Categories: Saturn

Strange Radio Emissions from Saturn

Image depicting radio emissions at Saturn. Image credit: NASA/JPL/University of Iowa. Click to enlarge
Saturn’s radio emissions could be mistaken for a Halloween sound track.

That’s how two researchers describe their recent findings, published in the July 23 issue of the Geophysical Research Letters. Their paper is based on data from the Cassini spacecraft radio and plasma wave science instrument. The study investigates sounds that are not just eerie, but also descriptive of a phenomenon similar to Earth’s northern lights.

“All of the structures we observe in Saturn’s radio spectrum are giving us clues about what might be going on in the source of the radio emissions above Saturn’s auroras,” said Dr. Bill Kurth, deputy principal investigator for the instrument. He is with the University of Iowa, Iowa City. Kurth made the discovery along with Principal Investigator Don Gurnett, a professor at the University. “We believe that the changing frequencies are related to tiny radio sources moving up and down along Saturn’s magnetic field lines.”

Samples of the resulting sounds can be heard at http://www.nasa.gov/cassini , http://saturn.jpl.nasa.gov and http://www-pw.physics.uiowa.edu/cassini/ .

The radio emissions, called Saturn kilometric radiation, are generated along with Saturn’s auroras, or northern and southern lights. Because the Cassini instrument has higher resolution compared to a similar instrument on NASA’s Voyager spacecraft, it has provided more detailed information on the spectrum and the variability of radio emissions. The high-resolution measurements allow scientists to convert the radio waves into audio recordings by shifting the frequencies down into the audio frequency range.

The terrestrial cousins of Saturn’s radio emissions were first reported in 1979 by Gurnett, who used an instrument on the International Sun-Earth Explorer spacecraft in Earth orbit. Kurth said that despite their best efforts, scientists still haven’t agreed on a theory to fully explain the phenomenon.

They will get another chance to solve the radio emission puzzle beginning in mid-2008 when Cassini will fly close to, or possibly even through, the source region at Saturn. Gurnett said, ?It is amazing that the radio emissions from Earth and Saturn sound so similar.?

Other contributors to the paper include University of Iowa scientists George Hospodarsky and Baptiste Cecconi; Mike Kaiser (currently at Goddard Space Flight Center, Greenbelt, Md.); French scientists Philippe Louarn, Philippe Zarka and Alain Lecacheux; and Austrian scientists Helmut Rucker and Mohammed Boudjada.

Cassini, carrying 12 scientific instruments, on June 30, 2004, became the first spacecraft to orbit Saturn. It is conducting a four-year study of the planet, its rings and many moons. The spacecraft carried the Huygens probe, a six-instrument European Space Agency probe that landed on Titan, Saturn’s largest moon, in January 2005.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter. The radio and plasma wave science team is based at the University of Iowa, Iowa City.

For information on the Cassini mission visit http://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini

Original Source: NASA News Release

Fraser Cain

Fraser Cain is the publisher of Universe Today. He's also the co-host of Astronomy Cast with Dr. Pamela Gay. Here's a link to my Mastodon account.

Recent Posts

Astronomers Find a 3 Million Year Old Planet

Astronomers have just found one of the youngest planets ever. At only 3 million years…

3 hours ago

There was Hot Water on Mars 4.45 Billion Years Ago

Mars formed 4.5 billion years ago, roughly the same time as the Earth. We know…

7 hours ago

Axion Dark Matter May Make Spacetime Ring

Dark matter made out of axions may have the power to make space-time ring like…

11 hours ago

Earth’s Old Trees Keep A Record of Powerful Solar Storms

Most of the time the Sun is pretty well-mannered, but occasionally it's downright unruly. It…

1 day ago

New Supercomputer Simulation Explains How Mars Got Its Moons

One mystery in planetary science is a satisfying origin story for Mars's moons, Phobos and…

1 day ago

The Early Universe May Have Had Giant Batteries of Dust

The largest magnetic fields in the universe may have found themselves charged up when the…

1 day ago