Methane Archives

November 13, 2024November 13, 2024 by Evan Gough

Lessons From Ancient Earth’s Atmosphere: From Hostile to Hospitable

Earth's ancient atmosphere was much different than now. How did it transition from hostile to hospitable? If scientists can figure that out, they'll be better able to understand exoplanets and their atmospheres. Image Credit: Tohoku University

Will we ever understand how life got started on Earth? We’ve learned much about Earth’s long, multi-billion-year history, but a detailed understanding of how the planet’s atmospheric chemistry evolved still eludes us. At one time, Earth was atmospherically hostile, and its transition from that state to a planet teeming with life followed a complex path.

July 17, 2024July 17, 2024 by Evan Gough

Experimental Radar Technique Reveals the Composition of Titan’s Seas

This colorized mosaic from NASA's Cassini mission shows the most complete view yet of Titan's northern land of lakes and seas. Saturn's moon Titan is the only world in our solar system other than Earth that has stable liquid on its surface. The liquid in Titan's lakes and seas is mostly methane and ethane. New bistatic radar data from Cassini is revealing even more detail about Titan's hydrocarbon seas. Image Credit: NASA / JPL-Caltech / Agenzia Spaziale Italiana / USGS

The Cassini-Huygens mission to Saturn generated so much data that giving it a definitive value is impossible. It’s sufficient to say that the amount is vast and that multiple scientific instruments generated it. One of those instruments was a radar designed to see through Titan’s thick atmosphere and catch a scientific glimpse of the moon’s extraordinary surface.

Scientists are still making new discoveries with all this data.

May 15, 2024May 15, 2024 by Evan Gough

New Answers for Mars’ Methane Mystery

There's methane on Mars, but only in Gale Crater, and only sporadically. Image Credit:

Planetary scientists perk up whenever methane is mentioned. Methane is produced by living things on Earth, so it’s considered to be a potential biosignature elsewhere. In recent years, MSL Curiosity detected methane coming from the surface of Gale Crater on Mars. So far, nobody’s successfully explained where it’s coming from.

NASA scientists have some new ideas.

May 6, 2024September 16, 2024 by Evan Gough

What Can Early Earth Teach Us About the Search for Life?

This view of Earth from space is a fusion of science and art, drawing on data from multiple satellite missions and the talents of NASA scientists and graphic artists. This image originally appeared in the NASA Earth Observatory story Twin Blue Marbles. Image Credits: NASA images by Reto Stöckli, based on data from NASA and NOAA.

Earth is the only life-supporting planet we know of, so it’s tempting to use it as a standard in the search for life elsewhere. But the modern Earth can’t serve as a basis for evaluating exoplanets and their potential to support life. Earth’s atmosphere has changed radically over its 4.5 billion years.

A better way is to determine what biomarkers were present in Earth’s atmosphere at different stages in its evolution and judge other planets on that basis.

May 2, 2024May 2, 2024 by Evan Gough

Is the JWST Now an Interplanetary Meteorologist?

This artist’s concept shows what the hot gas-giant exoplanet WASP-43 b could look like. Image Credits: NASA, ESA, CSA, Ralf Crawford (STScI)

The JWST keeps one-upping itself. In the telescope’s latest act of outdoing itself, it examined a distant exoplanet to map its weather. The forecast?

An unending, blistering inferno driven by ceaseless supersonic winds.

April 29, 2024April 29, 2024 by Brian Koberlein

A Cold Brown Dwarf is Belching Methane Into Space

This artist concept portrays the brown dwarf W1935. Credit: NASA, ESA, CSA, Leah Hustak (STScI)

Brown dwarfs span the line between planets and stars. By definition, a star must be massive enough for hydrogen fusion to occur within its core. This puts the minimum mass of a star around 80 Jupiters. Planets, even large gas giants like Jupiter, only produce heat through gravitational collapse or radioactive decay, which is true for worlds up to about 13 Jovian masses. Above that, deuterium can undergo fusion. Brown dwarfs lay between these two extremes. The smallest brown dwarfs resemble gas planets with surface temperatures similar to Jupiter. The largest brown dwarfs have surface temperatures around 3,000 K and look essentially like stars.

March 5, 2024March 5, 2024 by Evan Gough

The LIFE Telescope Passed its First Test: It Detected Biosignatures on Earth.

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

We know that there are thousands of exoplanets out there, with many millions more waiting to be discovered. But the vast majority of exoplanets are simply uninhabitable. For the few that may be habitable, we can only determine if they are by examining their atmospheres. LIFE, the Large Interferometer for Exoplanets, can help.

January 29, 2024January 29, 2024 by Evan Gough

Another Explanation for K2-18b? A Gas-Rich Mini-Neptune with No Habitable Surface

Artist depiction of the mini-Neptune K2-18 b. Credit: NASA, CSA, ESA, J. Olmstead (STScI), N. Madhusudhan (Cambridge University)

Exoplanet K2-18b is garnering a lot of attention. James Webb Space Telescope spectroscopy shows it has carbon and methane in its atmosphere. Those results, along with other observations, suggest the planet could be a long-hypothesized ‘Hycean World.’ But new research counters that.

Instead, the planet could be a gaseous mini-Neptune.

November 30, 2023November 30, 2023 by Evan Gough

Could Life Exist in Molecular Clouds?

This image from the APEX telescope, of part of the Taurus Molecular Cloud, shows a sinuous filament of cosmic dust more than ten light-years long. Could life exist in molecular clouds like this one? Credit: ESO/APEX (MPIfR/ESO/OSO)/A. Hacar et al./Digitized Sky Survey 2. Acknowledgment: Davide De Martin.

Our search for life beyond Earth is still in its infancy. We’re focused on Mars and, to a lesser extent, ocean moons like Jupiter’s Europa and Saturn’s Enceladus. Should we extend our search to cover more unlikely places like molecular clouds?

November 22, 2023November 22, 2023 by Evan Gough

Wow. JWST Just Found Methane in an Exoplanet Atmosphere

This artist’s rendering shows the warm exoplanet WASP-80 b. When viewed with human eyes, the colour may appear bluish due to the lack of high-altitude clouds and the presence of atmospheric methane identified by NASA’s James Webb Space Telescope. That makes it similar to the planets Uranus and Neptune in our own solar system. Image credit: NASA.

If there’s one chemical that causes excitement in the search for biosignatures on other worlds, it’s methane. It’s not a slam dunk because it has both biotic and abiotic sources. But finding it in an exoplanet’s atmosphere means that planet deserves a closer look.