A Stanford researcher claims to have discovered the reasoning behind why some satellites inexplicably fail without extensive or visible damage.
Although impacts with large space objects in space remain a potential cause, according to aeronautics and astronautics assistant professor Sigrid Close, the most likely cause of satellite failure is impacts from fast-moving micro-meteoroids known as “space dust” that turn into “a quasi-neutral gas of ions and electrons known as plasma” when they collide with other objects in space. Close theorized that this “plasma” has the potential to create an electromagnetic pulse that can damage and even completely disable any satellite it collides with.
“Spacecraft transmit a radio signal, so they can receive one that might potentially disable them,” Close said. “So, our question was: Do these plasmas emit radio signals, and if so, at what frequencies and with what power?”
During experiments at the Max Planck Institute for Nuclear Physics in Germany, researchers fired dust particles at speeds of 60 km/s towards targets representing satellites. The experiments confirmed that “when these particles hit, they create a plasma or quasi-neutral gas of ions and electrons, and that plasma can then emit in the radio frequency range,” Close said.
According to Close, the next step will be to prove that the effects occur similarly in space as they do in the laboratory, using an experiment being designed in cooperation with James Smith and Henry Garrett of NASA’s Jet Propulsion Laboratory.
Close believes that the discovery could help explain the loss of older satellites, such as the disappearance of the European Space Agency’s Olympus communication satellite in 1993, and could help to create design modifications that may better protect satellites from electronic systems failure in the future.
