The landing of NASA’s Perseverance Rover: An engineering student’s perspective

Joel Majano

Cannon Writer

Mars: a world so far and foreign, but when you look at it closer, you can imagine how the Earth looked before it got to its current state, with no civilization anywhere to be found. When I first saw the images coming back from NASA’s Perseverance rover, I was honestly just taken aback, and began thinking how incredible it is for us to be able to see a completely different world in real time (well, delayed by 11 minutes, thank the speed of light for that).

Let’s go back a few days before that moment, shall we?

February 18th, 2021 was a monumental day for anyone even remotely interested in space, and an even bigger day for the folks over at NASA’s Jet Propulsion Laboratory (JPL) who had launched the Perseverance rover to Mars back in July 2020. NASA had a perfect record in landing vehicles on Mars going into Perseverance’s landing, so while there was still a degree of risk, the chances of Perseverance landing were not bad. NASA’s first rover, Sojourner, landed on Mars in July 1997 and it surpassed its planned mission length by over 70 sols (the Mars equivalent of a day). Furthermore, NASA had landed the twin rovers Spirit and Opportunity back in January 2004, using inflatable airbags to help the rover come to rest safely on the Martian surface. Finally, Curiosity landed on Mars in August 2012 using a novel “sky crane maneuver” to land gently.

Small detour for my quick thoughts

As an engineer, seeing the sky crane system work successfully was just jaw dropping and breathtaking because there are so many different systems that must work correctly to allow for a successful maneuver. First of all, the “jetpack” that is the sky crane system must slow itself down enough, then hover over the ground, slowly lower the rover, cut away from the rover, and fly a safe distance away from the rover… autonomously. Perseverance added a whole new layer of difficulty to this maneuver by using computer vision to actually choose the landing location. The use of “Terrain Relative Navigation” is the first time that something like this would be used to land on Mars, so the JPL team was anxious to see how it would perform. The complexity of this system starts with acquiring a radar lock on the ground, then picking  a mostly flat spot of land for landing. Next, the jetpack (which is part of the sky crane system) diverts to this location while still descending towards the Martian surface. Finally, the system picks a final landing location, and uses the sky crane maneuver to gently place the rover on the ground.

Okay back to Perseverance

NASA and the JPL team streamed the day’s activities from the control room that would be receiving back updates from the rover as it proceeded autonomously through the different phases of Entry, Descent, and Landing (EDL). That was all that JPL could do back here on Earth, as there would be no way to control the rover from earth due to the 11 minute delay it takes for any type of transmission to reach Mars. Minutes before the confirmation of landing, as the team was getting updates from the rover, letting them know that it was safe and proceeding as planned through its stages, the tension in the room was palpable. I was sitting in front of my computer, watching alongside the JPL team, both of us having the same amount of control over what would occur before our very eyes.

Parachute Deploy… Landing vision system has produced a valid solution…Sky crane maneuver has started…

TOUCHDOWN CONFIRMED!

There are no words I can use to describe the feeling when I heard that callout. This was the first time that I watched something like this live, and it was overwhelming to say the least. Big events like this, such as the Falcon Heavy landing of the two side boosters were already breathtaking and fascinating, but this was just on another level. The greatness that humanity can achieve when the brightest minds work together towards a common goal is nothing short of amazing. The first image shot by Perseverance was sent relatively soon after landing, and while it was low resolution, the audience knew that the landing had gone off without a hitch, and the rover was safe on Mars. I could not begin to imagine the relief and joy that the JPL team felt at that very moment, as they had just landed another rover on Mars, keeping their absolutely spotless record of landing vehicles on the red planet.

Fast forward a few days.

Due to the great distances involved, the data rate between Earth and Mars are not the greatest, as one could expect, thus the high resolution images and videos taken by the new camera systems on Perseverance take many hours/days to reach Earth. As more images came back, NASA periodically posted them on their social channels, allowing all of us back on Earth to see what Perseverance was looking at in its new home. The quality of the images is stunning and we can clearly see the Martian landscape filled with many rocks and mountains. My favourite moment was when NASA was finally able to share videos and sound recordings taken by Perseverance. The JPL team had hoped to record the sound of the landing, but unfortunately the onboard computer (which runs Linux!) was unable to record the data it was receiving from the microphone.

In a press conference held a few days after the safe touchdown of Perseverance, the landing video was shown to the press and everyone watching the live stream. The video begins right before parachute deployment and continues all the way down until the sky crane cuts away from the rover and flies a safe distance away from Perseverance. Next, two audio clips recorded by Perseverance were played live, and the audience could clearly hear the sounds made by the onboard devices, but we could also hear the Martian wind, which I did not expect to be able to hear any time soon with my own ears.

Okay, it’s been a long read, but if you have stuck around this far, I thank you. This was an incredible experience, and I will always remember Perseverance’s landing and all the emotions I went through while watching this event. The engineering work by the entire JPL team was fantastic to watch, and seeing it perform as well as it did was inspiring. I really look forward to Perseverance’s next steps on Mars, which includes releasing a helicopter named Ingenuity, and testing rocks for past microbial life. As a final note, I encourage everyone even slightly interested in this to go watch the landing footage because, at the very least, it truly is out of this world.