“[T]he earliest image indicates that it was roughly 100,000 Kelvin, which
suggests we were looking at it just six hours after it exploded. The latest
lensed image shows that the debris had already cooled to 10,000 K over the
eight days between the two different images.”
posted 11/24/2022 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 ∞
“Matching the density of the two planets produces a model that has a bit over
10 percent of the planet’s mass composed of water. This, however, means
that about half the planet’s volume is water. … Due to the planet’s mass, the
pressure of the atmosphere would be immense and could create a layer of
supercritical water between the atmosphere and the ocean.”
posted 12/20/2022 8:00pm ∞
“[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 ∞