Jack Prater on His Role in NASA's Perseverance

Many in the Poly community have played a role in NASA’s Mars rover Perseverance. Math Department Chair Jack Prater previously worked at NASA’s Jet Propulsion Laboratory (JPL) and learned that a part he designed during his tenure was used on the Perseverance. Read on for our interview with Jack about his time at JPL and his philosophy for teaching.

What did you design for the Perseverance? I built four of the antennas for the Curiosity mission. One used during the six-month cruise phase, two used for communication during Entry, Descent, and Landing (EDL)—the so-called seven minutes of terror—and one on the Curiosity rover itself. JPL is loath to introduce new designs because if you have a breakdown then the whole mission is lost. The antenna on Perseverance is one of the spare antennas I developed for Curiosity.  It was a two-year cycle to have the design developed, tested, fabricated, and deemed to be flight-worthy. It had to be able to survive on Mars for three years and cycle-tested for six months for the range of shocks and temperatures it would see. That was the last project I worked on before I came to Poly.

Tell us about your career before Poly? I graduated from undergrad and had left graduate school when a manager at JPL said, “Hey, come work here.” A year out of college I was working on  JPL's Deep Space Network (DSN). I spent the first eight years developing radios for the DSN's 70-meter ground-based antennas. These massive antennae are located around the globe and are specifically designed to communicate with spacecraft past the lunar orbit.

During that time I was also playing outdoor volleyball, eventually at a professional level, but I injured my shoulder. In the late 90s I started coaching at Caltech and then Poly and left JPL. I joined a startup in the Bay area developing electronic document retention software. The kind of technology you use in Snapchat to make your chats disappear. Then I started my family and went back to JPL.

My kids were at an age that I wanted more flexibility. I was talking to Steve Beerman and he said there’s an opportunity to be a math teacher. There were a couple of teachers in the Upper School that I went to college with then I ended up getting hired as a math teacher. I’ve been teaching and coaching volleyball here since then.

What was it like to watch the launch? If you go back and watch the video when they announce wheels down for the rover, the guy in the middle with two fists was one of my supervisors. He was the guy I delivered the antennas to and it was probably his decision to use the spare antennas from Curiosity on Perseverance. I was super excited for them. I still know a bunch of people in the control room and my old boss emailed me to say that those were my antennae.

How does teaching differ from engineering? As an engineer, I know when I deliver my work it is the best it can be. It’s going to meet all requirements and is going to fit. And the path you take to get there may take the path that isn’t most efficient, but in the end, you know the result is exactly what you want. You always know the parameters and what you’re dealing with. 

With teaching it’s more like surfing. Each wave is different and each kid is different. I never know if I’m right as a teacher but as an engineer you have documentation that you’re right. I’m teaching the same classes but each year it’s like a different wave. You’re never sure that what you’re doing is exactly right. You’re getting results that are meeting needs but could you have done it better? It’s ambiguous as to the end result and the impact you’re having on kids. Math is just the vehicle you’re using to impact them when what I really want is for them to be great problem solvers and successful individuals. Math is just a tool I use to help students learn other skills. You need 10-15 years to know your result. And I may never know.