Children are often mystified by remote control cars and how they can control them with a device while standing several feet away from them. This past week, Chris Tate was mystified by the same power-only he was controlling something 150 million miles away, on another planet.

The UT physics doctoral student had the rare opportunity to control one of the science instruments on NASA's Curiosity rover on Mars. Tate is working with Jeffrey Moersch, associate professor in the Department of Earth and Planetary Sciences, at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California.

The Curiosity rover has been on Mars for more than a week and is preparing to look for clues as to whether the planet ever was, or is still, an environment able to support microbial life. Daily, scientists give the rover instructions as to what data to collect during the Martian day, or sol, and then that data is downlinked to the scientists on Earth.

As a "payload uplink lead," Tate assembled and verified the instrument command sequence for his science team's instrument, a neutron detector. Overnight, his commands were sent to the rover, sitting millions of miles away on the Martian surface. They instructed the rover's neutron detector to power up, take data for a couple hours, save it all and send it back to Earth.

"It blows my mind to think that I told a robot on another planet 150 million miles away to do something and it happened," said Tate, of Woodbury, Tennessee.

Tate says the actions of the rover are meticulously planned from start to finish daily, and the duty of the payload uplink lead is to ensure that the rover accomplishes the science.

A neutron detector searches for hydrogen, found in water and hydrated minerals, thus leaving clues to whether an area was hospitable for life.

"This instrument can tell us a lot of information about the environment that we can't get from all those beautiful pictures coming down from the rover," said Tate. "And when integrated with the rest of the data, it's a powerful piece of the puzzle allowing us to characterize the environment so that we can learn about the current state of Mars and its long and varied history."

Tate arrived at JPL in August and will stay for ninety sols through November. He said this is a great learning experience, giving him insights into the inner workings of missions to the high level science, and he hopes it is not the last mission he works on.

"It is very humbling to work on something that is actually leaving the planet," he said. "It's a great testament to all the people who built and worked on this rover for so long."

Moersch said he's very proud of Tate.

"I've done this before on previous missions, and I can attest that it's a pretty mind-blowing experience, especially the first time you do it," he said. "It's astounding to think that something you did caused something to happen 150 million miles away on the surface of Mars."

The works of three UT professors are involved in the Curiosity mission-Moersch, Linda Kah, associate professor in earth and planetary sciences; and Ben Blalock, professor of electrical engineering and computer science.

The rocket carrying the rover launched from the Kennedy Space Center on November 26, 2011.