Washington, June 6 : NASA has funded the development of tiny space engines that would use Earth's magnetic field instead of chemical propellants to zip around our planet.
According to a report in Discovery News, the device represents a new breed of satellites that could alter satellite physics and economies, with the idea being to create millions of cheap satellites the size of corn kernels to augment today's multi-million dollar, car-sized satellite armada.
Though a prototype of the device exploded while in orbit, the test wasn't a catastrophic failure, according to Mason Peck, a scientist at Cornell University and coauthor of a study on the satellite.
Since that recent trial, Peck and his colleagues at the University of Michigan and State University of New York, Binghamton, have successfully tested their propulsion system, which could speed satellites along at more than four and a half miles a second.
Peck and his colleagues argue this new kind of mini device could make satellite missions more affordable and feasible.
"You could launch a million of these things and if only one of them reached the goal the mission would be a success," said Peck.
The propellant-less satellite idea works a lot like a TV. A 'gun' at the back of the TV shoots out negatively charged electrons. As they speed towards the viewer, a magnet changes their direction.
On a planetary scale, the electron would be the satellite zooming around the magnet, in this case the Earth.
As the satellite zooms around the spinning Earth, it would experience a force, known as the Lorentz force, pushing it at an angle perpendicular to its direction. The satellite would steal a tiny bit of the Earth's energy to propel it forward.
"The Earth would essentially push the satellite along," said Peck.
To test their idea, the researchers put a test satellite into a vacuum chamber at SUNY Binghamton and then shot charged ions at the spacecraft, simulating conditions in outer space.
"As the charged ions flowed around the test satellite, its charged particles were whipped off like wet paint off an aircraft," said Peck.
Just because it doesn't use chemical propellants doesn't mean the satellite is fuel-less. Radioactive material, such as Americium 241, which emits charged particles, or electricity from solar panels or a battery, would be necessary to maintain the satellite's charge.
The only real test of a tiny satellite magnetic propulsion system will be an actual flight in outer space.
Peck and his colleagues hope to perform a Sputnik-style test in a few years, where a small radio beep from space would signal success.