The Spacecraft Tarot: Perseverance
Strength helps you overcome all obstacles.
Whether you are battling an adversity, a competitor, or an inner demon, the urge to give up will be strong. You will be tempted to admit defeat, perhaps because you are exhausted, or maybe because you tend to second-guess yourself. You must tap into your inner strength to conquer surpass the roadblocks on your path.
Although current Martian conditions are too dry and too cold to support life today, the environment may have been better-suited three and half billion years ago. Back then, when the climate used to be much warmer, Jezero Crater was home to a lake about the size of Lake Tahoe. The question NASA scientists have — and the question the Perseverance Mars Rover is on a mission to answer — could this lake have been teeming with living microbes?
On July 30, 2020, United Launch Alliance Atlas V rocket launched from Cape Canaveral Air Force Base, Florida, propelling the Mars 2020 spacecraft, with the Perseverance rover and the Ingenuity Mars Helicopter inside, on a path to the Red Planet. This specific launch window, and the unique positions of the planets in their orbits at the time, afforded the spacecraft an opportunity to reach Mars in a matter of months rather than years.
After cruising for 203 days and covering 293 million miles, the spacecraft entered the approach subphase of the mission and prepared for its final descent to the Martian surface. In the final 45 days leading up to landing, teams made navigation measurements and had the opportunity to make last adjustments to the spacecraft’s trajectory — however, these were ultimately not needed because of the remarkable accuracy of the spacecraft’s path.
Landing a rover on Mars is always difficult. Perseverance was no exception. The price of landing in Jezero Crater, where life could have possibly existed long ago, is the risk of landing on hills, rocks, or dunes. In addition, the vast distance between Mars and Earth delays the signals that we send to the spacecraft by about ten minutes. In the seven minutes the spacecraft takes to travel from the top of the Martian atmosphere to the ground, teams have almost no communication with the vehicle. These seven minutes are referred to as “the seven minutes of terror.”
Only about half of the attempts from all of the world’s space agencies to Mars actually make it — and Perseverance had the added challenge of landing in the most difficult terrain yet.
To successfully land Perseverance on Mars required exactly the trait that inspired the rover’s name (a name provided by Alexander Mather, who was in seventh grade at the time). Teams at NASA’s Jet Propulsion Laboratory (JPL) faced the challenge of completing the most complicated landing on Mars yet with the added difficulty of working in quarantine during the COVID-19 pandemic.
On February 18, 2021, Entry, Decent, and Landing lead Al Chen addressed his team before beginning the landing attempt: “It hasn’t been easy. I don’t think we’ve even all been at the same room at the same time.”
After shedding the cruise stage that ferried Perseverance and Ingenuity to Mars, the spacecraft used a technique called “guided entry” to compensate for drag and variations in the density of the Martian atmosphere while small thrusters adjusted the angle and direction of lift. As the spacecraft entered the Martian atmosphere, the temperature of the heat shield reached temperatures of about 2,370 degrees Fahrenheit.
After the rover’s parachute deployed, the heat shield separated and revealed cameras that assisted Terrain-Relative Navigation technology. This technology autonomously surveyed the landscape and decided on the best place to land. Once the descent stage sensed that the Martian surface was only 65 feet away, the spacecraft initiated the sky crane maneuver, lowering the rover gently down to the surface on nylon cords. Blades severed the cords and the descent stage flew far enough away to pose no risk to the rover before crashing into the planet.
The Perseverance landing team felt a wave of relief and joy as the rover returned high-resolution imagery of the Red Planet. After years of blood, sweat, and tears, and seven final minutes of nail-biting terror, Perseverance had finally arrived home.
Soon after the spacecraft completed the most complicated Martian landing ever attempted, teams had even more to celebrate when the Ingenuity Mars Helicopter (also named by a student — Vaneeza Rupani, who was a high schooler at the time) completed the first powered flight on another planet.
Teams designed Ingenuity to accommodate for an atmosphere with only 1% of Earth’s density, as well as temperatures that can drop below minus 130 degrees Fahrenheit. For this reason, the helicopter is extremely light, with rotor blades that spin extremely fast by Earthly standards.
On April 19, 2021, Ingenuity took to the skies for the first time. Since then, the helicopter has completed a total of 33 flights adding up to almost an hour of flight time. Ingenuity proved that powered flight will be an effective method for scouting and transporting materials across the Martian landscape — so well, in fact, that NASA and ESA have decided to incorporate two Ingenuity class helicopters into the Mars Sample Return campaign, currently planned to land on Mars within the decade.
The campaign will retrieve samples of Martian rocks and soil that Perseverance collects and caches. The rover has one arm that drills into the rock, and another arm to collect the samples into tubes.
On January 29, 2023, Perseverance deposited its tenth and final tube of its first sample depot on the Martian surface. These tubes include igneous and sedimentary rock cores that scientists hope will provide a peek into the geologic processes that formed Jezero Crater billions of years ago. The rover also deposited an atmospheric sample and a “witness tube” that is used to check for any chemical contamination from Earth.
Perseverance deposited the titanium tubes in a zigzag pattern, with each sample about 15–50 feet away from one another.
As of now, Earth is the only planet we know of that hosts life. If Perseverance finds evidence of ancient life on Mars, this would suggest that life is a lot more common in our universe than we previously thought.
Perseverance also carries a number of demonstrations that will help prepare us to send future human explorers to the Red Planet. One of these experiments is the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE), a toaster-sized device that uses solid oxide electrolysis convert carbon dioxide in the Martian atmosphere into oxygen. The Martian atmosphere is about 96% carbon dioxide and only 0.13% oxygen — compared to 0.04% and 21% on Earth, respectively.
MOXIE has been breaking records with this method that may one day, not only make the atmosphere breathable for explorers, but also provide an oxidizer for return missions to Earth.
Perseverance is a reminder of the strength we need to thrive under pressure. Despite innumerable obstacles, Perseverance is safely on Mars, checking off scientific objectives that will improve our understanding of astrobiology and prepare us for future human missions to the Red Planet.
