A group of amateur astronomers who have been observing planet Mars has found what appears like two gigantic plumes extending from the Red Planet.
What this mysterious haze really is has baffled even professional astronomers who also have no clear idea of what this could be.
The extremely bright plume was initially spotted in March 2012 by Wayne Jaeschke, a member of the Association of Lunar and Planetary Observers (APOL). Unlike other Martian phenomena such as clouds and aurora that have only been seen up to 80 miles high, the plum extended about 12 miles into the Martian sky.
After the plume's initial appearance, it grew over the next few days and changed shape rapidly. It lasted for at least 11 days, after which a second plume emerged on the same region on April 6 and lasted for at least 10 days.
For their report on the phenomenon published in the journal Nature on Feb. 16, Jaeschke and colleagues looked at databases containing images of the Red Planet that were taken by the Hubble Space Telescope and amateur enthusiasts as early as 1995 and found only one thing similar to the plumes that appeared in March and April: an anomalous protrusion captured by the Hubble on May 17, 1997.
The researchers think that the plume could either be a large cloud or an unusually bright aurora that is a thousand times brighter than anything that was seen on Earth, but they are not certain as to how this could have formed given the current understanding on the Martian atmosphere.
Study researcher Agustin Sanchez-Lavega from the University of the Basque Country in Spain said that as an aurora, the plume would require a vast amount of energetic flux that calculations show are very unrealistic.
"For particles reflecting solar radiation, clouds of CO2 ice or H2O ice particles with an effective radius of 0.1 micrometers are favored over dust," the researchers wrote. "Alternatively, the plume could arise from auroral emission, of a brightness more than 1,000 times that of the Earth's aurora, over a region with a strong magnetic anomaly where aurorae have previously been detected."
The researchers said that they favor the idea that the plume was a large cloud since it formed in the cold mornings. Nonetheless, they noted that this also requires a large drop in temperature not foreseen in atmospheric models.
The scientists acknowledged that all of the explanations for the plume that they can think of challenge current understanding of the upper Martian atmosphere. They said that by publishing the paper, they hope that other scientists may also offer their explanations.