Sur­face of Mars shows scars of glaciers like Canada’s Arc­tic

Red planet may have sus­tained life, ex­pert says

National Post (National Edition) - - NEWS - HINA ALAM

VAN­COU­VER • The deep val­leys scarred into the sur­face of Mars un­der thick sheets of ice show that the planet once mir­rored the Cana­dian High Arc­tic, says a new study.

Pub­lished Mon­day in the jour­nal Nature Geo­science, the study says many of the val­ley net­works carved into the sur­face of Mars were formed by wa­ter melt­ing be­neath glacial ice. It means there were fewer free-flow­ing rivers than pre­vi­ously thought.

Study au­thor Anna Grau Galofre, a for­mer Univer­sity of Bri­tish Columbia PhD stu­dent in the de­part­ment of Earth, ocean and at­mo­spheric sciences, said about 3.5-bil­lion years ago the Mar­tian sur­face looked like the sur­face of Canada 20,000 years ago.

“We’re talk­ing about a planet that’s painted like a brother of Earth,” she said.

Grau Galofre and her team com­pared sur­face data of Mars with that of Devon Is­land in the Cana­dian Arc­tic. The study de­scribes Devon Is­land as a cold, dry, po­lar desert, where the glaciers and their re­treat im­i­tate what took place on Mars bil­lions of years ago.

“Imag­ine ice sheets that are kilo­me­tres thick, re­ally, re­ally thick,” she said.

“If you were to just lift the ice sheet and see be­low, you would see a land­scape. And this land­scape is con­sti­tuted of sev­eral dif­fer­ent chan­nels, ex­panded path­ways like the plumb­ing of the ice.”

What this tells sci­en­tists is that while there may have been a warm and wet Mars on which there was rain­fall, it’s far more likely that the planet’s sur­face re­sem­bled that of the Cana­dian Arc­tic, she said.

“It is like a time evo­lu­tion of the cli­mate that we’re look­ing at here. There were the warm and wet pe­ri­ods that talked about the oceans. And there were the cold and icy pe­ri­ods.”

This could mean that the cli­mate on Mars ei­ther changed slowly through time from a cooler to a warmer pe­riod, or the other way around, she said.

The new find­ings bring up an “in­ter­est­ing dis­cus­sion point” about life on Mars, Grau Galofre said.

“That’s ac­tu­ally not a bad thing in terms of an en­vi­ron­ment to sus­tain life.”

Lake Vos­tok on Antarc­tica is cov­ered by a thick sheet of ice but has plenty of life, such as bac­te­ria, she said.

“And they have been there for a long time, up to a mil­lion years, pretty much iso­lated by the ice sheet.”

The ice guar­an­tees the crea­tures get wa­ter and also pro­vides a sta­ble en­vi­ron­ment, es­pe­cially on a planet like Mars, which can have sear­ing days and freez­ing nights, said Grau Galofre.

The ice sheet also pro­tects life from so­lar ra­di­a­tion, she added.

The study could be ex­panded to in­clude the Jezero Crater, where NASA’s Per­se­ver­ance is sched­uled to land on Mars, be­cause it may have once har­boured life, she said.

Mars is the first and ob­vi­ous place to start look­ing for life be­cause it still has north­ern and southern ice caps, as well as a small frac­tion of wa­ter in the atmosphere, Grau Galofre said. Ev­i­dence of wa­ter shows there is life or there was a time when life ex­isted, she said.

“That’s a big step in terms of try­ing to an­swer this ques­tion — where are we com­ing from and are we alone in the uni­verse,” Grau Galofre said.

“I think by finding life some­where else in the uni­verse we can also an­swer a lot about what is life and what are we do­ing here.”

WHERE ARE WE COM­ING FROM, AND ARE WE ALONE IN THE

UNI­VERSE?

HAND­OUT-ANNA GRAU GALOFRE / THE CANA­DIAN PRESS

UBC re­searchers have con­cluded that the early Mar­tian land­scape prob­a­bly looked sim­i­lar to this im­age of the Devon ice cap in the Cana­dian Arc­tic. Re­ced­ing glaciers likely left the red planet scarred with deep crevasses, they say.

Newspapers in English

Newspapers from Canada

© PressReader. All rights reserved.