“[A] team of European researchers decided to model an event that should be
relatively uncommon: the two black holes didn’t start out in a mutual orbit but
happened to pass close enough to gravitationally latch onto each other. … The
models that produced a chirp that best matched the GW190521
signal saw a single pass that drew the black holes closer, followed by a single
rapid curve into the collision.”
posted 11/28/2022 8:00pm ∞
“Bubbles of hydrogen-ripping galaxy light began to grow, carving holes in the
cold, quiet bulk of the intergalactic gas. Over a billion years, the bubbles
filled the cosmos and nearly every hydrogen atom was torn in two, leaving
protons and electrons to wander the Universe separately again.”
Katie Mack ,
How the first stars split the Universe apart
(BBC Science Focus ,
October 10, 2022 )
posted 11/18/2022 8:00pm ∞
“Knowing that these two impacts generated events allowed for a direct comparison
between the estimates and the impact location. And it turns out the estimates
are quite good. One event was estimated at 3,530 ± 360 km away,
and it turned out to be 3,460 km from the lander, a difference of just
70 km.”
John Timmer ,
Big impacts picked up by seismograph on Mars
(Ars Technica ,
October 27, 2022 )
posted 11/12/2022 8:00pm ∞
“[I]n this case, the unseen companion was producing copious amounts of radiation
that was heating the star. This process essentially produces a star with a
‘daytime’ side bathed in radiation, so it’s more energetic and brighter, and a
‘nighttime’ side that emits the star’s intrinsic brightness.”
posted 9/16/2022 8:00pm ∞
“Cosmic strings appear to be a generic prediction of our (admittedly fuzzy)
understanding of the early Universe. We may not know exactly what went down all
those billions of years ago, but we’re fairly certain that it involved phase
transitions and that those phase transitions should support the existence of
topological defects like cosmic strings.”
posted 10/16/2022 8:00pm ∞