One in Ten Stars Ate a Jupiter (Or Bigger)

This illustration shows a Jupiter-mass exoplanet getting perilously close to its star. Eventually, the star will engulf the planet, something that happens in many stars' lives as they leave the main sequence. Image Credit: C. Carreau / ESA.

In space, cataclysmic events happen to stars all the time. Some explode as supernovae, some get torn apart by black holes, and some suffer other fates. But when it comes to planets, stars turn the tables. Then it’s the stars who get to inflict destruction.

Expanding red giant stars consume and destroy planets that get too close, and a new study takes a deeper look at the process of stellar engulfment.

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Building Planetary Systems That Could Last Forever

A vision of parallel Earths. Credit: Lee Davy, via flickr, CC BY 2.0

Vacations can be quite enjoyable. Visiting historic cities, lounging in the Sun on a tropical beach, or snuggling up at a cozy mountain resort. But while the destinations are great, traveling itself can be a chore. Crowds, cramped flights, delays. It would be great if there were some short cut to our destination. Now imagine the vacationers of a galactic empire. It’s great to visit the diamond shores of Exoticon 5, but nobody enjoys all that mucking about in hyperspace. So why not bring these worlds closer to home? That’s the idea behind a study recently published in MNRAS. It basically looks at how a super-advanced civilization might pack a bunch of planets into the habitable zone of a single star.

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NASA Uses Powerful Transmitters to Talk to Deep Space Spacecraft. Will Other Civilizations Receive Those Signals?

Artist rendition of Voyager 1 entering interstellar space. (Credit: NASA/JPL-Caltech)

In a recent study submitted to the Publications of the Astronomical Society of the Pacific, a pair of researchers from the University of California, Los Angeles (UCLA) and the University of California, Berkeley (UC Berkeley) examine the likelihood of extraterrestrial intelligent civilizations intercepting outward transmissions from NASA’s Deep Space Network (DSN) that are aimed at five deep space spacecraft: Voyager 1, Voyager 2, Pioneer 10, Pioneer 11, and New Horizons. Members of the public are free to track such transmissions at DSN Now, which displays real-time data of outgoing and incoming transmissions to all spacecraft at various times.

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Chasing SpaceX: The Commercial Space Race Gets a Reality Check

Astra, Firefly Aerospace and Rocket Lab build rockets, while Planet Labs builds satellites. (Credits: Astra / Firefly / Rocket Lab / NASA)

Can anyone keep up with SpaceX in the commercial space race?

It might be one of the four companies profiled in “When the Heavens Went on Sale” — a new book written by Ashlee Vance, the tech journalist who chronicled SpaceX founder Elon Musk’s feats and foibles eight years ago. Or it might be one of the dozens of other space ventures that have risen up to seek their fortune on the final frontier. Or maybe no one.

The space race’s ultimate prizes may still be up for grabs, but in Vance’s view, one thing is clear: There wouldn’t be a race if it weren’t for Musk and SpaceX.

“Elon sort of set this whole thing in motion,” Vance says in the latest episode of the Fiction Science podcast. “My book is more or less a story of people who want to be the next Elon Musk.”

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We Can Only Bring 30 Samples of Mars Back to Earth. How Do We Decide?

NASA’s Perseverance rover puts its robotic arm to work around a rocky outcrop called “Skinner Ridge” in Mars’ Jezero Crater. Perseverance gathered an important sample of sedimentary rock here. Credit: NASA/JPL-Caltech/ASU/MSSS

The Mars Sample Return Mission is one of the most ambitious missions ever conceived. Though the samples won’t be returned to Earth until 2033 at the earliest, the Perseverance Rover is busy collecting them right now. Ideally, Perseverance could gather as many samples as we like and ship them all back to Earth. But of course, that’s not possible.

There are limitations, and this means that choosing which samples to return to Earth is an extremely critical task.

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What Does the Milky Way Look Like?

Artist's impression of the Milky Way Galaxy. Credit: ESO

Beginning in 1610, when famed Renaissance polymath Galileo Galilei observed the night sky using a telescope of his own manufacture, astronomers gradually realized that our Solar System is part of a vast collection of stars known today as the Milky Way Galaxy. By the 20th century, astronomers had a good idea of its size and structure, which consisted of a central “bulge” surrounded by an extended disk with spiral arms. Despite all we’ve learned, determining the true morphology of the Milky Way has remained a challenge for astronomers.

Since we, the observers, are embedded in the Milky Way’s disk, we cannot see through the center and observe what’s on the other side. Using various methods, though, astronomers are getting closer to recreating what a “birds-eye” view of the galaxy would look like. For instance, a team of researchers from the Chinese Academy of Sciences (CAS) used the precise locations of very young objects in our galaxy (for the first time) to measure the morphology of the Milky Way. This revealed a multiple-arm morphology consisting of two symmetrical arms in the inner region and many irregular ones in the outer region.

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JWST Fails to Disprove the Big Bang

A portion of the Renaissance Simulation centered on a cluster of young galaxies. Credit: Advanced Visualization Lab, National Center for Supercomputing Applications

The James Webb Space Telescope (JWST) is revolutionizing our understanding of the early universe. With a mirror larger than Hubble and the ability to observe deep into the infrared, JWST is giving us a detailed view of that period of the universe when galaxies were just starting to form. The results have been surprising, leading some to argue that they disprove the big bang. But the big bang is still intact, as a recent study shows.

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LISA Will Be a Remarkable Gravitational-Wave Observatory. But There’s a Way to Make it 100 Times More Powerful

Artist's impression of the Laser Interferometer Space Antenna (LISA). Credit: ESA

The first-time detection of Gravitational Waves (GW) by researchers at the Laser Interferometer Gravitational-wave Observatory (LIGO) in 2015 triggered a revolution in astronomy. This phenomenon consists of ripples in spacetime caused by the merger of massive objects and was predicted a century prior by Einstein’s Theory of General Relativity. In the coming years, this burgeoning field will advance considerably thanks to the introduction of next-generation observatories, like the Laser Interferometer Space Antenna (LISA).

With greater sensitivity, astronomers will be able to trace GW events back to their source and use them to probe the interiors of exotic objects and the laws of physics. As part of their Voyage 2050 planning cycle, the European Space Agency (ESA) is considering mission themes that could be ready by 2050 – including GW astronomy. In a recent paper, researchers from the ESA’s Mission Analysis Section and the University of Glasgow presented a new concept that would build on LISA – known as LISAmax. As they report, this observatory could potentially improve GW sensitivity by two orders of magnitude.

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Astronomers Watch a Star Gulp Down One of its Planets

A distant Sun-like star will leave the main sequence behind, ending its life of fusion. Then it'll expand into a red giant, totally destroying its four planets. Image Credit: fsgregs Creative Commons Attribution-Share Alike 3.0 Unported

A star like our Sun only shines the way it does because of its intrinsic balance. Stars are massive, and the inward gravitational pressure from all that mass acts to contain the outward thermal pressure from all the fusion inside the star. They are in equilibrium, or on the main sequence if you like, and the result is a spherical mass of plasma that holds its shape and emits radiation with relative stability for billions of years. Like our Sun.

But eventually, stars teeter over the edge and lose their balance. Stars like our Sun will expand, take on a malevolent red hue, and begin to destroy anything that comes within their grasp.

Like a planet.

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