an international team of astronomers, manufacturing coming from the Orbiter Mars Express data, announced the return of the mysterious long cloud that hovers over an extinct volcano Arsia Mons (Mount Arsiya) on Mars.
returning Images of the clouds on its website published the European space Agency. In a release to them reported that they were made on July 17 and 19 by the visual monitoring camera (VMC), which is installed on the orbiting Mars Express. With its help scientists study orbit the Red planet for 16 years.
“We have been studying this intriguing phenomenon and expected to see just such a cloud form, explains the lead author of this ongoing research Jorge Hernandez-Bernal from University of the Basque Country (Spain). Is elongated cloud formed each Martian year after the southern solstice and occurs within 80 days or more. However, we do not yet know whether these clouds are so impressive.”
Scientists say that the mysterious long and very thin cloud appears again and again over 20 km of volcano Mountain Mons. Judging by the new images, the length of the cloud, which changes daily, can reach 1800 km.
In previous studies it was found that these clouds are composed of water ice. Despite his appearance and the fact that they hover over a volcano, their nature is not associated with volcanic activity. But, according to scientists, the volcano still plays its role: probably, these curious clouds are formed by air flows under the influence of the “leeward” side of the mountain.
a Martian day is slightly longer than earth’s day: it lasts 24 hours, 39 minutes and 35 seconds. A year on Mars is approximately 687 earth days. So the seasons last twice as long there than on our planet.
southern solstice on Mars is the time of year when the Sun is at the southernmost point of the Martian sky. On Earth a similar phenomenon is observed on December 21. It was during this period on Mars in the early morning, periodically grows very quickly and disappears a few hours later a passing cloud.
Most of the spacecraft in orbit around the red planet to observe its surface only during the day. Therefore, their cameras, as a rule, to fix a mysterious cloud can’t.
However, the Mars Express is in a privileged position – high elliptic orbit of the spacecraft in combination with the wide angle camera VMC allows you to take pictures, covering most of the planet in the early morning.
Astronomers hope that further studies will help to uncover the mystery of these clouds and to understand why they appear and disappear at regular intervals, and why are born only RAbut in the morning.
