A cosmic grin has been discovered on the surface of Mars, sending a wave of excitement through the scientific community. This ‘smiley face,’ captured by the European Space Agency’s (ESA) ExoMars Trace Gas Orbiter, isn’t a playful prank of the universe but rather a remarkable glimpse into Mars’ ancient past. The emoticon-like structure, visible only under specific conditions, is the dried-up remains of a lake that existed billions of years ago, and it could hold clues to the existence of past life on the Red Planet.
The smiley face is formed by a ring of ancient chloride salt deposits, with two meteor-crater ‘eyes’ adding to the whimsical image. These deposits, usually blending seamlessly with the Martian landscape, stand out in infrared images thanks to their pink or violet appearance. This discovery was made as part of a larger study, published in the journal Scientific Data, where researchers compiled the first comprehensive catalog of chloride salt deposits on Mars using images from the ExoMars Orbiter. The team identified a staggering 965 different deposits spread across the alien world, each ranging in size from 1,000 to 10,000 feet wide.
The significance of these deposits lies in their potential to preserve evidence of ancient life. Researchers believe that the salty conditions created by shrinking Martian lakes could have provided a haven for microbial extremophiles, which may have thrived in the harsh environment. As these lakes eventually dried up, the remnants of these microbes, potentially preserved by the salt, could be waiting to be discovered.
Mars, once a vibrant world with lakes, rivers, and a shallow ocean, has undergone a dramatic transformation. Billions of years ago, the loss of its magnetic field led to the gradual stripping away of its atmosphere, causing the majority of its water to freeze or evaporate into space. The chloride salt deposits are remnants of this watery past, offering a tantalizing glimpse into Mars’ history. They also act as a powerful reminder of the planet’s potential to harbor life, past or present.
This exciting discovery comes at a time when scientists are revisiting the possibility of liquid water on Mars. Recent findings, including the detection of a vast hidden ocean beneath the planet’s surface and the discovery of water frost on Martian volcanoes, have reignited hope for finding evidence of life on the Red Planet. The ‘smiley face’ on Mars serves as a powerful symbol of the wonders waiting to be uncovered on this intriguing and enigmatic world.
