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Page 1: NASA picks ancient Martian river delta for rover landing

NASA has picked an ancientriver delta as the landing sitefor its Mars 2020 rover, tohunt for evidence of past lifeon the earth’s neighbouringplanet, offi��cials said onMonday.

Even though the Red Pla-net is now cold and dry, thelanding site, Jezero Crater,was fi��lled with a 500-meterdeep lake that opened to anetwork of rivers some 3.5 to3.9 billion years ago.

“The delta is a good placefor evidence of life to be de-posited and then preservedfor the billions of years thathave elapsed since this lakewas present,” Ken Farley,Mars 2020 project scientistat NASA’s Jet Propulsion Lab-oratory, told reporters on aconference call.

Experts believe the 45-kmwide basin could have col-lected and preserved an-cient organic molecules andother signs of microbial life.

At least fi��ve diff��erent kinds

of rocks, including “claysand carbonates that havehigh potential to preservesignatures of past life,” arebelieved to lie in the crater,just north of the Martian eq-uator, NASA said in astatement.

Carbonate rock is pro-duced by the interaction ofwater, atmospheric gases

and rock, and leaves cluesabout habitable environ-ments, said Farley.

Scientists have debatedwhere to land the rover forthe past four years, and whit-tled down their decisionfrom more than 60 possiblesites.

The $2.5 billion rover isplanned to launch in July

2020, and land in February2021.

Mars 2020 is designed toland inside the crater andcollect samples that willeventually be returned toEarth for further analysis,perhaps by the later 2020s.

Perilous landingBut fi��rst, the rover has tomake it to the surface intactand upright, dodging a fi��eldof boulders, sand traps andthe edges of the delta.

Mars 2020 will use thesame sky crane landing thatsuccessfully delivered NA-SA’s unmanned Curiosityrover to a location calledGale Crater on Mars back in2012.

Gale Crater, with its manylayers of sediment, was cho-sen to tell the story of howMars transitioned from awarm, wet planet to the fri-gid and dusty one it is today.

Mars 2020 is designed tolook at rocks on a fi��ner scale,seeing what biosignaturesare preserved.

NASA picks ancient Martianriver delta for rover landingThe basin may have preserved organic molecules and signs of microbial lifeAgence France-PresseTampa

Landing spot: Water carved channels and transportedsediments to form fans and deltas within lake basins. * AFP