“Dupree and her colleagues suggested that as the star expanded in one of its
usual cycles, a portion of the surface accelerated much more rapidly, thanks to
a convection cell that had traveled from the interior of the star to its
surface. Those two events combined pushed out sufficient material far enough
from the star that it cooled down, forming stardust. That dust could account
for the dimming.”
“That left the much rarer Type Ia supernova as the strongest candidate, events
that generally occur once or twice each century in a given galaxy. These
supernovas are the source of most of the iron in the universe, and such an event
is the best match for the Hypatia stone’s unusual chemical makeup.”
posted 9/20/2022 8:00pm ∞
“This latest detection is a neutrino that began its journey in a faraway, as
yet-unnamed-galaxy in the constellation Delphinus, born from the death throes of
a shredded star.”
posted 3/28/2021 9:08pm ∞
“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 ∞