2024-09-06 19:35:30
The study updates the 2007 observations with more recent radar data also recorded by the Mars Express spacecraft. The signals are similar to those of Mars’ polar ice caps, which contain water ice. But scientists weren’t sure how far back they were. Medusae Fossae until you realize its depth.
It can’t be anything else
Map of Medusae Fossae water ice deposits on Mars
The deposits are covered by a layer of dust and ash several hundred metres thick. If it were all one huge pile of dust, it would compact under its own weight. But the material beneath is not so dense.
“When we modelled how different materials other than ice would behave, nothing reproduced the properties of the Medusae Fossae formation: we needed ice,” explains Andrea Cicchetti of Italy’s National Institute for Astrophysics.
There is so much ice, in fact, that if it were to melt it would cover the entire planet with a blanket at least 1.5 metres deep. Or put another way, there is enough water to fill the Earth’s Red Sea.
It is impossible for all that water to have formed in Mars’ current climate. We know that before it was an arid world, the planet had oceans and rivers. Now we must solve a new mystery: when and how the huge reservoir of water beneath Medusae Fossae was formed.