Scientists have found teh oldest evidence of the presence of hot water on Mars in the distant past of the planet. The revelation could prove that the Red Planet, despite its dry and desolate appearance today, may once have been able to support life. This is clear from a study published in the journal Science Advances.
The evidence was brought to Earth and sealed in the well-known Martian meteorite NWA7034, discovered in the Sahara desert in 2011. As of its black, highly polished appearance, the Martian rock is also known as “Black Beauty”.
With an estimated age of 2 billion years Black Beauty is the second oldest Martian meteorite ever discovered. The team at Curtin University in Australia found something even older: a 4.45 billion-year-old zircon grain that hides traces of fluids rich in water.
According to Aaron Cavosi from Curtin’s Faculty of Earth and planetary Sciences, this discovery will provide new opportunities to study the hydrothermal systems associated with the activity of volcanic magma that was once on Mars.
“Hydrothermal systems were essential for the development of life on Earth, and our data show that Mars also had water, a key component for a habitable environment during the earliest crustal history,” added Cavosi.
The scientific team has identified specific elements in this unique fragment of zircon through nanoscale imaging and spectroscopy,allowing the chemical composition of the objects to be determined. These include the elements iron, aluminum, yttrium and sodium.
“These elements were produced when zircon formed 4.45 billion years ago, suggesting that water was present during early Martian magmatic activity,” Cavosi explains.
Evidence of water streams and ancient lakebeds on Mars had already led scientists to suggest that about 4.1 billion years ago there was liquid water on the Red Planet, and in great abundance. This happened during the Noachian period on Mars, when the watery martian surface was intensively “bombarded” by asteroids.
The Red Planet is thought to have lost its water billions of years ago when the Martian atmosphere was destroyed by intense solar radiation. The loss of Mars’ atmosphere means that there is no longer anything to prevent water vapor from escaping into space.
According to the new study, though, liquid water may have existed on Mars even earlier than previously thought in the planet’s pre-Asian period.
“This new study takes us a step further in our understanding of early Mars by identifying telltale signs of water-rich fluids from when the grain formed, providing geochemical markers for water in the oldest known Martian crust,” the scientists explain..
2022 Curtin Research of the same zircon grain found that it had been “shocked” by a meteorite impact, making it the first and only known shocked zircon from Mars, Cavosi said.