The space agency will gather a host of experts to its headquarters in Washington for a briefing where it promises to announce it has solved a huge mystery surrounding the Red Planet.
NASA's previous announcements have revealed groundbreaking findings, such as that in July of the discovery of Earth-life planet Kepler-452b, outside of the Solar System.
Experts at this event include Jim Green, the director of planetary science at NASA and Michael Meyer, lead scientist for the Mars Exploration Program.
One theory is they will announce microbial life on the planet but a more likely scenario is evidence of flowing water.
Those hopes have been given a boost by the attendance of scientist Lujendra Ojha, of the Georgia Institute of Technology in Atlanta, at the Nasa announcement.
He first came up with the theory that Mars has liquid salt water flowing through it during warmer months.