Supermassive black holes can cloak themselves in a cocoon of dust, making them invisible even when they should be bright quasars

Artist's impression of a shroud of dust cloaking a supermassive black hole, alongside the X-ray view of where black holes should be. Image credit: X-ray: NASA/CXC/Penn State/B.Luo et al; Illustration: NASA/CXC/M. Weiss

Quasars are the most powerful sources of light in the universe, but sometimes they’re hard to find. A team of astronomers used the Chandra X-ray Space Telescope to find some diamonds in the rough.

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There’s a flash of ultraviolet just as a white dwarf is exploding as a supernova

Artist's impression of a supernova. Supernovae bombarded Earth with radiation that has implications for the development of life on Earth. Image Credit: NASA

Astronomers recently spotted a rare type of supernova explosion that was accompanied by a massive flare of ultraviolet radiation. Untangling the mystery of the UV flash could help unravel the mysterious nature of these supernova explosions, and even help us understand the age of the universe.

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A ring of high-energy particles surrounding a black hole suddenly disappeared

If we could see the blazar 3C 354.3 up close it would look something like this. A bright accretion disk surrounds a black hole. Twin jets of radiation beam from the center. Credit: Cosmovision

In March 2018 astronomers watched a massive black hole surge in brightness. Then over the following year, its ring of light dimmed to near-invisibility before regaining its former strength. The potential culprit? The black hole swallowing an entire star.

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A Neptune-class exoplanet has been found with its atmosphere stripped away

Voyager 2 captured this image of Neptune in 1982, when it was over 7 million km (4.4 million miles) away from the planet. The Great Dark Spot in the middle of the image was the first storm ever seen on Neptune. Image: By NASA (JPL image) [Public domain], via Wikimedia Commons

What happens when a giant planet gets stripped of its atmosphere? It leaves behind a giant core, rich in iron and other metals. A team using NASA’s TESS mission recently found such a remnant core, orbiting a star just 730 light-years away.

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Supernovae shockwaves aren’t spherical

Artist’s impression of gamma-ray burst with orbiting binary star. Credit: University of Warwick/Mark Garlick

When stars blow up, they tend to release their energy in a roughly spherical shape. But much after the initial blast, the resulting shock waves can sometimes be elongated in one direction. A team of theorists used laboratory lasers to identify the potential culprit: magnetic fields.

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White dwarfs are a big source of carbon in the Universe

Artist's rendition of a white dwarf from the surface of an orbiting exoplanet. Astronomers have found two giant planet candidates orbiting two white dwarfs. More proof that giant planets can surve their stars' red giant phases. Image Credit: Madden/Cornell University

In their nuclear hearts, stars fuse elements heavier than hydrogen, creating the ingredients necessary to make planets, oceans, and people. Tracing the origins of individual elements in the Milky Way has been a challenge, but a new analysis of white dwarf stars reveals that they may be responsible for one of the most essential elements of all: carbon.

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New Zealand just got its first International Dark Sky Park

A Perseid meteor streaks across the northeastern sky two Augusts ago. This year's shower will peak on the night of August 12-13 with up to 100 meteors per hour visible from a dark sky. Credit: Bob King

As light pollution around the world increases, we are losing our access to the night sky. Thankfully, dark sky preserves and parks do exactly what their names suggest – preserve the night sky as our ancestors knew it. And recently, the Wai-iti Recreational Reserve and Tunnicliff Forest has been accredited, offering stargazers in New Zealand unprecedented views of the heavens above.

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Finally! We’ve got a comet that’s visible to the unaided eye. Comet C/2020 F3 NEOWISE

Comet NEOWISE as seen from the International Space Station in a photograph shared by Russian cosmonaut Ivan Vagner on July 4, 2020. (Image credit: Ivan Vagner/Roscosmos/NASA)

Look up! A rare naked-eye comet, C/2020 F3 (NEOWISE), is now visible to the unaided eye. But act fast – this celestial treat won’t last long.

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It might just be possible to see a light flash too when black holes merge

Artist's concept of a supermassive black hole and its surrounding disk of gas. Embedded within this disk are two smaller black holes orbiting one another.
Artist's concept of a supermassive black hole and its surrounding disk of gas. Embedded within this disk are two smaller black holes orbiting one another. Image credit: Caltech/R. Hurt (IPAC)

Black hole merger events are some of the most energetic, fearsomely energetic events in all the cosmos. When black holes merge, they’re entirely invisible, the only evidence of the cataclysm some faint whisper of gravitational waves. Until now.

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A brand new magnetar found, it’s only 240 years old

A massive flare ejected from a magnetar.

Magnetars are some of the most ridiculous objects in the universe. Composed of the densest material possible spinning faster than your kitchen blender, they generate the absolute most powerful magnetic fields the cosmos has ever seen – and astronomers have recently spotted a newborn.

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