1 in 10 Red Giants are Covered in Spots, and They Rotate Surprisingly Quickly

Artist's impression of a red giant star. If the star is in a binary pair, what happens to its sibling? Credit:NASA/ Walt Feimer

Sunspots are common on our Sun. These darker patches are cooler than their surroundings, and they’re caused by spikes in magnetic flux that inhibit convection. Without convection, those areas cool and darken.

Lots of other stars have sunspots, too. But Red Giants (RGs) don’t. Or so astronomers thought.

A new study shows that some RGs do have spots, and that they rotate faster than thought.

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Stars Like Our Sun Become Lithium Factories as They Die

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

In the beginning, the big bang created three elements: hydrogen, helium, and lithium. But it only produced a trace of lithium. For every lithium atom created, the big bang produced about 10 billion hydrogen atoms, and 3 billion helium atoms. The ratio of primordial elements is one of the triumphs of the big bang model. It predicts the ratio of hydrogen (H) and helium (4He) perfectly, and even works for the ratios of other isotopes, such as deuterium (2H) and helium-3 (3He). But it doesn’t work for lithium, and we aren’t sure why.

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This is a Binary Star in the Process of Formation

Zoom into the Ophiuchus molecular cloud, highlighting the star forming system IRAS 16293-2422 with the proto-star B in the upper right corner and the now clearly identified binary proto-stars A1 and A2 on the bottom left. The binary system is shown also in a further zoom-in panel. Image: © MPE; background: ESO/Digitized Sky Survey 2; Davide De Martin)

About 460 light years away lies the Rho Ophiuchi cloud complex. It’s a molecular cloud—an active star-forming region—and it’s one of the closest ones. R. Ophiuchi is a dark nebula, a region so thick with dust that the visible light from stars is almost completely obscured.

But scientists working with ALMA have pin-pointed a pair of young proto-stars inside all that dust, doing the busy work of becoming active stars.

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Much of the Lithium Here on Earth Came from Exploding White Dwarf Stars

A classical novae contains a white dwarf, and a larger companion star in orbit around it. The white dwarf attracts gas from its companion, leading to a massive explosion. Illustration Credit: David Hardy

The Big Bang produced the Universe’s hydrogen, helium, and a little lithium. Since then, it’s been up to stars (for the most part) to forge the rest of the elements, including the matter that you and I are made of. Stars are the nuclear forges responsible for creating most of the elements. But when it comes to lithium, there’s some uncertainty.

A new study shows where much of the lithium in our Solar System and our galaxy comes from: a type of stellar explosion called classical novae.

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Was Betelgeuse Formed by Merging Stars?

Betelgeuse was the first star directly imaged -- besides our own Sun, of course. Image obtained by the Hubble Space Telescope. Credit: Andrea Dupree (Harvard-Smithsonian CfA), Ronald Gilliland (STScI), NASA and ESA

Modern humans—or Homo Sapiens—have only been around for about 250,000 years. That’s only the blink of an eye in cosmological terms. As it turns out, the star Betelgeuse may only be about the same age.

A new study explores the idea that Betelgeuse formed from a merger of two stars only a few hundred thousand years ago.

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Super-Supernova Released Ten Times More Energy than a Regular Supernova

Artist's conception of SN2016aps, a candidate pulsational pair instability supernova. The explosion energy of SN2016aps, fueled by the shedding of a massive shell of gas, was ten times that of a normal-sized supernova, making SN2016aps the most massive supernova ever identified. Credit: M. Weiss

It’s easy to run out of superlatives and adjectives when your puny human language is trying to describe humongously-energetic events in the Universe. So now it’s down to this: a really powerful supernova is a “super-supernova.”

But whatever name we give it, it’s a monster. A monsternova.

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Astronomers Watch a Nova Go From Start to Finish for the First Time

Artistic representation of a nova eruption: During a nova eruption a white dwarf sucks matter from its companion star and stores this mass on its surface until the gas pressure becomes extremely high. CREDIT © Nova_by K. Ulaczyk, Warschau Universität Observatorium

A nova is a dramatic episode in the life of a binary pair of stars. It’s an explosion of bright light that can last weeks or even months. And though they’re not exactly rare—there are about 10 each year in the Milky Way—astronomers have never watched one from start to finish.

Until now.

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Two White Dwarfs Merged Together Into a Single “Ultramassive” White Dwarf

An artist’s impression of two white dwarfs in the process of merging. Depending on the combined mass, the system may explode in a thermonuclear supernova, or coalesce into a single heavy white dwarf, as with WDJ0551+4135. This image is free for use if used in direct connection with this story but image copyright and credit must be University of Warwick/Mark Garlick

Astronomers have found a white dwarf that was once two white dwarfs. The pair of stars merged into one about 1.3 billion years ago. The resulting star, named WDJ0551+4135, is about 150 light years away.

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Here’s a New Planetary Nebula for Your Collection: CVMP 1

The international Gemini Observatory composite color image of the planetary nebula CVMP 1 imaged by the Gemini Multi-Object Spectrograph on the Gemini South telescope on Cerro Pachón in Chile. Credit: The international Gemini Observatory/NSF’s National Optical-Infrared Astronomy Research Laboratory/AURA

Some stars die a beautiful death, ejecting their outer layers of gas into space, then lighting it all up with their waning energy. When that happens, we get a nebula. Astronomers working with the Gemini Observatory just shared a new image of one of these spectacular objects.

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Bizarre Star Could be the Result of Two White Dwarfs Merging Together

Three images of the infrared nebula J005311. Image Credit: Vasilii Gvaramadse/Moscow University

Stars live and die on epic time scales. Tens of millions of years, hundreds of millions of years, even billions of years or longer. Maybe the only thing that surpasses that epicness is when two dead stars join together and come back to life.

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