NASA has revealed a totally unexpected discovery on the surface of Mars, and it proves just how little we know about the red planet.

Scientists have found ‘water’ at the Martian Equator and the discovery has baffled researchers who are unable to figure out how it could have been preserved there.

After reanalyzing Mars images in NASA files, a team of scientists led by Jack Wilson of Johns Hopkins University in the United States has discovered evidence of significant hydration – possibly frozen water – near the Martian equator, a place where it should not exist.

In their study, researchers re-processed data collected between 2002 and 2009 by the neutron spectrometer installed aboard the Mars Odyssey spacecraft. The equipment considerably improved the resolution of the images, reducing the blur and obtaining a clearer image of the Martian surface.

Re-analysis of 2002-2009 data from a hydrogen-finding instrument on NASA’s Mars Odyssey orbiter increased the resolution of maps of hydrogen abundance. The reprocessed data (lower map) shows more “water-equivalent hydrogen” (darker blue) in some parts of this equatorial region of Mars. Credits: NASA/JPL-Caltech/Univ. of Arizona

“It was as if we’d cut the spacecraft’s orbital altitude in half, and it gave us a much better view of what’s happening on the surface,” explained Jack Wilson, the study’s principal investigator.

After performing these tasks, scientists unexpectedly discovered large amounts of hydrogen – which at high latitudes is a sign of buried ice – in the area of the Medusae Fossae formation.

But science cannot explain how frost could be preserved in that area, and the main theory is that a mixture of ice and dust from the polar areas may have cycled through the atmosphere when the axial tilt of Mars was larger than at present.

However, Wilson points out that that should have happened billions of years ago and that any fraction of ice deposited in the area should have disappeared long ago.

The researcher points out that the finding could perhaps be explained: “in terms of extensive deposits of hydrated salts, but it is also difficult to explain how they came to be in formation.”

“For now it remains a mystery worthy of further study, and Mars continues to amaze us,” Wilson concluded.

NASA points out that the possible presence of freezing water near the equator is of great interest for future expeditions to Mars, as astronauts could use it as a source of water or for the production of hydrogen fuel.

However, most importantly the presence of water along the planet’s warmest latitudes would also open to door for long-term colonization, perhaps even some limited agriculture.

The discovery comes as a surprise to many, but as something you’d expect to others.

It is well known that Mars once had more water than the Arctic Ocean for a period of more than 1.5 billion years. Over the last 3.7 billion years, our neighboring planet lost around 87 percent of its water, which is why it appears barren and dry.

Experts have determined that during Mars’ Noachian period—between 4.1 and 3.7 billion years ago—the red planet had enough water to cover the entire surface in a liquid layer around 140 meters deep.