Video Pools of salty liquid surround a larger lake of water hidden beneath a thick crust of ice below the Martian south pole. That's according to findings published in Nature Astronomy on Monday.
Astronomers analyzing radar data from the European Space Agency’s Mars Express spacecraft detected a bright layer buried 1.5km (1 mile) below the southern polar ice caps with properties that matched liquid water. A central body of water, a lake measuring 20×30km (12x19 miles), was revealed in 2018. Better analytics and observations now show three more liquid pools surrounding this body, suggesting Mars may be more water-rich than first thought.
Using the Mars Advanced Radar for Subsurface and Ionosphere Sounding instrument (MARSIS) aboard the probe, the boffins spotted the pools – as shown in the video below – around the central lake in a region named Ultimi Scopuli.
“Our results strengthen the claim of the detection of a liquid water body at Ultimi Scopuli and indicate the presence of other wet areas nearby,” the team's published paper stated.
Subglacial lakes are found beneath Earth’s south pole, too. The largest one, known as Lake Vostok, is 250x50km (155x31 miles) and lies nearly 3,500 metres under Antarctica. For the pools on Mars to remain as a liquid, the researchers reckon it must have a high concentration of salt which lowers its freezing point.
It's not impossible for basic forms of life to exist in such circumstances, Earth has plenty of extremophiles of its own; you'll need a raggle-taggle band of deep-core drillers to visit Mars and burrow down to find out for sure.
Too hot to handle
Here's a planet where life has pretty much been ruled out, though.
ESA says Cheops – its Characterising Exoplanet Satellite that was launched last year – has made its first discovery out in space: an ultra-hot Jupiter-like world, dubbed WASP-189b, which has a surface temperature of 3,127 degrees Celsius. It’s so hot, iron would instantly melt and evaporate away on the surface, and it is circling a particularly fiery sun.
“Only a handful of planets are known to exist around stars this hot, and this system is by far the brightest,” said Monika Lendl, first author of a study into the exoplanet, published in the Astronomy & Astrophysics journal, and a senior research associate at the University of Geneva. “WASP-189b is also the brightest hot Jupiter that we can observe as it passes in front of or behind its star, making the whole system really intriguing.”
“The system is comparatively young, only 730 million years, whereas most exoplanet systems that we know of are at least 1,000 million years old,” Lendl told El Reg. “A hot star like the host star of this planet evolves fast, and when it will, it will swell up and swallow WASP-189b.” ®