How Growing Giant Planets Fight for Food

Artistic rendition of a protoplanet forming within the accretion disk of a protostar. Outbursts from newborn and adolescent stars might drive planetary water beneath the surface of rocky worlds. Credit: ESO/L. Calçada http://www.eso.org/public/images/eso1310a/

A new study has shown that in order to grow more than one giant planet in the same solar system, the planets must go through a complicated and intricate dance to prevent one from destroying the other.

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The Voids Closest to Us May Not be Entirely Empty

Map of the nearest voids to the Milky Way galaxy (image credit: Courtois et al.)

The large scale structure of the universe is dominated by vast empty regions known as cosmic voids. These voids appear as holes hundreds of millions of light years across in the distribution of galaxies. However, new research shows that many of them may surprisingly still be filled with dark matter.

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We Have Ignition! Fusion Breakthrough Raises Hopes — and Questions

A color-enhanced image shows the inside of a preamplifier support structure at the National Ignition Facility. (LLNL Photo / Damien Jemison)

For the first time ever, physicists have set off a controlled nuclear fusion reaction that released more energy than what was put into the experiment.

The milestone laser shot took place on Dec. 5 at the U.S. Department of Energy’s National Ignition Facility at Lawrence Livermore National Laboratory in California. The fact that there was a net energy gain qualified the shot, in technical terms, as ignition. “Reaching ignition in a controlled fusion experiment is an achievement that has come after more than 60 years of global research, development, engineering and experimentation,” said Jill Hruby, under secretary of energy for nuclear security and the administrator of the National Nuclear Security Administration.

However, officials acknowledged that it’s still likely to be decades before commercial fusion power becomes a reality. They said the most immediate impact of the breakthrough will be felt in the field of national security and the stewardship of America’s nuclear weapons stockpile.

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Asteroids Didn’t Create the Moon’s Largest Craters. Left-Over Planetesimals Did

The largest impact basin on the Moon is the South-Pole Aitken basin. It, and other impact basins, were created by planetesimals according to a new study. Image Credit: Moriarty et al., 2021.

The Moon’s pock-marked surface tells the story of its history. It’s marked by over 9,000 impact craters, according to the International Astronomical Union (IAU.) The largest ones are called impact basins, not craters. According to a new study, asteroids didn’t create the basins; leftover planetesimals did.

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Orion Splashes Down in the Pacific Ocean, Completing the Artemis I Mission

NASA’s Orion spacecraft for the Artemis I mission splashed down in the Pacific Ocean at 9:40 a.m. PST on Sunday, Dec. 11, after a 25.5 day mission to the Moon. Credit: NASA

On December 11th, at 09:40 a.m. PST (12:40 p.m. EST), NASA’s Artemis I mission splashed down in the Pacific Ocean off the coast of Baja California. The return of the uncrewed Orion spacecraft marks the end of the Artemis Program’s inaugural mission, which launched on November 16th and validated the spacecraft and its heavy launch vehicle – the Space Launch System (SLS). During its 25.5-day circumlunar flight, the Orion spacecraft traveled more than 2.25 million km (1.4 million mi) and flew beyond the Moon’s orbit, establishing a new distance record.

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Webb Completes its First “Deep Field” With Nine Days of Observing Time. What did it Find?

This image taken by the James Webb Space Telescope highlights the region of study by the JWST Advanced Deep Extragalactic Survey (JADES). This area is in and around the Hubble Space Telescope’s Ultra Deep Field. Image Credit: NASA, ESA, CSA, and M. Zamani (ESA/Webb).

About 13 billion years ago, the stars in the Universe’s earliest galaxies sent photons out into space. Some of those photons ended their epic journey on the James Webb Space Telescope’s gold-plated, beryllium mirrors in the last few months. The JWST gathered these primordial photons over several days to create its first “Deep Field” image.

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Black Holes Shouldn’t be Able to Merge, but Dozens of Mergers Have Been Detected. How Do They Do It?

black holes in a globular cluster
This is an artist’s impression created to visualize the concentration of black holes at the center of globular cluster NGC 6397. Credit: ESA/Hubble, N. Bartmann

Who knows what lurks in the hearts of some globular clusters? Astronomers using a collection of gravitational wave observatories found evidence of collections of smaller black holes dancing together as binaries in the hearts of globulars. What’s more, they’ve detected an increased number of gravitational wave events when some of these stellar-mass black holes crashed together.

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Perhaps a Supervoid Doesn’t Explain the Mysterious CMB Cold Spot

The Cosmic Microwave Background's (CMB) "Cold Spot" - a section that is colder than its surroundings. Credit: WMAP Science Team, NASA

For years cosmologists had thought that a strange feature appearing in the microwave sky, known as the CMB cold spot, was due to the light passing through a giant supervoid. But new research casts that conclusion into doubt.

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A Black Hole has been Burping for 100 Million Years

Artist view of an active supermassive black hole. Credit: ESO/L. Calçada

Black holes are gluttonous behemoths that lurk in the center of galaxies. Almost everybody knows that nothing can escape them, not even light. So when anything made of simple matter gets too close, whether a planet, a star or a gas cloud, it’s doomed.

But the black hole doesn’t eat it at once. It plays with its food like a fussy kid. Sometimes, it spews out light.

When the black hole is not only at the center of a galaxy but the center of a cluster of galaxies, these burps and jets carve massive cavities out of the hot gas at the center of the cluster called radio bubbles.

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Life on Proxima b Is Not Having a Good Time

An artist's conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.
An artist's conception of a violent flare erupting from the red dwarf star Proxima Centauri. Such flares can obliterate atmospheres of nearby planets. Credit: NRAO/S. Dagnello.

The nearest known exoplanet to Earth, the planet orbiting Proxima Centauri, experiences some pretty nasty space weather from its parent star. But previous work on the space weather of Proxima relied on a lot of assumptions. The bad news is that new research has confirmed the grim picture.

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