Enlarge / The slightly hazy, light patch in the middle of the image is the DF2 galaxy, so diffuse that other galaxies are clearly visible behind it. (credit: NASA, ESA, and P. van Dokkum) The first evidence for dark matter were galaxies that behaved as if they had far more matter than could be accounted […]
Enlarge / Hubble Space Telescope mosaic image of the Crab Nebula, a six-light-year-wide expanding remnant associated with a star’s supernova explosion in 1054 CE (credit: NASA/ESA/J. Hester & A. Loll (Arizona State University) In August 1181, astronomers within China and Japan witnessed a bright “guest star” in the night sky that we now know to […]
Enlarge / A model of the supernova exploding inside a torus of gas ejected years earlier. (credit: Bill Saxton, NRAO/AUI/NSF) One of the stranger features of our Universe is the existence of what you might call dual-core stars. Many stars exist as part of a multistar system, and in some cases, their orbits are extremely […]
Enlarge / Astronomers continue to ponder the strange, dramatic dimming in the light from Betelgeuse, a bright red star in the Orion constellation, first observed in December 2019. (credit: ESO/M. Montargès et al. ) Back in June, we reported on a likely explanation for the strange, dramatic dimming of Betelgeuse , a bright red star […]
The successful gravitational-wave detections just keep coming for the LIGO-Virgo-KAGRA collaboration, which has now confirmed two separate “mixed” mergers between black holes and neutron stars, sending powerful gravitational waves rippling across spacetime. Those signals were detected last year by the collaboration, just 10 days apart. A year and a half later, the events officially constitute […]
Thanks to a new study conducted with ESO telescopes, we now know that Betelgeuse’s dip in brightness was the result of a “dusty veil” that formed from material that emerged from the star. Credit: ESO/L. Calçada. In December 2019, astronomers noticed a strange, dramatic dimming in the light from Betelgeuse, a bright red star in […]
Revisiting the aurora “dunes”: A time-lapse video recorded by a Scottish aurora borealis hobbyist Graeme Whipps was used to determine the speed of the phenomenon at over 200 m/s. Several years ago, amateur astronomers first spotted a rare type of aurora nicknamed “the dunes” because of its luminous, rolling wave patterns. Last year, astronomers proposed […]
Enlarge / A multi-wavelength image of the Cassiopeia A supernova remnant. (credit: Courtesy NASA/JPL-Caltech) Supernovae happen. We’ve witnessed enough of them that we’re pretty sure of that. Why they happen has been another issue entirely. As we’ve worked on understanding the physics that drives these immense explosions, we’ve occasionally gone through awkward periods when the […]
Two years ago, the Event Horizon Telescope (EHT) made headlines with its announcement of the first direct image of a black hole. Science magazine named the image its Breakthrough of the Year. Now the EHT collaboration is back with another groundbreaking result: a new image of the same black hole, this time showing how it […]
ASU astrophysicists Steven Desch and Alan P. Jackson set out to explain the odd features of ‘Oumuamua and have determined that it is likely a piece of a Pluto-like planet from another solar system. The mysterious pancake-shaped object dubbed ‘Oumuamua (Hawaiian for “messenger from afar arriving first”) generated considerable controversy earlier this year with the publication […]