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Every Snowflake Needs a Speck of Dust and So Do Planets

A snowflake cannot form out of nothing. Water vapour will sit in the air quite happily, supercooled and reluctant, until it finds a speck of dust to build on and then it crystallises around it. Cosmochemists have had a version of that problem for decades. The early Solar System was a furnace of gas, and the first solid grains had to condense out of it somehow, yet condensing from a perfectly uniform gas is slow and difficult work. New research from Caltech, analysing fragments of a meteorite that fell over Mexico in 1969, suggests the seeds were already there. Buried inside the oldest solids we possess are specks of stardust from a star that lived and died before the Sun existed. from Universe Today https://ift.tt/WCxv6sj via IFTTT
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The Dark Matter Detector in the Scottish Borders

Hunting for dark matter usually means building something enormous and burying it — a tank of liquid xenon in a mine, a magnet the size of a lorry, decades of engineering and a great deal of money. A team in Japan have just done it differently. They realised that the Earth's own magnetic field is larger than any magnet we could ever construct, and that the gap between the ground and the ionosphere behaves as a natural resonating cavity, ringing at around eight cycles per second. If dark matter is what some theorists suspect, it should leave a faint hum in that cavity. So they went looking, not with a new instrument, but in ten years of geomagnetic readings already recorded at a quiet observatory in Dumfriesshire in Scotland. from Universe Today https://ift.tt/BrJ2DgV via IFTTT

What If There's a Star Inside a Black Hole?

Ask what lies inside a black hole and the honest answer has always been a bit of a shrug and something about a singularity, a point where density becomes infinite and physics stops being able to tell you anything at all. It is the most unsatisfying answer in astrophysics, second only perhaps to what happened before the Big Bang. Now two theorists in China have produced a solution in which something else sits inside the horizon entirely, a neutron star, whole and intact, twelve kilometres across, its interior perfectly well behaved and apparently defying the laws of physics. from Universe Today https://ift.tt/HkjDALS via IFTTT

Watching the First Moments in a Star's Death

Astronomers were fortunate when the Einstein Probe detected the difficult-to-observe initial shock break out (SBO) from a supernova. The SBO is the first electromagnetic indication that a star is going to explode, and by observing it and the aftermath, researchers were able to determine what type of progenitor star exploded, and what it's pre-explosion environment was like. from Universe Today https://ift.tt/g25DbIl via IFTTT

Seven Needles, 800,000 Haystacks

A quasar is a supermassive black hole in the act of feeding, and it’s so bright that it drowns out the galaxy it sits in. That is a nuisance if you want to weigh the galaxy and weighing it is exactly what you need to do to understand how black holes and the host galaxies grew up together. There is a way round it however, catch a quasar whose galaxy happens to be bending the light of something further away, and the bending betrays the mass. The catch is that such alignments are vanishingly rare, and the survey that might contain them holds 800,000 quasars. A team at Ohio State set a neural network on the pile and it came back with seven. from Universe Today https://ift.tt/2jGBMxm via IFTTT

The Odds of Finding Water on Mars

Mars has plenty of water, and almost all of it is in the wrong place. The poles are rich in ice, the equator, where you would actually want to land, has none within reach. That leaves the mid-latitudes, and until now the honest answer about what lies beneath them has been a bit of a shrug. Two new studies from the Planetary Science Institute have changed the shape of that answer. Rather than simply asking whether the data are consistent with buried ice, they have started calculating the odds and can now say, of a given patch of Martian ground, that there is a 64 per cent chance of finding ice if you dig there. from Universe Today https://ift.tt/jC6nTxs via IFTTT

The Telescope That Points Itself

Time on a large professional telescope is one of the scarcest resources in science. Astronomers wait months for a few hours, and every one of those hours is a running argument with the weather, the Moon and the atmosphere. Point at the wrong target at the wrong moment and the data comes back soft, washed out, or useless, with the next chance half a year away. A team has now handed that argument to a machine. Their system was trained not on the rules astronomers use but on what astronomers actually did, night after night, for years. from Universe Today https://ift.tt/cPLGude via IFTTT