Technology
Nasa’s Perseverance Mars rover to endure ‘7 minutes of terror’ before landing this week
NASA’S Mars rover Perseverance hits the final stretch of its seven-month journey from Earth this week, beginning what engineers at the US space agency are calling its “seven minutes of terror”.
The six-wheeled rover is set to emit a radio alert as it streaks into the thin Martian atmosphere, and by the time that signal reaches mission managers some 127million miles (204million km) away, Perseverance will already have landed on the Red Planet – hopefully in one piece.
Perseverance is expected to take seven minutes to descend from the top of the Martian atmosphere to the planet’s surface.
That’s less time than the 11-minute-plus radio transmission to Earth.
Thus, Thursday’s final, self-guided descent of the rover spacecraft is set to occur during a white-knuckled interval that JPL engineers affectionately refer to as the “seven minutes of terror.”
Al Chen, head of the JPL descent and landing team, called it the most critical and most dangerous part of the £1.6billion ($2.7billion) mission.
Nasa’s Perseverance rover is the size of a small car[/caption]
“Success is never assured,” Chen told a recent news briefing.
“And that’s especially true when we’re trying to land the biggest, heaviest and most complicated rover we’ve ever built to the most dangerous site we’ve ever attempted to land at.”
Much is riding on the outcome.
Building on discoveries of nearly 20 U.S. outings to Mars dating back to Mariner 4’s 1965 flyby, Perseverance may set the stage for scientists to conclusively show whether life has existed beyond Earth, while paving the way for eventual human missions to the fourth planet from the sun.
A safe landing, as always, comes first.
Perseverance will land on Mars’s Jezero crater in 2021[/caption]
Success will hinge on a complex sequence of events unfolding without a hitch – from inflation of a giant, supersonic parachute to deployment of a jet-powered “sky crane” that will descend to a safe landing spot and hover above the surface while lowering the rover to the ground on a tether.
“Perseverance has to do this all on her own,” Chen said. “We can’t help it during this period.”
If all goes as planned, Nasa’s team would receive a follow-up radio signal shortly before 4pm ET (9pm GMT) confirming that Perseverance landed on Martian soil at the edge of an ancient, long-vanished river delta and lake bed.
From there, the nuclear battery-powered rover, roughly the size of a small SUV, will embark on the primary objective of its two-year mission.
The rover will search for signs of past and present life in the crater[/caption]
It will engage a complex suite of instruments in the search for signs of microbial life that may have flourished on Mars billions of years ago.
Advanced power tools will drill samples from Martian rock and seal them into cigar-sized tubes for eventual return to Earth for further analysis.
Provided all goes to plan, they will be the first such specimens ever collected by humankind from the surface of another planet.
Two future missions to retrieve those samples and fly them back to Earth are in the planning stages by Nasa, in collaboration with the European Space Agency.
Perseverance has 43 titanium-coated tubes housed in its belly where it will deposit samples of Martian rock and soil[/caption]
Perseverance, the fifth and by far most sophisticated rover vehicle Nasa has sent to Mars since Sojourner in 1997, also incorporates several pioneering features not directly related to astrobiology.
Among them is a small drone helicopter, nicknamed Ingenuity, that will test surface-to-surface powered flight on another world for the first time.
If successful, the four-pound (1.8-kg) whirlybird could pave the way for low-altitude aerial surveillance of Mars during later missions.
Another experiment is a device to extract pure oxygen from carbon dioxide in the Martian atmosphere.
The tool could prove invaluable for future human life support on Mars and for producing rocket propellant to fly astronauts home.
The mission’s first hurdle after a 293-million-mile (472-million-km) flight from Earth is delivering the rover intact to the floor of Jerezo Crater.
Scientists believe the 28-mile-wide (45-km-wide) expanse may harbour a rich trove of fossilized microorganisms.
“It is a spectacular landing site,” project scientist Ken Farley told reporters on a teleconference.
What makes the crater’s rugged terrain – deeply carved by long-vanished flows of liquid water – so tantalizing as a research site also makes it treacherous as a landing zone.
The descent sequence, an upgrade from Nasa’s last rover mission in 2012, begins as Perseverance, encased in a protective shell, pierces the Martian atmosphere at 12,000mph (19,300kph), nearly 16 times the speed of sound.
After a parachute deployment to slow its plunge, the descent capsule’s heat shield is set to fall away to release a jet-propelled “sky crane” hovercraft with the rover attached to its belly.
Once the parachute is jettisoned, the sky crane’s jet thrusters are set to immediately fire.
They will slow the craft’s descent to walking speed as it nears the crater floor and self-navigates to a smooth landing site, steering clear of boulders, cliffs and sand dunes.
Hovering over the surface, the sky crane is due to lower Perseverance on nylon tethers, sever the chords when the rover’s wheels reach the surface, then fly off to crash a safe distance away.
Should everything work, deputy project manager Matthew Wallace said, post-landing exuberance would be on full display at JPL despite COVID-19 safety protocols that have kept close contacts within mission control to a minimum.
“I don’t think COVID is going to be able to stop us from jumping up and down and fist-bumping,” Wallace said.
Mars facts
Here’s what you need to know about the Red Planet…
- Mars is the fourth planet from the Sun
- It is named after the Roman god of war
- The landmass of Mars is very similar to Earth but due to the difference in gravity you could jump three times higher there than you can here
- Mars is mountainous and hosts the tallest mountain known in the Solar System called Olympus Mons, which is three times higher than Everest
- Mars is considered to be the second most habitable planet after Earth
- It takes the planet 687 Earth days to orbit the Sun
- So far, there has been 39 missions to Mars but only 16 of these have been successful
Most read in Science
In other news, China’s Tianwen probe captured rare footage of the rocky surface of Mar after entering the planet’s orbit last week.
Elon Musk has warned that humanity may “self-extinguish” before we can colonise Mars.
And, dead alien civilisations could be littered all over our galaxy, according to a new study.
What do you make of Nasa’s Mars mission? Let us know in the comments!
We pay for your stories! Do you have a story for The Sun Online Tech & Science team? Email us at tech@the-sun.co.uk
