Astro Blog

https://www.sciencemag.org/news/2020/10/universe-teems-weird-black-holes-gravitational-wave-hunters-find Source:    By   Adrian Cho , Science Magazine.  Excerpt: Less than 5 years ago, physicists rocked the scientific world when they   first spotted gravitational waves —fleeting ripples in space and time—set off when two gargantuan black holes billions of light-years away swirled into each other. Since then, scientists have detected a scad of similar events,   mostly reported event by event . Today, however, researchers with a global network of gravitational wave detectors announced the first major statistical analyses of their data so far, 50 events in all. Posted online in four papers, the analyses show that black holes—ghostly ultraintense gravitational fields left behind when massive stars collapse—are both more common and stranger than expected. They also shed light on mysteries such as how such black holes pair up before merging....  

https://www.nytimes.com/2017/10/16/science/ligo-neutron-stars-collision.html Source:   By Dennis Overbye, The New York Times 2017-10-16. . . For GSS A Changing Cosmos chapter 9. Excerpt: Astronomers announced on Monday that they had seen and heard a pair of dead stars collide, giving them their first glimpse of the violent process by which most of the gold and silver in the universe was created. The collision, known as a kilonova, rattled the galaxy in which it happened 130 million light-years from here in the southern constellation of Hydra, and sent fireworks across the universe. On Aug. 17, the event set off sensors in space and on Earth, .... Such explosions, astronomers have long suspected, produced many of the heavier elements in the universe, including precious metals like gold, silver and uranium. ...a pair of neutron stars, the shrunken dense cores of stars that have exploded and died, collided at nearly the speed of light. These stars are masses as great as the sun pa...