What Would Happen to Earth if a Rogue Star Came Too Close?

The speeding rogue star Kappa Cassiopeiae sets up a glowing bow shock in this Spitzer image (NASA/JPL-Caltech)

Stars are gravitationally fastened to their galaxies and move in concert with their surroundings. But sometimes, something breaks the bond. If a star gets too close to a supermassive black hole, for example, the black hole can expel it out into space as a rogue star.

What would happen to Earth if one of these stellar interlopers got too close?

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JWST Detects Carbon Dioxide in a Centaur for the First Time

Centaurs are small planetary bodies that orbit between Jupiter and Neptune and have baffled astronomers for sharing characteristics with both asteroids and comets. Centaurs got their name after the mythical half-horse, half-human creatures called centaurs due to their dual characteristics. Above is an artist's illustration displaying a centaur creature among asteroids (left) and comets (right). (Credit: NASA/JPL-Caltech)

A study published today in The Planetary Science Journal examines how NASA’s James Webb Space Telescope (JWST) has conducted a first-time detection of carbon dioxide in a Centaur, this one designated 39P/Oterma. A Centaur is a small planetary body that orbits between Jupiter and Neptune and frequently crosses the orbits of one or more of the gas giant planets within our solar system. While no Centaur has been imaged up-close, they typically exhibit a combination of attributes between comets and asteroids. While carbon monoxide has been detected in two known centaurs, this recent discovery could mark a turning point in how scientists understand the formation, evolution, and composition of not only Centaurs, but of the early solar system, as well.

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Io has 266 Active Volcanic Hotspots Linked by a Global Magma Ocean

NASA’s Galileo spacecraft captured this image of a volcanic eruption on Io in 1997. Image Credit:NASA, NASA-JPL, DLR

Jupiter’s Io stands apart from the Solar System’s other moons, with its numerous volcanoes and its surface dominated by lava flows. Io’s surface volcanism was confirmed in 1979 when the Voyager spacecraft imaged it, but its volcanic nature isn’t duplicated anywhere else in our system. Tidal heating is behind the moon’s eruptive nature, driven by Jupiter’s powerful gravity, and by resonance with other moons. But is there a magma ocean inside Io?

A final answer to that question has been elusive, but new research supports the idea of a magma ocean.

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Europa and Enceladus are the Perfect Targets for a Lightsail Mission

Saturn's moon Enceladus isn't just bright and beautiful. It has an ocean under all that ice that has chemicals necessary for life. Image Credit: NASA, ESA, JPL, SSI, Cassini Imaging Team

There’s always a need for new technologies or for novel uses of existing technologies to lower the cost of space exploration and extend our reach. Lightsails are a novel type of spacecraft that could eventually be our first visitors to nearby stars like the Alpha Centauri system. But they could be put to productive use right here in our Solar System.

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Colliding Moons Might Have Created Saturn’s Rings

Saturn's rings are arguably the most recognizable feature in our Solar System and are made mostly of ice particles. New research says a collision between icy moons may have created them in the recent past. Image Credit: NASA/JPL/Space Science Institute

If we could wind the clock back billions of years, we’d see our Solar System the way it used to be. Planetesimals and other rocky bodies were constantly colliding with each other, and new objects would coalesce out of the debris. Asteroids rained down on the planets and their moons. The gas giants were migrating and contributing to the chaos by destroying gravitational relationships and creating new ones. Even moons and moonlets would’ve been part of the cascade of collisions and impacts.

When nature crams enough objects into a small enough space, it breeds collisions. A new study says that’s what happened at Saturn and created the planet’s dramatic rings.

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A Nearby Supernova Almost Destroyed the Solar System Before it Could Form

Artist’s impression of the blast wave from a supernova colliding with the molecular cloud filament where the infant Solar System was forming. Credit: NAOJ
Artist’s impression of the blast wave from a supernova colliding with the molecular cloud filament where the infant Solar System was forming. Credit: NAOJ

Way back in time, about 4.6 billion years ago, our Sun and planets were busily forming nestled inside a cloud of gas and dust. Not far away, a supernova exploded, threatening to tear everything apart. Luckily, a filament of molecular gas protected the infant Solar System from imminent destruction.

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There Could Be Captured Planets in the Oort Cloud

An icy planet distantly orbiting its star. Credit: NASA/JPL-Caltech

Our solar system has had a chaotic past. Earth and the other planets are now in stable orbits, but while they were forming they experienced drastic location shifts. Jupiter was likely much closer to the Sun than it is now, and its shift not only shifted other planets but also cleared the solar system of debris, tossing much of it to the Oort Cloud.

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A Few Interstellar Objects Have Probably Been Captured

Artist’s impression of the first interstellar asteroid/comet, "Oumuamua". This unique object was discovered on 19 October 2017 by the Pan-STARRS 1 telescope in Hawaii. Credit: ESO/M. Kornmesser

When Oumuamua travelled through our Solar System back in 2017, people around the world paid attention. It was the first Interstellar Object (ISO) astronomers had ever identified. Then in August 2019, Comet 2I Borisov travelled through our Solar System, becoming the second ISO to cruise through for a visit. Together, the visiting ISOs generated a wave of inquiry and speculation.

There’s bound to be more ISOs than just those two, and a new study says our Solar System has probably captured some of these interstellar visitors, though they don’t stay for long.

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Webb Examined an Asteroid Belt and Found More Than it Bargained For

This image of the dusty debris disc surrounding the young star Fomalhaut is from Webb’s Mid-Infrared Instrument (MIRI). It reveals three nested belts extending out to 23 billion kilometres from the star. Image Credit: NASA, ESA, CSA, A. Pagan (STScI), A. Gáspár (University of Arizona)

One of the things astronomers would love to see is planets forming around other stars. That would help us understand our own Solar System better. But it all happens behind a veil of obscuring dust. The James Webb Space Telescope has the power to see through the veil.

A team of astronomers pointed the JWST at the well-known star Fomalhaut and its dusty debris disk. They found more complexity than they imagined, including hints of planets forming among all that dust and debris.

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What Would Happen if the Solar System Gained a Super-Earth?

This illustration shows the super-Earth exoplanet 55 Cancri e with its star. What would our Solar System be like if it was home to a super-Earth like this one? Credit: NASA/JPL

In this era of exoplanet discovery, astronomers have found over 5,000 confirmed exoplanets, with thousands more awaiting confirmation and many billions more waiting to be discovered. These exoplanets exist in a bewildering spectrum of sizes, compositions, orbital periods, and just about every other characteristic that can be measured.

Learning about them has also shed light on our Solar System. We used to think of it as an archetypal arrangement of planets since it’s all we had to go on. But now we know we might be the outlier because we have no Super-Earth.

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