Exoplanet atmospheres Archives

December 31, 2023December 31, 2023 by Laurence Tognetti

TRAPPIST-1c Isn’t the Exo-Venus We Were Hoping For. But Don’t Blame the Star

A recent study accepted to The Astrophysical Journal uses computer models to investigate why the exoplanet, TRAPPIST-1c, could not possess a thick carbon dioxide (CO2) atmosphere despite it receiving the same amount of solar radiation from its parent star as the planet Venus receives from our Sun, with the latter having a very thick carbon dioxide atmosphere. This study comes after a June 2023 study published in Nature used data from NASA’s James Webb Space Telescope (JWST) to ascertain that TRAPPIST-1c does not possess a carbon dioxide atmosphere. Both studies come as the TRAPPIST-1 system, which is located approximately 41 light-years from Earth and orbits its star in just 2.4 days, has received a lot of attention from the scientific community in the last few years due to the number of confirmed exoplanets within the system and their potential for astrobiology purposes.

December 14, 2023December 15, 2023 by Laurence Tognetti

A Tiny Telescope is Revealing “Hot Jupiter” Secrets

CUTE spacecraft and an artist's impression of a hot Jupiter. (Credit: NASA/JPL, University of Colorado)

A recent study presented this week at the 2023 meeting of the American Geophysical Union discusses observations of “hot Jupiters” from the NASA-funded CubeSat mission known as the Colorado Ultraviolet Transit Experiment (CUTE). Unlike most exoplanet-hunting telescopes, whose sizes are comparable to a small school bus, CUTE measures 36 centimeters (14 inches) in length, equivalent to the size of a cereal box. These findings come after members of the team, which consists of undergraduate and graduate students, published an overview paper about CUTE in The Astronomical Journal in January 2023 and results from CUTE observing WASP-189b in The Astrophysical Journal Letters in August 2023.

December 6, 2023December 6, 2023 by Evan Gough

ESA’s Ariel Mission is Approved to Begin Construction

An artist's impression of the ESA's Ariel space telescope. It'll examine 1,000 exoplanet atmospheres. Image Credit: ESA

We’re about to learn a lot more about exoplanets. The ESA has just approved the construction of its Ariel mission, which will give us our first large survey of exoplanet atmospheres. The space telescope will help us answer fundamental questions about how planets form and evolve.

October 27, 2023October 27, 2023 by Evan Gough

JWST Sees Four Exoplanets in a Single System

This artist’s rendering shows the star HR 8799 and one of its four planets, HR 8799c. It illustrates the system at an early stage of evolution. It also shows the star's dusty disk and rocky inner planets. Credit: Dunlap Institute for Astronomy & Astrophysics

When the JWST activated its penetrating infrared eyes in July 2022, it faced a massive wish-list of targets compiled by an eager international astronomy community. Distant, early galaxies, nascent planets forming in dusty disks, and the end of the Universe’s dark ages and its first light were on the list. But exoplanets were also on the list, and there were thousands of them beckoning to be studied.

But one distant solar system stood out: HR 8799, a system about 133 light-years away.

October 18, 2023October 18, 2023 by Laurence Tognetti

An Exoplanet so Hot it has Clouds Made of Quartz

Artist illustration showing what WASP-17 b could look like based on data obtained from a myriad of ground- and space-based telescopes, including NASA’s Hubble, Webb, and the retired Spitzer space telescopes. This most recent study used MIRI (Webb’s Mid-Infrared Instrument) to identify nanocrystals of quartz within the clouds WASP-17 b. (Credit: NASA, ESA, CSA, and R. Crawford (STScI))

A recent study published in The Astrophysical Journal Letters used data obtained by the James Webb Space Telescope’s (JWST) Mid-Infrared Instrument (MIRI) to identify the presence of quartz nanocrystals in the upper atmosphere of WASP-17 b, an exoplanet whose mass and radius are approximately 0.78 and 1.87 that of Jupiter, respectively, and is located approximately 1,324 light-years from Earth. WASP-17 b is classified as a “puffy” hot Jupiter due to its 3.7-day orbital period, meaning the extreme temperatures could cause unique chemical processes to occur within its atmosphere, but the astronomers were still surprised by the findings.

September 14, 2023September 14, 2023 by Laurence Tognetti

Planning is Underway for NASA’s Next Big Flagship Space Telescope

Artist rendition of a starshade being used on a future space telescope. This example shows the proposed Habitable Exoplanet Observatory (HabEx), which the 2020 Astrophysics Decadal Survey decided to combine elements of this with the Large Ultraviolet Optical Infrared Surveyor (LUVOIR) for a new flagship telescope, which is now known as the Habitable Worlds Observatory (HWO). (Credit: NASA)

NASA’s James Webb Space Telescope (JWST) has only been operational for just over a year, but this isn’t stopping the world’s biggest space agency from discussing the next big space telescope that could serve as JWST’s successor sometime in the future. Enter the Habitable Worlds Observatory (HWO), which was first proposed as NASA’s next flagship Astrophysics mission during the National Academy of Sciences’ Decadal Survey on Astronomy and Astrophysics 2020 (Astro2020). While its potential technological capabilities include studying exoplanets, stars, galaxies, and a myriad of other celestial objects for life beyond Earth, there’s a long way to go before HWO will be wowing both scientists and the public with breathtaking images and new datasets.

September 13, 2023September 13, 2023 by Brian Koberlein

Has the First Biosignature Been Found on an Exoplanet?

Artist's impression of Earth in the early Archean with a purplish hydrosphere and coastal regions. Even in this early period, life flourished and was gaining complexity. Credit: Oleg Kuznetsov — Artist's impression of Earth in the early Archean with a purplish hydrosphere and coastal regions. Even in this early period, life flourished and was gaining complexity, and distant exoplanets might begin similarly. Credit: Oleg Kuznetsov

Recently I wrote about the discovery of a hycean world. A potentially habitable exoplanet with a deep warm ocean and thick, hydrogen-rich atmosphere. Such planets are thought to be somewhat common orbiting red dwarf stars, and they are an excellent candidate for life. While it’s an exciting discovery, buried in the research article was something even more exciting. Tentative evidence of a biosignature, hinting at the presence of life. You can guess which discovery started making headlines. But have astronomers really found life on another planet?

September 1, 2023September 1, 2023 by Brian Koberlein

If Earth Was an Exoplanet, JWST Would Know There's an Intelligent Civilization Here

Sunrise over the Gulf of Saint Lawrence. Credit: NASA's Earth Observatory

Yesterday I presented a rather pessimistic view about our chances of finding evidence of alien civilizations. That work focused on detecting physical structures on an alien planet, which would take an optical telescope array the size of Saturn’s orbit. Today I’ll talk about a more optimistic view, one which focuses not on physical structures, but the fingerprint of molecules in an alien atmosphere. It’s a task that is not only much easier, it’s something we could do now using the James Webb Space Telescope (JWST).

August 31, 2023September 1, 2023 by Laurence Tognetti

Astronomers Confirm First Exoplanet “Thermometer Molecule” that is Typically Used to Study Brown Dwarfs

Artist impression of "hot Jupiter" exoplanet, WASP-31 b. (Credit: ESA/Hubble & NASA)

A recent study published in The Astrophysical Journal Letters examines a rare alloy molecule known as chromium hydride (CrH) and its first-time confirmation on an exoplanet, in this case, WASP-31 b. Traditionally, CrH is only found in large quantities between 1,200 to 2,000 degrees Kelvin (926.85 to 1,726.85 degrees Celsius/1700 to 3,140 degrees Fahrenheit) and used to ascertain the temperature of cool stars and brown dwarfs. Therefore, astronomers like Dr. Laura Flagg in the Department of Astronomy and Carl Sagan Institute at Cornell University refer to CrH as a “thermometer for stars”.

July 28, 2023July 28, 2023 by Alan Boyle

How Will We the Find First Signs of Alien Life — and When?

Illustration: Assortment of exoplanets — Astronomers have detected thousands of planets, including dozens that are potentially habitable. (NASA Illustration)

When will we find evidence for life beyond Earth? And where will that evidence be found? University of Arizona astronomer Chris Impey, the author of a book called “Worlds Without End,” is betting that the first evidence will come to light within the next decade or so.

But don’t expect to see little green men or pointy-eared Vulcans. And don’t expect to get radio signals from a far-off planetary system, as depicted in the 1992 movie “Contact.”

Instead, Impey expects that NASA’s James Webb Space Telescope — or one of the giant Earth-based telescopes that’s gearing up for observations — will detect the spectroscopic signature of biological activity in the atmosphere of a planet that’s light-years away from us.

“Spectroscopic data is not as appealing to the general public,” Impey admits in the latest episode of the Fiction Science podcast. “People like pictures, and so spectroscopy never gets its fair due in the general talk about astronomy or science, because it’s slightly more esoteric. But it is the tool of choice here.”