A physicist and Medford graduate is drawing national attention over his controversial new theory that life on Mars was wiped out some 180 million years ago by a naturally occurring nuclear explosion.

A physicist and Medford graduate is drawing national attention over his controversial new theory that life on Mars was wiped out some 180 million years ago by a naturally occurring nuclear explosion.

Dr. John Brandenburg hypothesizes in his new book, "Life and Death on Mars: the New Mars Synthesis," that a nuclear reaction the equivalent of 1 million, 1-megaton hydrogen bombs could have wiped out life, oceans and atmosphere on Mars. He believes it could have occurred in the Mare Acidalium region, where there is a heavy concentration of radioactivity.

He bases his theory on a pattern of isotopes typical of nuclear explosions — radium, thorium and radioactive potassium — found on Mars. He believes these radio-isotopes also account for the planet's red color.

"Mars is a living planet. It had a large biosphere but the climate collapsed and there was a mass extinction," Brandenburg, a plasma physicist at Orbital Technologies in Madison, Wis., said in a telephone interview.

"The causes aren't clear. It also could have been caused by an asteroid hit. It's a dramatic and tragic story."

Brandenburg said natural nuclear reactions are possible and occurred billions of years ago in Gabon, Africa, where scientists believe a large uranium deposit spontaneously underwent nuclear fission.

Brandenburg, a graduate of then-Southern Oregon College, has presented his theories in conferences and journals and they were featured in a FoxNews.com story. But he concedes they are controversial and not accepted by mainstream science.

One such scientist, Dr. Terry Martin of Ashland, a retired planetary specialist who worked on Jet Propulsion Laboratory's Mars missions and is on the advisory board for ScienceWorks Hands-on Museum, said life is indeed possible on Mars but he's "not impressed" with Brandenburg's theories, which dismiss hundreds of research papers and decades of data by top scientists in the field.

"I dispute the evidence for 'radioactive substances covering the surface.' Where did he get such an idea? Not from the research I am familiar with. What 'nuclear catastrophe?'" Martin said.

"We have a perfectly straightforward explanation for why Mars is red: oxidation of iron in the soil, as is true here. Why spend another minute on these ideas from left field?"

From his three decades at JPL, working with the Viking mission to Mars, the Mars Global Surveyor and the Mars Reconnaissance Orbiter, Martin said there's a "good chance Mars had life billions of years ago."

Mars was pelted by comets, which are known to bring water to planets, and it could have had an atmosphere as good as Earth's, Martin said. Since Mars has 1/10th the mass of Earth, it would have cooled to livable temperatures much sooner, but with less gravity could have lost its atmosphere, warmth and water into space.

With meteors blasting chunks of Mars off into space — and some of them falling on Earth — this planet could well have been "seeded" with small organisms inside Martian rocks, Martin said, "in which case, we are the Martians."

Earth did better at retaining its life, Martin said, because, being bigger, our volcanism is still going on (providing heat), our gravity holds the atmosphere in place and our larger magnetic field shields life from harmful ions streaming from the sun.

Brandenburg said Martian maps clearly show an ocean shoreline with smoother terrain below the line and rough above. Martin said lots of scientists think that's possible but there's not 100 percent agreement on it.

While Brandenburg believes terraforming — making Mars Earthlike and growing a biosphere — is possible, Martin said it would be "really tough and take a long time" because water can't be transported there.

Martian rocks blown from the Red Planet have been discovered in Antarctica, noted Martin, but none are proven to have traces of life.

Enough scientists suspect life on Mars "or we wouldn't be sending these expensive Mars Rovers," Martin said. "We're searching for life because there's a chance of finding it and to see if it's habitable."

Martin is giving a talk at 7 p.m. Thursday (day has been corrected from earlier version), May 26, in the Meese Auditorium in the Art Building at Southern Oregon University. It's titled "Exploring Mars: What is So Special About Mars in Our History, Our Popular Culture and Our Scientific Focus." It's free and open to the public.

Both Martin and Brandenburg note that if there's life or fossils of life, they would likely be below the Mars surface.

Brandenburg graduated in 1971 from Medford Senior High School, where he built a laser for a science project, said his mother, Muriel Brandenburg, of Medford. He got his master's degree at University of California at Davis and his doctorate in theoretical plasma physics at UC extension with Lawrence Livermore National Laboratory.

Brandenburg is working on plasma propulsion, thought to be efficient for long-distance space travel. He has written two science fiction novels about the UFO coverup and a book about global warming impacts called "Dead Mars, Dying Earth" in 1999.

His late father, also named John Brandenburg, was a physician in Medford and a founder of Medford Clinic. The younger Brandenburg's brother, Daniel, is now a primary care physician in Medford, while his sister Molly is a cartoonist, writer and singer in Los Angeles.

John Darling is a freelance writer living in Ashland. Email him at jdarling@jeffnet.org.