Scientists have claimed that lakes beneath the south pole of Mars may not be real. Researchers had in 2018 claimed to make a surprising discovery on the Red Planet. They detected signals from a radar instrument to reveal a liquid subsurface lake on the planet’s South Pole. The discovery was made during a detailed analysis of data obtained from the Mars Express orbiter. It is a space exploration mission by the European Space Agency. It was launched in 2003. However, NASA scientists and Arizona State University researchers have now said that subsurface lakes may not really be lakes. They too detected similar radar reflections near the South Pole. They said that many fall in regions that are too cold and make it difficult for water to stay in its original form.
Scientists said that loss of energy is reported in radar waves when they travel through a material. Therefore, the reflections should be less bright when coming from deep than those from a surface. The latest study said that there could be other reasons for bright subsurface reflections. It said that the 2018 studies claimed that a liquid water component resulted in bright reflections. Notably, when water is in its real form, which is liquid, it appears bright to radar. The region where radar detected liquid water is called South Polar Layered Deposits. Scientists said that temperatures in these areas are estimated to be around minus 63 degrees Celsius. They said that water would be frozen at this temperature even if salty minerals are present.
The Jet Propulsion Laboratory of NASA said that scientists detected signals more widespread than what was reported in the original paper. The study said that these radar reflections could be indicative of something else in the region. Notably, the Mars Express is the second-longest-surviving orbiter. It still provides data related to Mars’ atmosphere, surface, and subsurface. The orbiter uses a radar sounder to study the composition of Mars’ subsurface. NASA’s Mars Odyssey is the longest surviving orbiter. It is still active since its launch in 2001. Several countries have sent orbiter missions to Mars. But the US and China are the only two countries that have landed rovers on the Red Planet. While NASA has sent several robotic missions, China achieved the feat in May 2021.
