Atmosphere Archives

June 28, 2024June 28, 2024 by Evan Gough

Could We Detect an Alien Civilization Trying to Warm Their Planet?

This artist's illustration shows a hypothetical Earth-like inhabited planet being terraformed with artificial greenhouse gases. We could detect these chemicals with infrared spectroscopy. Image Credit: Sohail Wasif, UC Riverside/Schwieterman et al. 2024

Humanity is facing an atmospheric threat of our own device, and our internecine squabbles are hampering our ability to neutralize that threat. But if we last long enough, the reverse situation will arise. Our climate will cool, and we’ll need to figure out how to warm it up. If that day ever arises, we should be organized enough to meet the challenge.

If there are other civilizations out there in the galaxy, one may already be facing a cooling climate or an ice age. Could we detect the greenhouse chemicals they would be purposefully emitting into their atmosphere in an attempt to warm their planet?

June 18, 2024June 18, 2024 by Evan Gough

Earth’s Atmosphere is Our Best Defence Against Nearby Supernovae

Artist's impression of a Type II supernova explosion. These supernova produce gamma rays and powerful ionizing radiation that's hazardous to life. Credit: ESO

Earth’s protective atmosphere has sheltered life for billions of years, creating a haven where evolution produced complex lifeforms like us. The ozone layer plays a critical role in shielding the biosphere from deadly UV radiation. It blocks 99% of the Sun’s powerful UV output. Earth’s magnetosphere also shelters us.

But the Sun is relatively tame. How effective are the ozone and the magnetosphere at protecting us from powerful supernova explosions?

June 17, 2024June 17, 2024 by Evan Gough

The Great Red Spot Probably Formed in the Early 1800s

"Great Red Spot from P7 Flyover". Credit: NASA / SwRI / MSSS / Jason Major © public domain

Jupiter’s Great Red Spot (GRS) is one of the Solar System’s defining features. It’s a massive storm that astronomers have observed since the 1600s. However, its date of formation and longevity are up for debate. Have we been seeing the same phenomenon all this time?

June 13, 2024June 13, 2024 by Evan Gough

Sulphur Makes A Surprise Appearance in this Exoplanet’s Atmosphere

This artist's illustration shows the Neptune-like exoplanet GJ 3470b, which has an atmosphere rich in sulphur. The planet's atmosphere holds clues to how it and other similar planets formed. Image Credit: Department of Astronomy, UW–Madison

At our current level of knowledge, many exoplanet findings take us by surprise. The only atmospheric chemistry we can see with clarity is Earth’s, and we still have many unanswered questions about how our planet and its atmosphere developed. With Earth as our primary reference point, many things about exoplanet atmospheres seem puzzling in comparison and generate excitement and deeper questions.

That’s what’s happened with GJ-3470 b, a Neptune-like exoplanet about 96 light-years away.

June 3, 2024June 3, 2024 by Evan Gough

Life Probably Played No Role in Mars’ Organic Matter

Color mosaic image of Mars, taken by the HRSC instrument aboard the ESA's Mars Express orbiter. Credit: ESA/DLR/FU Berlin (G. Michael)

The Martian surface shows ample evidence of its warm, watery past. Deltas, ancient lakebeds, and dry river channels are plentiful. When the Curiosity rover found organic matter in ancient sediments in the Jezero Crater paleolake, it was tempting to conclude that life created the matter.

However, new research suggests that non-living processes are responsible.

May 14, 2024May 14, 2024 by Evan Gough

TRAPPIST-1 Outer Planets Likely Have Water

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

The TRAPPIST-1 solar system generated a swell of interest when it was observed several years ago. In 2016, astronomers using the Transiting Planets and Planetesimals Small Telescope (TRAPPIST) at La Silla Observatory in Chile detected two rocky planets orbiting the red dwarf star, which took the name TRAPPIST-1. Then, in 2017, a deeper analysis found another five rocky planets.

It was a remarkable discovery, especially because up to four of them could be the right distance from the star to have liquid water.

May 3, 2024May 3, 2024 by Evan Gough

Did You Hear Webb Found Life on an Exoplanet? Not so Fast…

Artist rendering of the view on a Hycean world. The recent detection of a biosignature on the Hycean world K2-18b attracted a lot of attention. Image Credit: Shang-Min Tsai/UCR

The JWST is astronomers’ best tool for probing exoplanet atmospheres. Its capable instruments can dissect the light passing through a distant world’s atmosphere and determine its chemical components. Scientists are interested in everything the JWST finds, but when it finds something indicating the possibility of life it seizes everyone’s attention.

That’s what happened in September 2023, when the JWST found dimethyl sulphide (DMS) in the atmosphere of the exoplanet K2-18b.

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 8, 2024April 8, 2024 by Evan Gough

Measuring the Atmospheres of Other Worlds to See if There are Enough Nutrients for Life

A NASA graphic explaining how a telescope can measure an exoplanet atmosphere using spectroscopy. Courtesy: NASA/JPL-Caltech/Lizbeth B. De La Torre.

Life on Earth depends on six critical elements: Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorous, and Sulfur. These elements are referred to as CHNOPS, and along with several trace micronutrients and liquid water, they’re what life needs.

Scientists are getting a handle on detecting exoplanets that might be warm enough to have liquid water on their surfaces, habitability’s most basic signal. But now, they’re looking to up their game by finding CHNOPS in exoplanet atmospheres.

March 22, 2024March 22, 2024 by Evan Gough

Finding Atmospheres on Red Dwarf Planets Will Take Hundreds of Hours of Webb Time

This illustration shows what exoplanet K2-18 b could look like based on science data. NASA’s James Webb Space Telescope examined the exoplanet and revealed the presence of carbon-bearing molecules. The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b. But more extensive observations with the JWST are needed to understand its atmosphere with greater confidence. Image Credit: By Illustration: NASA, ESA, CSA, Joseph Olmsted (STScI)Science: Nikku Madhusudhan (IoA)

The JWST is enormously powerful. One of the reasons it was launched is to examine exoplanet atmospheres to determine their chemistry, something only a powerful telescope can do. But even the JWST needs time to wield that power effectively, especially when it comes to one of exoplanet science’s most important targets: rocky worlds orbiting red dwarfs.