If dark matter is a particle, it should get inside red giant stars and change the way they behave

This artist’s impression shows the red supergiant star. Using ESO’s Very Large Telescope Interferometer, an international team of astronomers have constructed the most detailed image ever of this, or any star other than the Sun. Credit: ESO/M. Kornmesser

Dark matter makes up the vast majority of matter in the universe, but we can’t see it. At least, not directly. Whatever the dark matter is, it must interact with everything else in the universe through gravity, and astronomers have found that if too much dark matter collects inside of red giant stars, it can potentially cut their lifetimes in half.

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Extreme galaxies depend on extreme conditions for their formation

The spiral pattern shown by the galaxy NGC 2275 in this image from the NASA/ESA Hubble Space Telescope is striking because of its delicate, feathery nature. Credit: ESA/Hubble & NASA, J. Lee and the PHANGS-HST Team; Acknowledgment: Judy Schmidt (Geckzilla)

Some galaxies are too small, and some galaxies are too big, while others are just right. A new survey of the nearby Virgo cluster has potentially revealed why extreme galaxies are the wrong size, and how they might be connected.

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A beautiful picture of Saturn’s heavily-cratered moon Mimas, processed by @kevinmgill

Mimas, as imaged by NASA's Cassini spacecraft and processed by @kevinmgill

The Cassini mission to Saturn took many images of Mimas, one of the smallest moons in the solar system. And now you can view it in all its icy, cratered glory, thanks to the work of Kevin Gill.

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Gravitational waves could show what’s happening inside a star as it’s going supernova

A 2-D snapshot of a pair-instability supernovae as the explosion waves are about to break through the star's surface. The tiny disturbances represent fluid instability - in a region where different elements interact and mix. Image Credit: ASIAA/Ken Chen

It’s kind of hard to see inside a star as it’s blowing up, because of the whole “blowing up” part, but gravitational waves – tiny ripples in the fabric of spacetime itself – may help astronomers unlock how the biggest stars die.

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Quasars can twinkle?

This illustration depicts a gas halo surrounding a quasar in the early Universe. The quasar, in orange, has two powerful jets and a supermassive black hole at its centre, which is surrounded by a dusty disc. The gas halo of glowing hydrogen gas is represented in blue. A team of astronomers surveyed 31 distant quasars, seeing them as they were more than 12.5 billion years ago, at a time when the Universe was still an infant, only about 870 million years old. They found that 12 quasars were surrounded by enormous gas reservoirs: halos of cool, dense hydrogen gas extending 100 000 light years from the central black holes and with billions of times the mass of the Sun. These gas stashes provide the perfect food source to sustain the growth of supermassive black holes in the early Universe.

It turns out you can teach an old dog new tricks. With a recent upgrade to a 50-year-old radio telescope, astronomers have spotted nearly a dozen of a rare class of quasars, ones capable of flickering in less than an hour.

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Europa’s entire icy shell shifted 70-degrees a few million years ago

Images from NASA's Galileo spacecraft show the intricate detail of Europa's icy surface. Image: NASA/JPL-Caltech

The mysterious world Europa, the ice-covered second moon of Jupiter, sports deep scars that cut across its face. An international team of investigators studied high-resolution maps of that surface to reveal a pattern: something shook Europa sometime within the past few million years, causing the entire shell to shift by 70 degrees.

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Astronomers find 100 brown dwarfs in our neighborhood

An artist's conception of a brown dwarf. A new study identifies CK Vulpeculae as the remnant of a collison between a brown dwarf and a white dwarf. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons
An artist's conception of a brown dwarf. Brown dwarfs are more massive than Jupiter but less massive than the smallest main sequence stars. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons

Brown dwarfs are smallish objects sitting somewhere between stars and planets, making them notoriously hard to find. But a recent citizen science project aimed at finding the elusive Planet 9 has instead revealed a treasure trove of these oddities, right next door.

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Seeing baby stars at every stage of their formation

Observations of the Taurus Molecular Cloud obtained by the Herschel Space Observatory. Image credit: ALMA (ESO/NAOJ/NRAO), Tokuda et al., ESA/Herschel

Stars form from the collapse of dense clouds of gas and dust, which makes it very hard for astronomers to watch the process unfold. Recently the ALMA telescope has revealed a treasure trove of embryonic stars in the Taurus Molecular Cloud, illuminating how baby stars are born.

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A magnetar has been discovered throwing off bizarre blasts of radiation. Is this where fast radio bursts come from?

Artist's impression of a magnetar throwing off a seriously impressive blast. Image credit: ESA

Magnetars are the ultimate aggressive star: intense magnetic fields, massive outbursts, the works. We’ve known that magnetars are capable of producing some of the most powerful blasts in the cosmos, but new observations reveal a different kind of radiation: radio waves. This could potentially solve the long-standing puzzle of the origins of the mysterious Fast Radio Bursts.

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