Mars may have hosted life for millions of years longer than previously thought

London, United Kingdom

Water on Mars: Mars may have hosted life for much longer than once believed, according to scientists. How much longer? Its habitable period might actually have been longer by millions of years.

Water on Mars

In its ancient past, Mars boasted oceans, lakes, and rivers, painting a picture reminiscent of early Earth during the solar system's infancy.

As per estimates, the gradually changing climate rendered the red planet barren, as we know it today.

Also read | ‘Martians wanted’: NASA is looking for volunteers to live in a Mars simulator for a year

Competing theories exist regarding the disappearance of Martian water. Some propose it evaporated into space as the planet's atmosphere thinned, while others suggest it became trapped within the planet's crust, forming an icy permafrost layer.

Traditionally, scientists thought Mars lost its water during the Hesperian period, about 3.7 to 2.9 billion years ago. However, recent findings propose water may have persisted until the late Hesperian period.

However, a research team by the UK's Imperial College has now found signs that water was abundant in a 154 km-diameter basin just south of Mars' equator called Gale Crater. According to them, Mars had water "long after the planet was thought to have become dry and inhospitable."

Why does water on Mars matter?

The findings, as per the researchers, "have implications for our understanding of Mars' changing climate, as well as where we now look for signs of habitability." 

Using data from the Curiosity rover's exploration, researchers spotted deformed layers in Mars' desert sandstone, which they say "could only have been formed by water". 

Also read | Life on Mars? Curiosity rover discovers that it was once a 'planet of rivers'

Dr Steven Banham, the lead author of the study published in Geology, noted that "the sandstone revealed that water was probably abundant more recently, and for longer than previously thought—but by which process did the water leave these clues? "

"This water might have been pressurised liquid, forced into and deforming the sediment; frozen, with the repeat freezing and thawing process causing the deformation; or briny, and subject to large temperature swings."

"What's clear is that behind each of these potential ways to deform this sandstone, water is the common link," he noted. 

(With inputs from agencies)