Atmosphere Archives

January 5, 2024January 6, 2024 by Evan Gough

GJ 367b is Another Dead World Orbiting a Red Dwarf

This artist's concept illustrates a red dwarf star surrounded by exoplanets. Credit: NASA/JPL-Caltech

Red dwarf exoplanet habitability is a hot topic in space science. These small dim stars host lots of exoplanets, including small rocky ones the size of Earth. But the little stars emit extremely powerful flares that can damage and strip away atmospheres.

If we’re ever going to understand red dwarf habitability, we need to understand the atmospheres of the exoplanets that orbit them.

December 18, 2023December 18, 2023 by Mark Thompson

Millions of Satellites Could Have a Profound Effect on the Earth’s Ionosphere

Mega-constellations of satellites. Credit: ESA-Science Office

Hardly a day goes by where a story hits the headlines about our abuse of the Earth’s precious environment be that the atmosphere or the oceans, forests or desert. When it comes to the atmosphere we all tend to immediately turn our attention to pollution, to gasses being released and disturbing the delicate balance. Yet a paper recently published points to a new demon, megaconstellations of satellites damaging the ionosphere – the ionised part of the upper atmosphere.

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.

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.

November 16, 2023November 16, 2023 by Evan Gough

Take a Plunge Into the Ice Giants

The unique atmospheric compositions of ‘ice giant’ planets Uranus and Neptune were recreated to simulate a plunge deep within them. These simulations are part of preparation for eventual atmospheric probes the ESA intends to send. Image Credit: University of Stuttgart’s High Enthalpy Flow Diagnostics Group

Our Solar System’s ice giants, Uranus and Neptune, have been largely left out of the planetary probe game. While all of the other planets—including even the demoted Pluto—have been the subjects of dedicated missions, the ice giants have not. In fact, the only spacecraft to ever even fly by Uranus and Neptune was Voyager 2 in the late 1980s.

November 16, 2023November 16, 2023 by Evan Gough

Life Might Be Easiest to Find on Planets that Match an Earlier Earth

Artist's impression of the "pale orange dot" - what early Earth would have looked like. Credit: NASA/Goddard Space Flight Center/Francis Reddy

We’re inching closer and closer to reliably detecting biosignatures on distant planets. Much of the focus is on determining which chemicals indicate life’s presence.

But life can also create free energy in a system, and excess energy can create chemical disequilibrium. That’s what happened on Earth when life got going. Could chemical disequilibrium be a biosignature?

October 17, 2023October 17, 2023 by Evan Gough

Spaceflight is Polluting the Atmosphere with Metal

NASA’s Space Launch System rocket carrying the Orion spacecraft launches on the Artemis I flight test, Wednesday, Nov. 16, 2022. Credit: NASA/Joel Kowsky

Humans can’t seem to interact with the environment at all without fouling it in some way. From plastic bags in the ocean’s deepest regions to soot on Himalayan glaciers, our waste is finding its way into Earth’s most difficult-to-reach places.

Now, we can add metals in the stratosphere to this ignominious list.

September 28, 2023September 28, 2023 by Evan Gough

Is it Life, or is it Volcanoes?

This artist's illustration shows an exoplanet with active volcanoes. But from a great distance we can't see the volcanoes, only the effect they have on their atmospheres, and that can muddy the waters when it comes to biosignatures. Image Credit: NASA’s Goddard Space Flight Center/Chris Smith (KRBwyle)

Astronomers are working hard to understand biosignatures and how they indicate life’s presence on an exoplanet. But each planet we encounter is a unique puzzle. When it comes to planetary atmospheres, carbon is a big piece of the puzzle because it has a powerful effect on climate and biogeochemistry. If scientists can figure out how and where a planet’s carbon comes from and how it behaves in the atmosphere, they’ve made progress in solving the puzzle.

But one of the problems with carbon in exoplanet atmospheres is that it can send mixed signals.

September 15, 2023September 15, 2023 by Evan Gough

Engineers Want to Make Methanol by Pulling Carbon Right Out of the Air

Researchers at Western Virginia University are working on a method of extracting carbon out of exhausted air from office buildings and using it to make methanol. Image Credit: WVU Illustration/Savanna Leech

Methanol is one of our most extensively used raw materials. It’s used as a solvent, a pesticide, and in combination with other chemicals in the manufacture of plastic, clothing, plywood, and in pharmaceuticals and agrochemicals.

It’s also used as a fuel.

July 29, 2023July 29, 2023 by Carolyn Collins Petersen

Astronomers are Watching a Planet Get its Atmosphere Blasted Away into Space

This artist's illustration shows a planet (dark silhouette) passing in front of the red dwarf star AU Microscopii. The planet is so close to the eruptive star a ferocious blast of stellar wind and blistering ultraviolet radiation is heating the planet's hydrogen atmosphere, causing it to escape into space. The illustration is based on measurements made by the Hubble Space Telescope. Credits: NASA, ESA, and Joseph Olmsted (STScI)

What do you get when a hot young world orbits a wildly unstable young red dwarf? For AU Microsopii b, the answer is: flares from the star tearing away the atmosphere. That catastrophic loss happens in fits and starts, “hiccuping” out its atmosphere at one point and then losing practically none the next.