Liquid water lake on Mars
 

A liquid water 'lake' ha been discovered on Mars, under the planet's southern polar icecap

https://www.bbc.com/news/science-environment-44952710

It has been found before (September 2015)

https://www.bbc.co.uk/news/science-environment-34379284

but this is the first sign of a present-day major accumulation of liquid water.

Could this suggest the sun is getting hotter/closer? Or that orbits are changing?

Human theories of water on Mars have existed for long time. In 1877, Italian astronomer Giovanni Schiaparelli even claimed to have seen canals on Mars.

It's just surprising to me that even 18 years after we've been dropping actual landers with cameras onto Mars' surface... we still have "theories" about water on Mars.

Time for manned missions, as soon as possible.

According to wikipedia:
"Among Schiaparelli's contributions are his telescopic observations of Mars. In his initial observations, he named the "seas" and "continents" of Mars. During the planet's "Great Opposition" of 1877, he observed a dense network of linear structures on the surface of Mars which he called "canali" in Italian, meaning "channels" but the term was mistranslated into English as "canals".
While the term "canals" indicates an artificial construction, the term "channels" connotes that the observed features were natural configurations of the planetary surface. From the incorrect translation into the term "canals", various assumptions were made about life on Mars;"

The word "canale" in Italian can refer to both natural channels (like the English Channel), and artificial canals (like those in Amsterdam, Annecy, Rotterdam or Venice)

https://it.wikipedia.org/wiki/Canale_(oceanografia)

https://it.wikipedia.org/wiki/Canale_artificiale

Basically:

• The lake was discovered by a radar satellite and the math that followed.
• It took three years of radar research near Mars' south pole to make this discovery.
• The liquid is salty enough to be extremely dangerous to humans and other life forms, but even so has all the necessities for possibly containing microbial life. It's more like a sludgy brine.

The sun or orbits have absolutely nothing to do with it since its nearly a mile underground and has probably been there for thousands of years, if not more.

I know, I'm Italian :)

The inner nerd child in me would be screaming with delight since I was into astronomy in my younger years.

A PBS documentary was shown some years ago that discussed the 'recent' discovery of high levels of salinity within an area that was deep enough to support an vast ancient ocean when both the Spirit and Opportunity rovers rolled across the Martian surface back in '04.

However, I did wonder of all water on Mars either flowing underground or locked up in an icecap, was safe for anything outside of Martian biology. Thanks for the info, Utrommaniac.

Wait. Since when is salt extremely dangerous to humans? We eat salt every day after all. Maybe they mean you can't drink that martian water as it is but, you know, isn't it pretty obvious?

It's dangerous when you have too much.

Everything is dangerous when you have too much, even clean water, since that severely dilutes the salt in your body to a deadly level. Or too little.

Oxygen is important to us, but even too much of that can be deadly.

In the case of the salinity of this Martian lake, you don't even want to so much as lick the water.