Astro Blog

By Hannah Richter , Science.  Excerpt: “Dust is the building block of the universe,” says Melissa Shahbandeh, an astrophysicist at the Space Telescope Science Institute (STScI). Over millions of years, specks of cosmic dust and gas clump together to form large, dense clouds from which planets and stars are born. But the dust’s own origins have been mysterious. Now, in data from NASA’s JWST space observatory, Shahbandeh and her colleagues  have found a source for the dust that filled the early universe : giant stellar explosions called interacting supernovae, whose intense shockwaves can blast out dusty plumes that accumulated in the supernovae’s surroundings. These results, presented last week at the meeting of the American Astronomical Society and submitted to The Astrophysical Journal are “impressive,” says Lifan Wang, an astrophysicist at Texas A&M University who was not involved in the work. ...The findings...deepen understanding of where Earth and everything...

By PAUL VOOSEN , Science.  Excerpt: In its youth, the Solar System underwent a momentous upheaval: Gravitational tugs between the giant planets threw them off track, causing Jupiter’s orbit to jump closer to the Sun, while Saturn, Uranus, and Neptune were flung outward. The gravity of the rampaging giants scattered Pluto and other icy bodies to the Kuiper belt, shepherded the asteroid belt into its current location, and sent countless bodies crashing into the inner Solar System. For many years, researchers believed this “giant planet instability” occurred 600 million years after the Solar System’s birth 4.57 billion years ago, based on the ages of impact craters mapped on the Moon. Recently, evidence has mounted that it  occurred much earlier . And now, some researchers are homing in on a more precise date, just 60 million years after the Solar System’s formation, based on an analysis of rare meteorites derived from an ancient asteroid family, published today in Science. ...