Great Escape: Mason Physicist Expands Satellite’s Atmospheric Studies

Erdal Yigit composite with illustration by Evan Cantwell. Computer generated image background Credit: NASA/JPL-Caltech

Erdal Yigit composite with illustration by Evan Cantwell. Computer generated image background Credit: NASA/JPL-Caltech

The Mars Atmosphere and Volatile EvolutioN (MAVEN) satellite was created and launched in 2013 by a large team of scientists from around the world. When NASA decided last year to extend MAVEN’s core team to include theoreticians and modelers, it reached out to a number of renowned researchers, including physicist Erdal Yiğit.

Using six focus questions to create several teams throughout the globe, NASA invited researchers to choose a single science question to address. Yiğit, who teaches in George Mason University’s School of Physics, Astronomy, and Computational Sciences as a junior tenure-track faculty member, was at the University of California, Berkeley at the time of the request. He was working on Mars research with his colleague, research physicist Scott England, at the Space Sciences Laboratory.

The pair proposed to study the focus topic “How do lower atmospheric waves influence the upper atmosphere on Mars?” This subject is one of the key steps toward better understanding atmospheric escape on Mars, one of MAVEN’s prime goals. When Yiğit transferred to George Mason last year, he brought his component of the MAVEN research with him.

Atmospheric escape, or the loss of planetary atmospheric gases to outer space, is a natural occurrence with all planets. “The question is how much escape occurs,” Yiğit explains. “This is a fundamental question, because whether there’s life, or can be life on that planet, the atmosphere plays an important role. Understanding how a planet loses its air, so to speak, is essential.”

Earth experiences relatively little atmospheric escape, so it has a thick, protective atmosphere and a natural magnetic field environment surrounding it. Mars, lacking a strong intrinsic magnetic field and with an atmosphere 100 times thinner than Earth’s, has little protection from the sun’s energetic particles. It experiences volatile extremes such as tremendously low temperatures, high-pressure solar winds and poisonous gases.

Yiğit is working to interpret and scrutinize the data MAVEN is collecting now that it has entered the atmosphere of the Red Planet and begun to send back information.

“Our role is to work on the science part when the data actually become finalized and can be really used,” he says. “We will do computational simulations to explain why the data are the way they are. I don’t know what we will see.”

Yiğit is planning to continue working with his research partner at UC Berkeley this summer, and hopes to engage an undergraduate student from Mason to work with the data or learn the model. This phase of the project should be completed within the next six months, and Yiğit plans to continue his work for two years after that.

For now, though, he and England are busy setting up the theoretical and modeling framework that will help make predictions and interpret the data, discussing their work with the other team members through weekly teleconferences and a constant stream of emails.

“It’s pretty much a hot time right now,” Yiğit says. “We already have a good idea of what the roles of these atmospheric waves are on Earth and we are on a good track to quantify such effects on Mars, as well. We’ve been able to determine quantitatively how the waves influence the way the atmosphere circulates. It’s a very promising mission.”