U-of-I physicist listens to distant Voyager

The most distant manmade object has crossed a new far-away boundary into interstellar space and a University of Iowa physicist is still listening as it phones home. NASA’s Voyager One was launched 28 years ago has crossed what’s called the “termination shock” at the far edge of our solar system — eight-point-seven billion miles from the sun. The U-of-I’s Don Gurnett says no spacecraft, or anything else made on Earth, has ever been so far away. Voyager is now 94 astronomical units away, or 94-times the distance between the Earth and the Sun. Gurnett is principal investigator for the spacecraft’s plasma wave gear which, even twice as far away as the planet Pluto, is still sending back valuable data every day. He says there’s a radioactive power supply onboard which should enable it to operate through 2020, perhaps longer. Gurnett says as Voyager voyages on into new territories, it becomes harder to hear its call.Radio waves take two seconds to reach the Moon from Earth. Gurnett says radio signals from Voyager now take nearly 13 hours to reach Earth. When interviewed by Radio Iowa, Gurnett was in New Orleans to present his findings during the spring 2005 meeting of the American Geophysical Union. Other sounds of Voyager’s encounters can be heard by visiting Gurnett’s Web site at: “www-pw.physics.uiowa.edu/space-audio/”.