Nasa completes six years of Curiosity on red planet

Washington DC: NASA's Curiosity rover — a mission that has spotted evidence of liquid water as well as potential signs life and habitability on Mars - has completed six years on the red planet.

"I touched down on #Mars six years ago. Celebrating my 6th landing anniversary with the traditional gift of iron oxide. (It puts the red in Red Planet.)," the rover's social media handle tweeted.

The Mars Science Laboratory mission's Curiosity rover landed on the red planet's Gale Crater on August 6 using a series of complicated landing manoeuvres never before attempted. Curiosity's mission is to determine whether the red planet ever was, or is, habitable to microbial life.

The rover, which is about the size of a car, is equipped with 17 cameras and a robotic arm containing a suite of specialised laboratory-like tools and instruments. The specialised landing sequence, which employed a giant parachute, a jet-controlled descent vehicle and a bungee-like apparatus called a "sky crane," was devised because tested landing techniques used during previous rover missions could not safely accommodate the much larger and heavier rover. The Curiosity rover is currently experiencing a global storm that has been raging in Mars for weeks.

In 2013, the Curiosity rover found that ancient Mars had the right chemistry to support living microbes.

The rover discovered evidence of sulphur, nitrogen, oxygen, phosphorus and carbon - key ingredients necessary for life - in the powder sample drilled from the "Sheepbed" mudstone in Yellowknife Bay.

The sample collected by the rover also revealed clay minerals and not too much salt, which suggests fresh, possibly drinkable water once

flowed there.