An amateur astronomer in West Chester, Penn. took a picture of a curious Martian cloud several nights ago that has the community of Mars observers abuzz. Wayne Jaeschke photographed Mars on the evening of March 19 with a 14-inch telescope and noticed the plume after processing his images.
It struck him as odd the way it stood so high off the planet’s limb, so he shared it with other Mars watchers in the online Mars Group. He also made a cool 5-frame animation of the feature you can view HERE.
Once word got out, confirmation of the cloud came in from other amateur astronomers who had photographed it both before and after the 19th. No one is certain of the cloud’s nature yet, but it could be made of ice crystals or perhaps even dust whirled into the Martian atmosphere. Its altitude is estimated at 60 miles or higher. See more photos HERE.
Mars is no stranger to clouds, though not the puffy cumulus or heavy rolls of stratus we’re familiar with on the home planet. Mars’ atmosphere is composed mostly of carbon dioxide and extremely thin. You’d have to jump in a spy plane and travel to an altitude of 115,000 feet (21.7 miles) in Earth’s atmosphere to approach the rarity of Martian air.
That doesn’t stop Mars from having clouds. Seasonal carbon dioxide and water ice vaporizing from the Martian polar caps provide the necessary materials to build clouds, and the atmosphere is sown with the dust to seed their formation.
Some clouds are made of water ice, like the familiar afternoon clouds that form around the planet’s high elevation extinct volcanoes like Olympus Mons, while others are composed of dry ice crystals. They’re mostly wispy, much like the ice crystal clouds called cirrus or “mares’ tails”, and they drift across the planet’s pink sky. They’re propelled by winds just like Earth’s clouds.
When Mars experiences strong dust storms, orange clouds of dust billow up above its surface that are easily visible in mid-sized telescopes. Occasionally these clouds can become so widespread that they literally blanket the planet, blocking its surface from view for a time.
This wouldn’t be the first time a cloud reached high enough to catch the sunlight and stand out above Mars. Back on May 17, 1997, the Hubble Space Telescope photographed something similar poking beyond the Martian terminator (border between day and night).
In the photo at right, the other white patches along the left side of the planet are additional clouds and hazes.
No one to my knowledge has seen the new cloud visually yet, but observers have been and will be seeking it out in the coming nights. The plume appears to be a very low contrast feature, requiring excellent observing skills, a fair-sized telescope and good optics.
If you’d like to make an attempt, it’s located just south of the dark feature Mare Cimmerium at Martian latitude 44 degrees S, 190 E. I’ll update with new photos in the coming days provided the cloud’s still there. Perhaps NASA will even get a picture of it with the orbiting Mars Reconnaissance Orbiter. Speaking of which, here’s a recent photo taken by the spacecraft of thin clouds over ice-covered dunes. Should we ever establish a base on the planet in the future, there will definitely be a need for a Martian meteorologist.