But now, according to a paper published in the journal Science, the Mars Express spaceship has detected what appears to be an enormous lake, 20 kilometres (12 miles) across, around 1.5m (1 mile) beneath the water-and-carbon-dioxide ice of the planet’s south pole.
And today it has been announced that scientists have discovered large pools of liquid underneath the planet’s polar ice caps. “The problem is that this water is located 1.5km underneath the South Pole, so there is an terrible lot of ice to be drilled to before you reach this liquid water”, he added.
Given that the ghostly shadows of Mars’ watery past cover the planet, the existence of liquid water beneath its surface had always been suspected by scientists. While it was not the Mars anyone imagined, in many ways this increased the planet’s allure. When the team of scientists analyzed the data, they discovered a “very sharp change” in the signals, which resembled the signal of water hidden under the ice sheets of Antarctica and Greenland.
Lake beds like those explored by Nasa’s Curiosity rover show water was present on the surface of Mars in the past.
Discovery of water also means that the planet is less hostile for future life, if we colonise it. If life did arise from those early, cosy conditions, it could have moved underground as the surface cooled and dried. “That’s a fundamental aspect of astrobiology”, said Jim Green, chief scientist of NASA, who was not involved in the study.
Do you think liquid water under high pressure with dissolved salts would be hospitable to life? The device sends radar signals that pierce the ice at the planet’s surface, and measures how the “radio waves” spread and reflect back ‘to the probe’.
The measurements were taken over three years.
After analysing the results, a particularly bright 20km-wide spot was found, which was interpreted to be a stable body of liquid water, laden with salty, saturated sediments.
A massive underground lake has been detected for the first time on Mars, raising the possibility that more water – and maybe even life – exists there, global astronomers said Wednesday. The Mars water would have to have a similar make-up to actually be liquid.
“On Earth, nobody would be surprised by such a discovery”.
Do we need to go to Mars to find out what’s in this lake? SHARAD operates at different frequencies than MARSIS does, but it’s also created to pick up subsurface features.
Richard Zurek, the chief scientist in the Mars program office at NASA’s Jet Propulsion Laboratory in Pasadena, California, said the complex, nearly chaotic structure of the ice caps could affect the radar signals in unexpected ways. The discovery of the lake, more specifically, was based on information collected by the instrument between May 2012 and December 2015.
However, pure liquid water has never been found until now.
This is evident from life which is able to exist in Earth’s sub-freezing north and south poles, and Prof Orosei believes it will be a similar case on Mars.
The team used a radar instrument on an orbiting spacecraft to detect the body of water underneath Mars’s polar ice cap.