Astronomers have discovered a smiley-face-shaped structure on Mars – and it could be more than just a planetary quirk.
Researchers believe that it may be harboring signs of past life on the Red Planet.
This grinning formation is made up of a pair of crater eyes and rings of ancient salt deposits.
These deposits are the remains of an ancient body of water that dried up long ago, leaving behind this emoji-like remnant that is only visible when viewed with an infrared camera.
The European Space Agency (ESA) – which snapped the photo – said: ‘These deposits, remnants of ancient water bodies, could indicate habitable zones from billions of years ago.’
The European Space Agency snapped this photo of a smiley-face-shaped salt deposit on Mars that could harbor evidence of ancient alien life on the Red Planet
Scientists aren’t sure exactly how big the smiley-face is, but it’s one of 965 other salt deposits that have recently been catalogued on Mars’ surface, which range in size from 1,000 to 10,000 feet wide.
Salt deposits are accumulations of salt – or chloride – found on a planetary surface. On Mars, they are the remnants of ancient bodies of water that dried up when the planet underwent a major climatic shift eons ago.
Before the last puddles of Mars’ liquid water disappeared, they may have been a ‘haven’ for microbial life, according to the ESA.
These puddles would have been extremely salty, and thus the remains of microbes that once lived in them may still be preserved to this day – hiding in deposits like this smiley face.
The ESA captured this image using their ExoMars Trace Gas Orbiter, which has been measuring the levels of methane and other gases in Mars’ atmosphere since 2016 to help scientists understand possible biological or geological activity on the Red Planet.
Normally, salt deposits on Mars’ surface are invisible.
But the orbiter’s infrared cameras allow us to see them glowing pink or violet – revealing the smiley-face.
The photo was published as part of a study in the journal Scientific Data.
These salt deposits are typically invisible, but the infrared cameras on the ESA’s ExoMars Trace Gas Orbiter allow us to see them glowing pink or violet
As Mars’ liquid water disappeared, the last salty puddles could have harbored surviving microbial life, and their remains could be preserved in the resulting salt deposits
The research team, led by scientists from the University of Bern in Sweden, used images taken by the orbiter to create the most robust catalog of Mars’ chloride salt deposits to-date.
The new catalog contains data for nearly 1,000 different deposits located all across the planet’s surface.
These deposits paint a picture of ancient Mars that is very different than the red desert planet we know today. Billions of years ago, Mars hosted bodies of liquid water.
‘In the distant past, water formed magnificent landforms such as riverbeds, channels, and deltas on the Red Planet,’ said planetary scientist and study lead author Valentin Bickel in an ESA statement.
But studies suggest that sometime between three billion and two billion years ago, severe climate change caused these bodies of water to dry up.
That extreme climatic shift was likely triggered by the loss of Mars’ magnetic field, which allowed solar wind to erode the atmosphere and caused liquid water to freeze, evaporate or become trapped within the planet’s surface.
Now, salt deposits are some of the only evidence we have of Mars’ ancient water bodies.
What’s more, studying them could reveal clues about ancient microbial life that once lived in the planet’s liquid water, according to the study.
‘The new data has important implications for our understanding of the distribution of water on early Mars, as well as its past climate and habitability,’ Bickel said.
While there is no conclusive evidence pointing to past or present life on Mars, this study adds to a growing body of research that has reignited the search for microbes on the Red Planet.