Space weather `implicated` for satellite failures

Scientists suspect that space weather may be the culprit behind some satellite failures.

Washington: Scientists suspect that space weather may be the culprit behind some satellite failures.

Massachusetts Institute of Technology researchers are investigating the effects of space weather - like solar flares, geomagnetic storms and other forms of electromagnetic radiation - on geostationary satellites, which provide much of the world`s access to cable television, Internet services and global communications.

Geostationary satellites orbit at the same rate as the Earth`s rotation, essentially remaining above the same location throughout their lifetimes. These satellites are designed to last up to 15 years, during which time they may be bombarded by charged particles.

Most satellites cover sensitive electronics with layers of protective shielding, but over time, radiation can penetrate and degrade a satellite`s components and performance.

Whitney Lohmeyer, a graduate student in MIT`s Department of Aeronautics and Astronautics is working with Kerri Cahoy, an assistant professor of aeronautics and astronautics, to understand how sensitive components are to the weather conditions in space, and how space weather may contribute to failures.

For the study, the team analyzed space weather conditions at the time of 26 failures in eight geostationary satellites over 16 years of operation. The researchers found that most of the failures occurred at times of high-energy electron activity during declining phases of the solar cycle.

This particle flux, the scientists theorize, may have accumulated in the satellites over time, creating internal charging that damaged their amplifiers - key components responsible for strengthening and relaying a signal back to Earth.

The study has been published in the journal Space Weather.