NASA rover set for landing attempt on Mars

·3-min read

NASA's Mars rover Perseverance is hurtling into the final stretch of its seven-month journey from Earth en route to a nail-biting landing attempt on an ancient lake bed where scientists hope to find signs of fossilised microbial life.

Perseverance, the most advanced astrobiology lab ever flown to another world, was headed for a self-guided touchdown inside a vast, rocky basin called Jezero Crater at the edge of a remnant river delta carved into the red planet billions of years ago.

Engineers at NASA's Jet Propulsion Laboratory near Los Angeles hope to receive confirmation of the landing, and possibly a first image from the rover, shortly after its arrival on Thursday (Friday AEDT).

Those transmissions will be relayed to Earth from one of several satellites already in orbit around Mars.

What makes Jezero Crater's terrain - deeply etched by long-vanished flows of liquid water - so tantalising to scientists also makes it especially treacherous as a landing site.

"It's full of the stuff that scientists want to see but stuff that I don't want to land on," Al Chen, head of JPL's descent and landing team, told reporters on Wednesday.

Getting Perseverance to its destination in one piece is far from assured, he added.

The multi-stage spacecraft must perfectly and swiftly execute a complex series of self-guided manouevres to slow its descent, avoid myriad surface hazards and plant itself gently upright on all six wheels.

The seemingly far-fetched sequence includes a perilous parachute deployment at supersonic speed and a rocket-powered "sky crane" designed to detach from the entry capsule, fly to a safe landing spot and lower the rover on tethers, before zipping off to crash a safe distance away.

The entire process is set to unfold in a heart-pounding interval NASA engineers half-jokingly refer to as the "seven minutes of terror."

NASA scientists describe Perseverance as the most ambitious of nearly 20 US missions to Mars dating back to a 1965 Mariner fly-by.

Larger and packed with more instruments than the four Mars rovers preceding it, the latest mobile robotic probe would build on previous discoveries that the fourth planet from the sun was once warmer, wetter and possibly hospitable to life.

The primary objective of Perseverance's two-year, $US2.7 billion endeavour is to search for signs of microbes that may have flourished on Mars some 3 billion years ago, about the time life was emerging on Earth.

Scientists hope to find biosignatures embedded in samples of ancient sediments that Perseverance is designed to extract from Martian rock for analysis back on Earth - the first such specimens ever collected by humankind from another planet.

Two future missions are planned to retrieve the samples and return them to NASA in the next decade.

Perseverance's payload also includes demonstration projects that could help pave the way for eventual human exploration of Mars, including a device to convert the carbon dioxide in Mars' atmosphere into pure oxygen.

Another experimental prototype carried by Perseverance is a miniature helicopter designed to test the first powered, controlled flight of an aircraft on another planet.

The United States is hardly alone in its fascination with Mars. Just last week, separate probes launched by the United Arab Emirates and China reached Mars orbit.