SIR – I’m not sure how us Earthlings will benefit if NASA’s current robotic exploration of Mars does discover that life once existed on a planet that is very cold and dry, with a thin 95 percent carbon dioxide atmosphere and subject to violent annual dust storms and widespread volcanism.

If scientists are looking for a new place to set up home before the sun completes its life-cycle, they can forget the Red Planet.

Mind you, if the unmanned device falls down one of its vast canyons that stretch for thousands of miles reaching depths of four miles, they will have wasted billions of dollars, an amount President Obama could have found a better use for considering his country is trillions of dollars in debt.

D Rhodes, Croscombe Walk, Bradford