exoplanet Archives

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!

September 27, 2024September 27, 2024 by Mark Thompson

Astronomers Find a Strange Lopsided Planet

Artist's illustration of the exoplanet WASP-107 b based on transit observations from NASA's James Webb Space Telescope as well as other space- and ground-based telescopes, led by Matthew Murphy of the University of Arizona and a team of researchers around the world.

I’ve often stated that planets come in a wide range of sizes but rarely do I find myself stating they come in a wide range of shapes too! The discovery of WASP-107b is a case in point since this planet is the size of Jupiter but only a tenth of its mass. But there’s more… Using the James Webb Space Telescope a team of astronomers have accurately identified that the planet has an east-west asymmetry in its atmosphere, in other words, it’s lopsided. It is tidally locked to the star and on one side, the atmosphere seems to be inflated compared to the other.

September 18, 2024September 18, 2024 by Brian Koberlein

SETI Scientists Scan TRAPPIST-1 for Technosignatures

Three of the TRAPPIST-1 planets – TRAPPIST-1e, f and g – dwell in their star’s so-called “habitable zone. CreditL NASA/JPL

If you are going to look for intelligent life beyond Earth, there are few better candidates than the TRAPPIST-1 star system. It isn’t a perfect choice. Red dwarf stars like TRAPPIST-1 are notorious for emitting flares and hard X-rays in their youth, but the system is just 40 light-years away and has seven Earth-sized worlds. Three of them are in the potentially habitable zone of the star. They are clustered closely enough to experience tidal forces and thus be geologically active. If intelligent life arises easily in the cosmos, then there’s a good chance it exists in the TRAPPIST-1 system.

September 9, 2024September 9, 2024 by Mark Thompson

Iron Winds are Blowing on WASP-76 b

WASP-76 b has been the subject of numerous studies since its discovery in 2013. The temperature there reaches 2,400 degrees Celsius. © Tania Cunha (Planetário do Porto - Centro Ciência Viva/Instituto de Astrofísica e Ciências do Espaço)

Exoplanets have been discovered with a wide range of environmental conditions. WASP-76b is one of the most extreme with a dayside temperature of over 2,000 degrees. A team of researchers have found that it’s even more bizarre than first thought! It’s tidally locked to its host star so intense winds encircle the planet. They contain high quantities of iron atoms that stream from the lower to upper layers around the atmosphere.

August 31, 2024August 31, 2024 by Mark Thompson

By Watching the Sun, Astronomers are Learning More about Exoplanets

Illustration of the Sun seen from Mercury

Watching the Olympics recently and the amazing effort of the hammer throwers was a wonderful demonstration of the radial velocity method that astronomers use to detect exoplanets. As the hammer spins around the athlete, their body and head bobs back and forth as the weight from the hammer tugs upon them. In the same way we can detect the wobble of a star from the gravity of planets in orbit. Local variations in the stars can add noise to the data but a team of researchers have been studying the Sun to help next-generation telescopes detect more Earth-like planets.

August 26, 2024August 26, 2024 by Mark Thompson

X-Ray Telescopes Could Study Exoplanets Too

Exoplanets are often discovered using the transit method (over three quarters of those discovered have been found this way.) The same transit technique can be used to study them, often revealing detail about their atmosphere. The observations are typically made in visible light or infrared but a new paper suggests X-rays may be useful too. Stellar wind interactions with the planet’s atmosphere for example would lead to X-ray emissions revealing information about the atmosphere. As we further our exploration of exoplanets we develop our understanding of our own Solar System and ultimately, the origins of life in the Universe.

August 25, 2024August 25, 2024 by Laurence Tognetti

The Big Fringe Telescope. A 2.2 KILOMETER Telescope on the Cheap. And it Can Make Exoplanet “Movies”.

Can a kilometer-scale telescope help conduct more efficient science, and specifically for the field of optical interferometry? This is what a recently submitted study hopes to address as a pair of researchers propose the Big Fringe Telescope (BFT), which is slated to comprise 16 telescopes 0.5-meter in diameter and will be equivalent to a telescope at 2.2 kilometers in diameter. What makes BFT unique is its potential to create real-time exoplanet “movies” like the movies featuring Venus transiting our Sun, along with significantly reduced construction costs compared to current ground-based optical interferometers.

August 10, 2024August 11, 2024 by Laurence Tognetti

Good Thing We Found this Earth-Sized Planet Now. It’s About to Be Destroyed

Illustration of an Earth-sized world. (Credit: NASA/JPL-Caltech/Robert Hurt)

Astronomers have confirmed the existence of exoplanets with extremely small orbits around their stars. But what about exoplanets that get close enough to be devoured by their star, and what if it’s an Earth-sized exoplanet? This is what a recent study accepted to AAS Journals hopes to address as an international team of more than 50 researchers investigated an Earth-sized exoplanet with an orbital period of only 5.7 hours, known as “ultra-short-period” (USP) exoplanets, that could eventually experience what’s known as tidal disruption, resulting in its devourment by its star. This study holds the potential to help researchers better understand the processes responsible for this, along with continuing to challenge our understanding of exoplanetary architectures, as well.

August 5, 2024August 5, 2024 by Mark Thompson

Astronomers See Planets Forming Around Binary Stars

Artist's illustration of binary star planet formation. Credit: S. Dagnello, NSF/AUI/NRAO

Over 5,000 exoplanets have been discovered around distant star systems. Protoplanetary disks have been discovered too and it’s these, out of which all planetary systems form. Such disks have recently been found in two binary star systems. The stellar components in one have a separation of 14 astronomical units (the average distance between the Earth and Sun is one astronomical unit) and the other system has a separation of 22 astronomical units. Studying systems like these allow us to see how the stars of a binary system interact and how they can distort protoplanetary disks.

July 25, 2024July 25, 2024 by Mark Thompson

Why is JWST Having So Much Trouble with the TRAPPIST-1 System?

A new step-by-step roadmap describes how to improve the efficiency of data gathering with the JWST to benefit the astronomy community at large. “Our hope now is that a large-scale community effort guided by the roadmap can be initiated to yield deliverables at a timely pace,” says MIT Associate Professor Julien de Wit. Credits:Image components courtesy of NASA/JPL-Caltech.

When the James Webb Space Telescope was launched it came with a fanfare expecting amazing things, much like the Hubble Space Telescope. One of JWST’s most anticipated target was TRAPPIST-1. This inconspicuous star is host to seven Earth-sized planets, with at least three in the habitable zone. The two inner planets are airless worlds but so far there has been no word of the third planet, the first in the habitable zone. The question is why and what makes it so tricky to observe?