by The highest volcanoes in the solar system are located in the Equatorial region of Mars, which – as well as standing as high as three Mount Everest in some cases – discovered an unexpected frost phenomenon, according to a new study.
The largest – Olympus Mons – is 16 miles (26 kilometers) high and a whopping 374 miles (602 kilometers) in diameter, making it about 100 times larger than the world’s largest volcano, Mauna Loa , in Hawaii. In fact, the entire Hawaiian island chain would fit inside the Martian volcano, according to NASA.
On top of these giants are large calderas – bowl-shaped depressions caused by the collapse of the top of the volcano after an intense eruption.
The size of the calderas – up to 75 miles (121 kilometers) across – creates a special micro-climate within them. Using cameras fitted to probes orbiting Mars, researchers observed morning frost forming within the calderas for the first time.
“The deposits are forming on the floor of the caldera, but we also see a bit of frost on its rim. We also confirmed that it is likely ice and water,” said Adomas Valantinas, a postdoctoral researcher at Brown University who made the discovery as a doctoral student at the University of Bern, Switzerland, and lead author of the study.
“It’s significant because it shows us that Mars is a dynamic planet, but also that water can be found almost everywhere on the Martian surface.”
5,000 images
The team of more than two dozen researchers saw frost in four volcanoes: Arsia Mons, Ascraeus Mons and Ceraunius Tholus, as well as Olympus Mons, according to the study published Monday in the journal Nature Geoscience.
The deposits are extremely thin – only the first part of a millimeter thick, or one sixth of a human hair, according to Valantinas – but they are spread over such a large surface area that they are full of water. “Based on rough estimates, it’s about 150,000 metric tons of water ice, equivalent to 60 Olympic swimming pools,” he said.
To look at the deposits, the team first looked at around 5,000 images taken by CaSSIS – the University of Bern’s Stereo Color and Surface Imaging System – a high-definition camera that has been taking photos of Mars since 2018. It is among the -instruments on board the ExoMars Trace Gas Orbiter, a spacecraft launched in 2016 as a collaboration between the European Space Agency and the Russian space agency Roscosmos.
“This is also the first discovery from CaSSIS, which is very exciting,” Valantinas said.
The team confirmed its observations with two other instruments: NOMAD, a spectrometer also on board the Trace Gas Orbiter, and HRSC, or high-resolution stereo camera, an older camera on board the ESA Mars Express orbiter, a spacecraft launched in 2003.
A serendipitous find
Valantinas says the discovery came with some serendipity, as he was initially looking for carbon dioxide frost but found none. The deposits have not been seen until now because they only form in the early morning and in the cooler months, making the observation window narrow.
However, it is unlikely that human astronauts could one day remove the frost on Mars. “It would be quite difficult, because although it is a large deposit it is also very thin and short-lived, which means that it is only there during the night and early morning, then it sublimates back into the atmosphere, ” said Valantinas.
The volcanoes are near the equator of Mars, the hottest area on the planet, which makes the discovery of water particularly interesting, Valantinas said.
“Mars is a desert planet, but there is water ice in the polar caps, and there is water ice in the midlatitudes. Now we also have frost water in the equatorial regions, and equatorial regions are generally quite dry. So this was unexpected,” he said.
He also said that these volcanoes may have had glaciers when Mars had a thicker atmosphere and a different climate in the past. The team now wants to expand the search for frost to more than a dozen named volcanoes on Mars.
A remarkable achievement
If humans are ever going to explore the red planet, we will need to know where the water is, so the Martian water cycle is an important area of study, said John Bridges, professor of planetary sciences at the University of Leicester. in the United States. Kingdom, who were not involved in the study.
“This paper is a great use of the CaSSIS camera on the ExoMars Trace Gas Orbiter, which provides both visible color and infrared light visible from the Martian surface,” Bridges said, calling the results a “significant achievement.”
In addition, the water cycle on Mars is not as active as it was billions of years ago, so it is challenging to measure how water moves around the surface, notes J. Taylor Perron, the Cecil and Ida Green Professor of Earth, Atmospheric and Planetary Sciences at the Massachusetts Institute of Technology. Perron was also not affiliated with the new research.
“If the frost on these volcanoes is confirmed to be water (rather than carbon dioxide), it would be a big surprise,” he said.
Everywhere on the surface of Mars is cold and dry, Perron said, but the area around the equator is drier and less cold than the poles, so it’s one of the last places you’d expect water frost. It would also raise the question, he said, of where the water vapor that creates the frost comes from — from the volcanoes, even though they are dormant, or much further away, like the polar ice caps.
For more CNN news and newsletters create an account at CNN.com
