Centauri Dreams
9 Apr 2021, 17:26 UTC
What governs the size of a newly forming star as it emerges from the molecular cloud around it? The answer depends upon the ability of gravity to overcome internal pressure within the cloud, and that in turn depends upon exceeding what is known as the Jeans Mass, whose value will vary with the density of the gas and its temperature. Exceed the Jeans mass and runaway contraction begins, forming a star whose own processes of fusion will arrest the contraction.
How Planetesimals Are Born
9 Apr 2021, 17:26 UTC
What governs the size of a newly forming star as it emerges from the molecular cloud around it? The answer depends upon the ability of gravity to overcome internal pressure within the cloud, and that in turn depends upon exceeding what is known as the Jeans Mass, whose value will vary with the density of the gas and its temperature. Exceed the Jeans mass and runaway contraction begins, forming a star whose own processes of fusion will arrest the contraction.
Nanowerk Space Exploration News
8 Apr 2021, 19:02 UTC
Astronomers at Western University have discovered the most rapidly rotating brown dwarfs known. They found three brown dwarfs that each complete a full rotation roughly once every hour. That rate is so extreme that if these "failed stars" rotated any faster, they could come close to tearing themselves apart. Identified by NASA's Spitzer Space Telescope, the brown dwarfs were then studied by ground-based telescopes including Gemini North, which confirmed their surprisingly speedy rotation.
Caught speeding: Clocking the fastest-spinning brown dwarfs (w/video)
8 Apr 2021, 19:02 UTC
Astronomers at Western University have discovered the most rapidly rotating brown dwarfs known. They found three brown dwarfs that each complete a full rotation roughly once every hour. That rate is so extreme that if these "failed stars" rotated any faster, they could come close to tearing themselves apart. Identified by NASA's Spitzer Space Telescope, the brown dwarfs were then studied by ground-based telescopes including Gemini North, which confirmed their surprisingly speedy rotation.
SPACE.com
7 Apr 2021, 18:29 UTC
Titanian methane droplets — and the sulfuric acid globules that fall on Venus and the liquid helium that makes up Jupiter's rain — are actually broadly similar to the raindrops that splash down here on Earth, a new study suggests.
Alien raindrops are similar to those on Earth
7 Apr 2021, 18:29 UTC
Titanian methane droplets — and the sulfuric acid globules that fall on Venus and the liquid helium that makes up Jupiter's rain — are actually broadly similar to the raindrops that splash down here on Earth, a new study suggests.
SciTech Daily
7 Apr 2021, 14:23 UTC
Inhabitants of our Milky Way galaxy living several billion years from now will have a markedly different-looking sky overhead. Two brilliant objects, each as bright as the full Moon or brighter, will drown out the stars with their radiance. These giant blazing light bulbs are a pair of quasars, brought to life by the collision of our Milky Way with the neighboring Andromeda galaxy.
“Death Star” Dueling Quasars Looming in the Sky: Hubble Spots Double Quasars in Merging Galaxies
7 Apr 2021, 14:23 UTC
Inhabitants of our Milky Way galaxy living several billion years from now will have a markedly different-looking sky overhead. Two brilliant objects, each as bright as the full Moon or brighter, will drown out the stars with their radiance. These giant blazing light bulbs are a pair of quasars, brought to life by the collision of our Milky Way with the neighboring Andromeda galaxy.
Starts With a Bang!
7 Apr 2021, 14:01 UTC
Enough mass in one location will always create a black hole. But not all masses are possible.
Some Black Holes Are Impossible In Our Universe
7 Apr 2021, 14:01 UTC
Enough mass in one location will always create a black hole. But not all masses are possible.
astrobites
7 Apr 2021, 11:00 UTC
The Milky Way Galaxy is our home, and yet we don’t have a very clear picture of how it is structured. We know that we live inside a barred spiral galaxy, but how many spiral arms does our Galaxy have? Where are they located? How tightly are they wound?
Four Spiral Arms Walk into a Bar…
7 Apr 2021, 11:00 UTC
The Milky Way Galaxy is our home, and yet we don’t have a very clear picture of how it is structured. We know that we live inside a barred spiral galaxy, but how many spiral arms does our Galaxy have? Where are they located? How tightly are they wound?
Centauri Dreams
6 Apr 2021, 19:45 UTC
Let’s take a look at how Earth’s carbon came to be here, through the medium of two new papers. This is a process most scientists have assumed involved molecules in the original solar nebula that wound up on our world through accretion as the gases cooled and the carbon molecules precipitated. But the first of the papers (both by the same team, though with different lead authors) points out that gas molecules carrying carbon won’t do the trick. When carbon vaporizes, it does not condense back into a solid, and that calls for some explanation.
Explaining Earth’s Carbon: Enter the ‘Soot Line’
6 Apr 2021, 19:45 UTC
Let’s take a look at how Earth’s carbon came to be here, through the medium of two new papers. This is a process most scientists have assumed involved molecules in the original solar nebula that wound up on our world through accretion as the gases cooled and the carbon molecules precipitated. But the first of the papers (both by the same team, though with different lead authors) points out that gas molecules carrying carbon won’t do the trick. When carbon vaporizes, it does not condense back into a solid, and that calls for some explanation.
SPACE.com
6 Apr 2021, 15:00 UTC
When humans build the first bases and habitats on other worlds, they'll confront dangers and challenges unlike any faced by the astronauts who went before them. To prepare for such challenges, scientists are descending deep underground into lava tubes in Hawaii that simulate conditions on rocky alien worlds.