of the largest computer simulations of cosmic history yet assembled. Called ASTRID, it follows the growth of galaxies and black holes from the universe’s early days to the present, giving astronomers a virtual laboratory for testing…...

1+ week, 4+ day ago   (453+ words) Astronomers often treat the thin streams of stars around the Milky Way as sensitive tracers of dark matter. A new University of Washington simulation shows why that evidence needs to be read carefully: the visible structure of a galaxy can…...

1+ week, 4+ day ago   (447+ words) Two stars once considered promising Dyson sphere candidates have now been removed from the list. Follow-up observations with NASA’s James Webb Space Telescope showed that the infrared glow did not come from enormous artificial structures around the stars. It came…...

1+ week, 4+ day ago   (821+ words) A quasar is a distant galaxy with a brilliant active centre. Here is how a feeding supermassive black hole can outshine every star around it. What is a quasar? The short answer is a distant galaxy with an extraordinarily bright…...