NASA has recently observed a massive gully on Mars via images on the Mars Reconnaissance Orbiter (MRO). The gully was not spotted in three years, according to NASA officials.
The gully shows a deep depression on the Red Planet on 25 May 2013, but the mark was not present in HiRISE photos of the region taken on 05 November 2010, according to the U.S. space agency.
However, NASA is working to find out the origin of the massive gully on the surface of the Red Planet. They are also to determine the exact time of the gully's formation.
The US space agency says that they are not considering the possibility of water involved in the formation of gully and instead suspect the role of carbon dioxide in the gully formation. Since long, NASA has observed carbon dioxide playing the role of water on the Red Planet.
"The dates of the images are more than a full Martian year apart, so the observations did not pin down the Martian season of the activity at this site. [However,] before-and-after HiRISE pairs of similar activity at other sites demonstrate that this type of activity generally occurs in winter, at temperatures so cold that carbon dioxide, rather than water, is likely to play the key role." Space Reporter quoted NASA officials.
This also supports the fact that some kind of liquid water may have flown in some areas in the planet Mars. If water does exist across the Red Planet's surface, it is likely that the planet can also host life on it.
However, it is not clear if NASA will shift its Curiosity Rover in search for similar regions close to Mount Sharp, where the hunt for signs of water is currently going on.