A long and strange cloud has formed so many times on it Martian volcano that scientists have given up and named it.
Meet the elongated cloud of Arsia Mons, or AMEC. Its long and bright trail has become a familiar feature on the peak known as Arsia Mons, southeast of the most famous. Olympus Mons. Although the cloud comes and goes over the volcano, scientists say it is not made up of the volcano itself. And it’s timely: Scientists affiliated with Europe’s Mars Express orbiter hoped it would reappear in its annual cycle.
“We have been investigating this intriguing phenomenon and were expecting to see such a cloud at this time,” said Jorge Hernández-Bernal, Ph.D. candidate for the University of the Basque Country in Spain and main author of the current study, he said in a statement launched by the European Space Agency (ESA), which runs the spacecraft.
Photos: Views of the Red Planet from Europe’s Mars Express
“This elongated cloud forms each Martian year during this season around the southern solstice, and it repeats for 80 days or even more, “said Hernández-Bernal.” However, we still don’t know if the clouds are always that impressive. “
So far, scientists have trapped the cloud by marking up to 1,100 miles (1,800 kilometers), according to ESA. The tail-shaped structure is made of water ice, and despite its location on Arsia Mons, it is not formed by the volcano itself, the scientists said, but by the way that local winds interact with the topography.
And the elongated cloud of Arsia Mons not only comes, stays for a while and then dissipates. It forms and fades over the course of a few hours each local morning, then returns the next day. That makes the strange cloud difficult to study from orbit around the Red Planet.
But Mars Express is specially qualified to do so. He carries an instrument called the Visual monitoring camera, which can photograph an unusually wide swath of the planet in a single frame. And the spacecraft’s orbit lines up to bring Arsia Mons into view during the morning hours when the cloud is visible.
“The range of this large cloud cannot be seen if your camera only has a narrow field of view, or if you are only observing in the afternoon,” said Eleni Ravanis, a graduate trainee on the Visual Monitoring Camera team. the declaration. “Fortunately for Mars Express, the spacecraft’s highly elliptical orbit, coupled with the VMC instrument’s wide field of view, allows us to take pictures covering a wide area of the planet first thing in the morning. That means we can catch it. ! “
The scientists the last time you saw the tail-shaped cloud of Arsia Mons in September and October 2018. Right now, the days are the shortest of the year in the northern hemisphere of the red planet and the longest of the year in the southern hemisphere. Arsia Mons itself is located slightly south of the Martian equator and extends to an altitude of approximately 12 miles (20 km).
Scientists hope that by continuing to study the strange cloud, they can begin to understand how long it has been appearing and why it appears only in the morning.
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