‘Seven minutes of terror’: Nasa Perseverance rover’s landing on Mars explained
The Perseverance rover, built at Nasa’s Jet Propulsion Laboratory (JPL) in Southern California, lifted off from Kennedy Space Center on July 30, 2020.
After travelling for nearly seven months, Nasa’s Perseverance rover is in the final few days of its space travel before it attempts landing in the most challenging site ever targeted on Mars. The entry, descent, and landing phase of the Mars mission are scheduled for February 18, a phase often referred to by engineers as “seven minutes of terror”. The science exploration program of the National Aeronautics and Space Administration shared a video on Friday explaining the challenges of the mission.
“Entry, descent and landing often referred to as seven minutes of terror. Because it takes about seven minutes to get from the top of the atmosphere of Mars to the ground safely,” Swati Mohan, Mars 2020 guidance, navigation and control operations lead, said.
Around 10 minutes before the atmospheric entry on February 18, Nasa’s Perseverance rover will get rid of the spacecraft, and enter into the Martian atmosphere at 12,000-13,000 miles per hour. The heat shield will dissipate the initial energy generated through friction in the atmosphere and the vehicle will continue flying through it by transforming into an aircraft actively guiding itself.
Once the Perseverance rover is slow enough, Nasa scientists will deploy a supersonic parachute, the biggest they have sent to another planet, critical for further slowing down the vehicle. It will then look for a relatively safe landing in Jezero Crater by detaching the heat shield so that the rover can actually see the ground using terrain relative navigation. While descending on the parachute, the technology will be used to capture the images of the Martian surface and based on that, the rover will decide on the landing site.
“This is finally like landing with your eyes open. Having this new technology really allows Perseverance to land in much more challenging terrain than Curiosity or any previous Mars mission could,” Mohan said.
After Perseverance figures out its position, the engineers will jettison the backshell and the supersonic parachute and light up the rockets. The rockets will help steer the rover to a nearby safe landing spot. When the descent stage is about 20 metres away from the ground, the skycrane manoeuvre will be activated to let the rover hit the ground. After the rover lands on the surface, the descent stage will cut loose from the rover and fly away to a safe distance.
The Perseverance rover, built at Nasa’s Jet Propulsion Laboratory (JPL) in Southern California, lifted off from Kennedy Space Center on July 30, 2020, taking advantage of a once-in-every-two-years launch window. China’s Tianwen-1 mission and the UAE’s Hope probe were also launched during the same window in order to minimise the required energy to get from Earth to Mars.