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A CU-led mission seeks to understand the planet’s climate and if Mars could have been habitable.

On Oct. 30, 1938, millions of radio listeners in the United States were stunned to hear that Earth was under attack by Martians. Panicked listeners packed their cars and fled the cities. Many were reportedly treated for shock and hysteria. What they were hearing was a radio play of H.G. Wells’ science fiction novel The War of the Worlds.

Seventy-five years later, a University of Colorado Boulder-led mission will launch in November to learn more about the Red Planet, which has captured the public’s imagination and intrigued scientists for years.

The Mars Atmosphere and Volatile Evolution (MAVEN) is the first mission devoted to studying the ionosphere, or upper atmosphere, of Mars in unprecedented detail. It will explore and seek to understand how the loss of atmospheric gas has changed the climate of Mars.

“There’s so much we don’t understand about Mars,” says professor Bruce Jakosky, MAVEN’s principal investigator based at CU-Boulder’s Laboratory for Atmospheric and Space Physics. “We barely know what questions to ask. We’re sending up scientific instruments that will answer the questions we’re asking, but we also hope to get answers for questions we didn’t even think to ask.”

Jakosky has devoted more than a decade of his scientific career on this mission, starting with his initial conversation 10 years ago with a handful of scientists to propose it to NASA.

Previous missions to Mars show geological features and chemical evidence that there was once liquid water on Mars.

The spacecraft will orbit Mars for one year collecting data on the sunlight and solar winds that hit the upper atmosphere and the resulting processes causing the Martian ionosphere to be lost to space. Scientists think the loss could explain the climate change on Mars that has occurred over the last four billion years. The result is a planet without enough atmospheric pressure to maintain liquid water and carbon dioxide, the building blocks of life.

Jakosky is optimistic they’ll receive enough measurements during the year MAVEN is expected to be in orbit. Because energy input from the sun varies on an 11-year time scale, the hope is that MAVEN will last for an extra decade — an entire solar cycle — to get a clearer picture of the processes that occur in the ionosphere.

“The real question most people are interested in is, ‘Is there life on Mars today or in the past?’ ” Jakosky says. “MAVEN isn’t going to answer that, but it will help us understand the constraints about whether it’s possible that life can exist on Mars.”

CU-Boulder faculty, staff and students are leading the mission, providing science operations and directing education and public outreach efforts. CU’s LASP provided two of the instruments. MAVEN team members include the University of California Berkeley, Lockheed Martin and NASA’s Goddard Spaceflight Center.

Researcher Tess McEnulty spent years following the progress of MAVEN while getting her doctorate at the University of California Berkeley, hoping someday to work on the pioneering mission at CU-Boulder. Doctoral degree in hand, McEnulty is a postdoctoral researcher working at LASP where she will focus on analyzing the immense amount of data collected by MAVEN’s eight scientific instruments.

“We’re trying to learn what the early Mars climate was like and if it could have been habitable,” she says. “This is my dream job.”

Photo courtesy NASA/JPL-Caltech