exoplanet Archives

December 12, 2024December 12, 2024 by Brian Koberlein

Early Earth's Oceans of Magma Accelerated the Moon's Departure

Illustration of the exoplanet Corot-7b, which may have lava oceans. Credit: ESO/L. Calçada

The Earth and Moon have been locked in a gravitational dance for billions of years. Each day, as the Earth turns, the Moon tugs upon the oceans of the world, causing the rise and fall of tides. As a result, the Earth’s day gets a little bit longer, and the Moon gets a little more distant. The effect is small, but over geologic time it adds up. About 620 million years ago, a day on Earth was only 22 hours long, and the Moon was at least 10,000 km closer than it is now.

December 3, 2024December 3, 2024 by Brian Koberlein

White Dwarfs Could Have Habitable Planets, Detectable by JWST

An Earth-sized remnant of a Sun-like star is ringed by dust and debris. Credit: NASA’s Goddard Space Flight Center/Scott Wiessinger

In a few billion years, our Sun will die. It will first enter a red giant stage, swelling in size to perhaps the orbit of Earth. Its outer layers will be cast off into space, while its core settles to become a white dwarf. Life on Earth will boil away, and our planet itself might be consumed by the Sun. White dwarfs are the fate of all midsize stars, and given the path of their demise, it seems reasonable to assume that any planets die with their sun. But the fate of white dwarf planets may not be lifeless after all.

December 1, 2024December 1, 2024 by Mark Thompson

Just Built a Giant, Next Generation Planet Hunting Space Telescope? Here’s Where to Point It

LIFE will have five separate space telescopes that fly in formation and work together to detect biosignatures in exoplanet atmospheres. Image Credit: LIFE, ETH Zurich

You know what it’s like. You get a new telescope and need to know where to point it! The bigger the telescope, the more potential targets and the harder the decision! To date, we have found over 5,000 confirmed exoplanets (5,288 to be exact) with thousands more candidates. With missions like Gaia identifying thousands of nearby stars like our Sun where Earth-like planets could be lurking, its time to hunt them down. A new paper takes on the goiath task of trying to filter down all the millions of candidates into about 1,000 main sequence stars or binaries worth exploring. From these, they have identified 100 most promising targets and from them, the 10 best planetary systems.

November 23, 2024November 23, 2024 by Scott Alan Johnston

Astronomers Find a 3 Million Year Old Planet

An artistic interpretation of the IRAS 04125+2902 (TIDYE-1) system. Young stars like this are covered in starspots—regions cooler than the surrounding stellar surface. The inner disk is depleted, leaving an intact outer disk that forms a donut-like structure around the host star. The outer disk is nearly face-on, in contrast to the edge-on planet orbit around the host star. This allows for an unobstructed view of the system. If the disk were also edge-on, it would block the planet and host star, preventing the discovery. Credit: NASA/JPL-Caltech/R. Hurt, K. Miller (Caltech/IPAC)

Astronomers have just found one of the youngest planets ever. At only 3 million years old, planet TIDYE-1b (also known as IRAS 04125+2902 b) is practically in its infancy. By comparison, Earth is 4.5 billion years old: that’s 1500 times older. The discovery of a planet this young can teach scientists a lot about the early stages of planet formation, and the peculiarities of this particular one have scientists re-evaluating their models of planetary birth.

November 14, 2024November 14, 2024 by Mark Thompson

Interferometry Will Be the Key to Resolving Exoplanets

The setting Sun dips below the horizon of the Pacific Ocean, bathing the Paranal platform in light in this amazing aerial image from the Atacama Desert in northern Chile. The Cerro Paranal mountain top is home to the world’s most advanced ground-based facility for astronomy, hosting the four 8.2-metre Unit Telescopes of the Very Large Telescope, four 1.8-metre Auxiliary Telescopes and the VLT Survey Telescope (VST) — all of which are visible in this image. The 4.1-metre Visible and Infrared Survey Telescope for Astronomy (VISTA), also housed at Cerro Paranal, is hidden out of frame.

When it comes to telescopes, bigger really is better. A larger telescope brings with it the ability to see fainter objects and also to be able to see more detail. Typically we have relied upon larger and larger single aperture telescopes in our attempts to distinguish exoplanets around other stars. Space telescopes have also been employed but all that may be about to change. A new paper suggests that multiple telescopes working together as interferometers are what’s needed.

October 26, 2024October 26, 2024 by Mark Thompson

Webb Scans Vega for Planets

To northern sky watchers, Vega is a familiar sight in the summer sky. It’s one of the brightest stars in the sky and in 2013, astronomers detected a large ring of rocky debris surrounding the planet. The prospect of planets suddenly became a real possibility so astronomers turned the James Webb Space Telescope (JWST) on the star. The hunt achieved 10 times the sensitivity of previous ground based searches but alas no planets were discovered.

October 26, 2024October 26, 2024 by Mark Thompson

Red Dwarf Stars Might Be Able to Hold Onto Their Atmospheres After All

This 2018 artist’s concept shows what the TRAPPIST-1 planetary system may look like, based on available data about the planets’ diameters, masses and distances from the host star (far left). New research shows that while TRAPPIST-1b, second from the left, has no atmosphere, TRAPPIST-1e, third from the right, could have a long-term stable atmosphere.NASA/JPL-Caltech

Exoplanets are a fascinating aspect of the study of the Universe. TRAPPIST-1 is perhaps one of the most intriguing exoplanet systems discovered to date with no less than 7 Earth-sized worlds. They orbit a red dwarf star which can unfortunately be a little feisty, hurling catastrophic flares out into space. These flares could easily strip atmospheres away from the alien worlds rendering them uninhabitable. A new piece of research suggests this may not be true and that the rocky planets may be able to maintain a stable atmosphere after all.

October 15, 2024October 15, 2024 by Mark Thompson

Hubble and New Horizons Look at Uranus at the Same Time

Ever since the advent of space exploration we have seen some amazing images of the planets. New technology often brings with it a new perspective and we have been reminded of this again just recently with images from the Hubble Space Telescope (HST) and New Horizons spacecraft. The two objects simultaneously imaged Uranus from different perspectives in an attempt to predict what astronomers would see when they look at exoplanets orbiting other stars.

October 10, 2024October 10, 2024 by Mark Thompson

A New Way to Detect Rocky Exoplanet Atmospheres

University of Chicago astronomers have tested a simpler, and more accurate way to determine whether or not exoplanets have atmospheres, a leap in learning more about the potential habitability of far-away planets. Above, an artist’s rendering of what terrestrial exoplanet GJ 1132 b may look like.

The total number of exoplanets discovered to date totals 5,288. Among them are a host of rocky, Earth-like exoplanets but none of them seem to have atmospheres. It’s a fairly challenging observation to make but a team of researchers think they’ve come up with a new, simpler technique. It involves measuring the combined temperature of a star and the exoplanet just before the planet passes behind. If it’s lower than expected, the planet is likely to have an atmosphere regulating its temperature!

October 8, 2024October 8, 2024 by Mark Thompson

TESS Finds a Triple Star System that Could Fit within Mercury’s Orbit

This artist’s concept illustrates how tightly the three stars in the system called TIC 290061484 orbit each other. If they were placed at the center of our solar system, all the stars’ orbits would be contained a space smaller than Mercury’s orbit around the Sun. The sizes of the triplet stars and the Sun are also to scale. NASA’s Goddard Space Flight Center

TESS, the Transiting Exoplanet Survey Satellite has been on the lookout for alien worlds since 2018. It has just hit the news again having identified an extreme triple star system where two stars orbit each other every 1.8 days. The third component circles them both in 25 days – this puts the entire system within the orbit of Mercury with a little wriggle room to spare! To visual observers, it looks like a single star but the power of TESS revealed a flicker as the stars line up and pass one another along our line of sight. Eventually, the two inner stars will merge, triggering a supernova event!