Asteroids, fireballs and airport delays were the topics of conversation at the Sunflower Theatre on Thursday.
As part of the theatre’s Ideas and Lecture Series, local space expert Ray Williamson spoke to a packed house in a presentation titled “America’s Little-Known Civilian Space Efforts: Observing, Detecting, Warning.” Williamson, a former astronomy professor and analyst in the U.S. Office of Technology Assessment, went over some of the work being done by organizations in the country that put satellites in space but don’t always get much attention from the public. The work done by those satellites can range from finding lost airplanes and ships, to predicting “space weather,” to making everyday things like ATM transactions possible.
Williamson started the lecture by saying he didn’t plan to talk about manned space flight, even though that’s the first thing that comes to most people’s minds when they think about human activity above the atmosphere.
“I want to introduce ... some space agencies you might not know about, not because they’re secret, but because people just don’t know about them,” Williamson said. “I feel like programs like I’m going to talk about tonight are really focused on bringing benefits back to Earth.”
In addition to NASA, he mentioned the National Oceanic and Atmospheric Administration, the U.S. Geological Survey and the National Security Agency as examples of government organizations that operate satellites for various reasons. One of those reasons is search and rescue. Satellites can track the electric beacons that are installed on most ships and aircraft, as well as the personal kind that hikers and skiers carry into wilderness areas. Williamson said search and rescue is one of the areas where U.S. space agencies cooperate the most with other countries.
But one of the most important things satellites track and observe, according to the presentation, is space weather. Solar flares, meteorites and other extraterrestrial phenomena can wreak havoc on planet Earth and the infrastructure of the people who live here. As an example, Williamson talked about the major solar flares in September 1859 that caused the Northern Lights to be visible as far south as India and destroyed telegraph machines across the United States. Even today, some airplanes won’t fly during solar storms, and solar activity sometimes knocks out power grids.
He also told the story of the Tunguska Event, an explosion that took place over Siberia in 1908, flattening more than 1,000 square miles of forest. For a long time, its cause was uncertain, but Williamson said scientists today believe the explosion was a shock wave from a huge asteroid burning up in the atmosphere. It’s estimated to have created up to 300 times the energy of the atomic bomb explosion at Hiroshima.
Satellites can help the government detect these disasters in advance, but they still have a long way to go in learning how to prevent them, Williamson said. One way to stop a large asteroid from hitting Earth would be to use a satellite to affect its gravity and move it off course, or to propel it away with an explosion. But Williamson said the world still needs an international group that could authorize such a mission if it ever became necessary.
“These are rare events,” he said of Tunguska-size asteroids. “It’s probably not going to happen in our lifetimes, but it is probably going to happen someday, and NASA is working on what to do when it does.”
The theatre was full Thursday night, which was good for KSJD Radio, which set up a table for donations after the lecture. The event itself was free, like all the other entries in the lecture series, although a $5 donation was encouraged. Several audience members engaged in discussion with Williamson afterward, especially about the effects of space weather on the planet and what people can do to minimize them.
The next entry in the Ideas and Lecture Series has not yet been announced.