Large solar flare likely disrupted radio systems in the Mideast
By
Bob Brewin
That event and a separate incident that forced officials to reroute commercial flights foreshadow future problems, scientist says.
The largest solar flare of the current sun weather cycle erupted in a blast of energy Tuesday that probably knocked out high-frequency radio communications systems in the Mideast, according to Joe Kunches, a space scientist with the National Oceanic and Atmospheric Administration's Space Weather Prediction Center in Boulder, Colo.
Tuesday's flare followed a coronal mass ejection over the weekend -- described by Kunches as a "big cloud" of charged particles -- that lasted about nine hours and caused some commercial airlines to reroute flights that go over the North Pole.
Polar flights cannot access communications satellites, which operate in a geostationary orbit over the equator, and instead have to rely on HF radio, which can be blacked out by sun-caused magnetic storms, he said. HF radios are also used by military special forces units and Marine and Air Force forward air controllers for long-range communications.
NASA, which eyeballed today's solar flare with its Solar Dynamics Observatory satellite, described it as the largest of the current 11-year solar cycle and three times bigger than the previous large flare on Feb. 11. Kunches said this was the largest flare since 2006.
The flare and the coronal mass ejection over the weekend foreshadow events to come as the current solar cycle peaks in 2013, he added. The sun can produce massive geomagnetic storms that can knock out power grids, as happened in March 1989, when current from the sun knocked out a transformer in the Hydro-Quebec power grid in Canada, causing a nine-hour blackout.
Radio waves pass through the ionosphere, located about 60 miles above Earth, and Kunches said magnetic storms distort this layer to such an extent that GPS receivers either report false position information or black out completely. Solar storms have in in the past knocked out the Wide Area Augmentation System used by the Federal Aviation Administration to improve the accuracy and reliability of GPS.
The Space Weather Center uses a number of satellites besides the Solar Dynamics Observatory to develop its forecasts , including four NOAA Geostationary Operational Environmental Satellites and the Solar and Heliospheric Observatory, a joint NASA and European Space Agency satellite for imagery, Kunches said. Space weather forecasters also use supercomputers operated by the National Weather Service for modeling, he said.
For near-term warning of geomagnetic storms, Kunches said space weather forecasters rely on NASA's Advanced Composition Explorer satellite, located 1.5 million miles from Earth, to track the solar wind, which can generate magnetic storms that can cripple communications and power systems. But that provides only about a one-hour warning.
Michael Hesse, chief of the of Space Weather Lab at NASA's Goddard Space Flight Center told a Space Weather forum this June that these spacecraft allow tracking of "solar storms in three dimensions as the storms bear down on Earth . . . This sets the stage for actionable space weather alerts that could preserve power grids and other high-tech assets during extreme periods of solar activity."
Kunches declined to predict space weather in 2013 and the effect on the power grid and communications systems. But he did say that it could end up as a test of the robustness of systems we usually take for granted.