From his office in California, Keith Comeaux, flight director for the Curiosity rover Mars landing, used Skype to pay a two-hour virtual visit Aug. 23 to 32 fourth- and fifth-grade students in the gifted program at Copper Mill Elementary School in Zachary.
The students, who had been preparing for the session since the opening of school two weeks earlier, sat on a classroom floor and listened attentively as Comeaux described in detail the development and landing of the Mars vehicle.
For English language arts teacher Laura Compton, science and math teacher Molly Bryan and Tammy Wood, supervisor of special programs for the Zachary Community School District, the presentation was the culmination of a unit on space and Curiosity, which included programming robots on class computers and steering them around the path that Curiosity will take on Mars.
Comeaux’s presentation began with a video showing Curiosity’s perfect landing on Aug. 6. The video included snippets of viewers around the globe from Times Square in New York to the Denver Museum of Art to a group watching in Japan and their excitement when a voice from NASA calmly spoke the words, “Touchdown confirmed.”
“Mars is the most similar planet in the solar system to Earth,” Comeaux told the students. Mars is colder than Earth and has one-third the gravity of Earth. Because it is farther from the sun, it takes Mars two Earth years to go around the sun. As a result, Mars and Earth are closest to each other only once every two years.
“We have only a short window of time to launch,” Comeaux explained. “If we miss that window, we have to wait another two years to launch again.”
The rover landed exactly where the NASA scientists and engineers had planned, in the Gale Crater, very close to the planet’s equator. “There is a difference of six miles in elevation from the highest to the lowest part in the crater,” Comeaux said. “The diameter of Gale Crater is the same distance from Baton Rouge to New Orleans.”
And why did the scientists select Gale Crater for the landing? “It is a geologist’s paradise,” Comeaux said. “We think this used to be a big lake. It is likely that there was a river flowing into the lake. There is a layer of hard rock. We also see clays and sulfates. We think these might have preserved organic molecules. We believe these rocks were put down by water billions of years ago. It will be like reading a history book of Mars.”
Comeaux’s presentation included more than 50 images that showed the development of Curiosity from its beginning to a detailed explanation of the Mars landing.
One image showed a map of Mars with circles indicating the landing zones for past Mars missions with the earliest in the 1970s. “We have improved the capability to land in a small place,” Comeaux said. “We now have the ability to land in a very safe place near a very large mountain.” Inside the Gale Crater is Mount Sharp, more than 15,000 feet high.
The plan now is to lead Curiosity on a road trip from its landing site to Mount Sharp. “We have to get across some sand dunes. It could take a year to get there,” Comeaux said. “We are going to see many interesting things as we drive to Mount Sharp.”
On board Curiosity is a laboratory with 10 different instruments. A laser on top of the rover can “zap” rock samples to be examined in the lab. Seventeen different cameras can take photographs to send back to Earth.
The students were completely engaged as Comeaux described the different parts of Curiosity and the steps involved in the landing, but they could hardly wait to ask him their questions.
“What motivated you to keep trying to get on at NASA?” John Borg asked Comeaux.
“When I first finished school, I started working at NASA, but after that, NASA was not hiring, so I went to work for a commercial satellite company,” Comeaux said. “But when this mission opened up, they gave me a call and invited me to come work.”
Olivia Loftin wondered what Comeaux enjoyed most about his job. “When we were building and testing Curiosity, it was just a box on a table, a computer,” he said. “In two years, we put it together.”
He explained how satisfying it was to work with a team, how everyone contributes in his or her own way to create the finished product. “Nobody at NASA could do this by yourself,” he said.
Presley Stagg wondered what it felt like when Curiosity landed. “That guy jumping up and down in the video, that was me,” Comeaux said. “We worked so hard on it, so long, and everything went so perfectly. We were just overjoyed.”
Briann Bankston asked if there would be more rovers on Mars. “I don’t know what rover will be next,” Comeaux said. “We would like to have one that would land on Mars and then fly back to Earth.”
Mikey Varnado wondered about the hardest part of directing the landing. Working together with so many people can be challenging, Comeaux said. “If you are looking to be scientists and engineers, you have to understand that scientists and engineers have to work in large teams,” he said.
Dylan Jackson asked Comeaux who or what inspired him to be a NASA scientist. “I have always had an interest in mathematics and science,” Comeaux said, “but I was more interested in airplanes. I liked airplanes more than rockets, but I always wanted to go into space.”
One of the most revealing questions came from Jeffrey Brent, who asked Comeaux what scared him the most about the project. “In the beginning there were a lot of technical difficulties and difficulties meeting our schedule,” Comeaux said. “But recently, the entry, descent and landing you can’t test because the atmosphere on Mars is so different, and the gravity is so different. This was never tested, so we really had seven minutes of terror to see if it would work.”
School principal Dewey Davis asked Comeaux if in hindsight there was anything that they would have done differently. “There was one glitch,” Comeaux said. “We have a weather station on Curiosity. It has wind sensors that are very delicate. We think in landing, a couple of rocks may have damaged these.”
The students, all between 8 and 10, listened intently to the two-hour presentation, which Wood called “a once in a lifetime experience.”
“Follow your dreams,” Comeaux told the kids. “You may not know what you want to do, but your curiosity will lead you where you will be most happy.”