LAWRENCE — Several University of Kansas faculty members will appear on the episode “Gamma-ray Burst,” which is the second episode in the new Weather Channel series “Forecasting the End.” This episode is presently scheduled to air at 8:30 p.m. CDT on Thursday, March 21.
The KU researchers are Bruce Lieberman, professor of ecology and evolutionary biology; Adrian Melott, professor of physics and astronomy; and Brian Thomas, associate professor of physics and astronomy at Washburn University and adjunct associate professor at KU.
The series chronicles the sorts of natural disasters that occur only occasionally, but cause severe problems, including extinction of many species. Each episode of the series is devoted to one kind of catastrophic event.
The KU collaboration has focused on the kinds of events that are caused by influences from outside the Earth, particularly bursts of radiation. The researchers said that gamma-ray bursts are going off all the time — several per day in the observable universe. Such bursts accompany the death of a star, but in some unusual cases the radiation goes out in narrow jets that can cause damage to a planet thousands of light years away.
“One can show that the Earth should have been hit by such a jet multiple times during the geological past, from such a distance as to be a likely cause of a mass extinction — the sudden loss of a large fraction of the species that live on Earth,” said Melott.
Melott said mass extinctions have come on average around once per 25 million years.
The KU collaboration has advanced the idea that at least one mass extinction that occurred 445 million years ago — and one of the worst — fits the profile of what would be expected from a hit by a nearby gamma-ray burst. This involves the selective death of species that would be exposed to sunlight during part of their lives, a sudden glaciation, and a pattern of extinction that fits a burst that went off over the Earth’s south pole. The biggest effect damaging life on Earth is a great increase in ultraviolet radiation brought about by damage to the ozone layer resulting from the radiation.
The KU group has become the world leader in the analysis of possible damage to Earth by radiation bursts. In a January report on possible global disasters, the British journal Nature devoted one-third of its citations to work by the KU collaboration.
Thomas added that televising results of these kinds of scientific investigation has special value.
“TV is a great way to get science out of the lab and into peoples’ homes,” he said. “Many people who would never pick up a publication devoted to science reporting will see a show like this one. This gives them an opportunity to see scientists talking about our work in our own words, supported by engaging graphics and a story line. It’s vitally important that the public, which supports scientific research through their tax dollars, have an idea of what it is that we as scientists do, the kinds of questions we ask, and how we go about answering those questions.”