Atmosphere Archives

December 23, 2020December 23, 2020 by Evan Gough

If a Planet Has a Lot of Methane in its Atmosphere, Life is the Most Likely Cause

This artist’s impression shows the planet K2-18b, it’s host star and an accompanying planet in this system. K2-18b is now the only super-Earth exoplanet known to host both water and temperatures that could support life. UCL researchers used archive data from 2016 and 2017 captured by the NASA/ESA Hubble Space Telescope and developed open-source algorithms to analyse the starlight filtered through K2-18b’s atmosphere. The results revealed the molecular signature of water vapour, also indicating the presence of hydrogen and helium in the planet’s atmosphere.

The ultra-powerful James Webb Space Telescope will launch soon. Once it’s deployed, and in position at the Earth-Sun Lagrange Point 2, it’ll begin work. One of its jobs is to examine the atmospheres of exoplanets and look for biosignatures. It should be simple, right? Just scan the atmosphere until you find oxygen, then close your laptop and head to the pub: Fanfare, confetti, Nobel prize.

Of course, Universe Today readers know it’s more complicated than that. Much more complicated.

In fact, the presence of oxygen is not necessarily reliable. It’s methane that can send a stronger signal indicating the presence of life.

November 23, 2020November 23, 2020 by Evan Gough

Mars Might Have Lost its Water Quickly

This artist's concept depicts the early Martian environment (right) – believed to contain liquid water and a thicker atmosphere – versus the cold, dry environment seen at Mars today (left). Image Credit: NASA's Goddard Space Flight Center

Mars is an arid place, and aside from a tiny amount of water vapour in the atmosphere, all water exists as ice. But it wasn’t always this arid. Evidence of the planet’s past wet chapter dots the surface. Paleolakes like Jezero Crater, soon to be explored by NASA’s Perseverance Rover, provide stark evidence of Mars’ ancient past. But what happened to all that water?

It disappeared into space, of course. But when? And how quickly?

November 16, 2020November 16, 2020 by Matthew Cimone

There are Planets So Close to Their Stars That They Have Magma Oceans 100km Deep and Winds that Go 8000 km/h

Artist's impression of a lava world. The exoplanet K2-141b is so close to its host star that it likely has magma oceans and surface temperatures over 3000 degrees. It's possible water is mixed in with the magma. c. ESO

200 light years away, “super earth” exoplanet K2-141b orbits a star so closely that its “year” is only 7 hours long. Not its day…its YEAR! K2-141b orbits a mere million kilometers from the fiery surface of its star. Earth is 150 million km from our Sun. Even Mercury, the planet closest to our Sun, is never less than 47 million km. Standing on the surface of K2-141b you’d look up at an orange star that filled fifty degrees of the sky appearing a hundred times wider than our Sun appears in Earth’s sky. It would be a giant blazing orb so bright that its light shines two thirds of the way around the entire planet unlike Earth’s two day/night halves. Of course, the surface you’re standing on wouldn’t be much of a surface at all – it would be an ocean of liquid hot magma.

Artist’s impression of a close orbiting exoplanet around a star. c. ESO

October 22, 2020October 22, 2020 by Evan Gough

Astronomers Challenge Recent Findings About Venus. “No Statistically Significant Detection of Phosphine”

This artistic impression depicts Venus. Astronomers at MIT, Cardiff University, and elsewhere may have observed signs of life in the atmosphere of Venus. Credits:Image: ESO (European Space Organization)/M. Kornmesser & NASA/JPL/Caltech

In September, a team of scientists reported finding phosphine in the upper atmosphere of Venus. Phosphine can be a biomarker and is here on Earth. But it’s also present on Jupiter, where it’s produced abiotically. The discovery led to conjecture about what kind of life might survive in Venus’ atmosphere, continually producing the easily-degraded phosphine.

The authors of that study were circumspect about their own results, saying that they hope someone can determine a source for the phosphine, other than life.

Now a new study says that the original phosphine detection is not statistically significant.

October 15, 2020October 15, 2020 by Evan Gough

Astronomers Report They’ve Detected the Amino Acid Glycine in the Atmosphere of Venus

The planet Venus, as imaged by the Magellan mission. Credit: NASA/JPL

Does it feel like all eyes are on Venus these days? The discovery of the potential biomarker phosphine in the planet’s upper atmosphere last month garnered a lot of attention, as it should. There’s still some uncertainty around what the phosphine discovery means, though.

Now a team of researchers claims they’ve discovered the amino acid glycine in Venus’ atmosphere.

October 2, 2020October 2, 2020 by Evan Gough

Did Pioneer See Phosphine in the Clouds of Venus Decades Ago?

Artist’s rendition of a theoretical balloon probe in Venus Clouds c. T.Balint ESA

The discovery of phosphine in Venus’ atmosphere has generated a lot of interest. It has the potential to be a biosignature, though since the discovery, some researchers have thrown cold water on that idea.

But it looks, at least, like the discovery is real, and that one of NASA’s Pioneer spacecraft detected the elusive gas back in 1978. And though it’s not necessarily a biosignature, the authors of a new study think that we need to rethink the chemistry of Venus’ atmosphere.

September 30, 2020September 30, 2020 by Evan Gough

Maybe Volcanoes Could Explain the Phosphine in Venus’ Atmosphere

The detection of phosphine in Venus’ atmosphere was one of those quintessential moments in space science. It was an unexpected discovery, and when combined with our incomplete understanding of planetary science, and our wistful hopefulness around the discovery of life, the result was a potent mix that lit up internet headlines.

As always, some of the headlines were a bit of an over-reach. But that’s the way it goes.

At the heart of it all, there is compelling science. And the same, overarching question that keeps popping up: Are we alone?

September 16, 2020September 16, 2020 by Nancy Atkinson

Sunrises Across the Solar System

Saturn’s upper atmosphere. Processed using calibrated narrow-angle near-infrared (CB3) and ultraviolet (UV3) and wide-angle red, green, and violet filtered images of Saturn taken by Cassini on November 17 2007. NASA/JPL-Caltech/SSI/CICLOPS/Kevin M. Gill.

Scientists have learned a lot about the atmospheres on various worlds in our Solar System simply from planetary sunrises or sunsets. Sunlight streaming through the haze of an atmosphere can be separated into its component colors to create spectra, just as prisms do with sunlight. From the spectra, astronomers can interpret the measurements of light to reveal the chemical makeup of an atmosphere.

June 16, 2020June 16, 2020 by Evan Gough

Newborn Exoplanets can be Completely Stripped of Their Atmosphere by Stars

Artist's conception of exoplanet systems that could be observed by PLAnetary Transits and Oscillations of stars (PLATO), a European Space Agency telescope. Credit: ESA - C. Carreau

Newborn exoplanets can have a tough life. They may form an atmosphere, but that atmosphere can be doomed. Their stars can emit intense X-ray and UV radiation, stripping away those atmospheres and laying their surfaces bare.

A team of researchers from the Leibniz Institute for Astrophysics looked at a family of four newborn sibling planets, and tried to understand how their star strips away their gaseous envelopes.

May 28, 2020May 28, 2020 by Evan Gough

Extremely Hot Exoplanets Can Have Extreme Weather, Like Clouds of Aluminum Oxide and Titanium Rain

Thi illustration of a Hot Jupiter orbiting close to its star. Image Credit: ESA/ATG medialab, CC BY-SA 3.0 IGO

Thanks to the success of the Kepler mission, we know that there are multitudes of exoplanets of a type called “Hot Jupiters.” These are gas giants that orbit so close to their stars that they reach extremely high temperatures. They also have exotic atmospheres, and those atmospheres contain a lot of strangeness, like clouds made of aluminum oxide, and titanium rain.

A team of astronomers has created a cloud atlas for Hot Jupiters, detailing which type of clouds and atmospheres we’ll see when we observe different Hot Jupiters.