Cameras enhance forecasting of sun-generated storms
Posted 7/16/2006
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by Michael P. Kleiman
Space Vehicles Directorate Public Affairs
7/16/2006 - KIRTLAND AIR FORCE BASE, N.M. (AFPN) -- Every 100-plus minutes, while orbiting approximately 50 miles above the Earth onboard the Coriolis satellite, the Solar Mass Ejection Imager experiment scans the darkness of space-seeking, sun-generated magnetic clouds of particles intent on striking the planet.
Since becoming operational in January 2003, the imager's three cameras have photographed more than 200 coronal mass ejections. Approximately 30 have reached Earth, causing a variety of problems including disruption of communication to the warfighter and damaging spacecraft components.
The imager's proof-of-concept experiment has enhanced forecasting when and where destructive clouds of solar particles will impact the Earth.
According to Janet Johnston, Solar Mass Ejection Imager program manager, the Solar Mass Ejection Imager project represents a collaborative effort that spans eight time zones.
"It has demonstrated that coronal mass ejections can be detected and tracked from the sun to the Earth and beyond," said Ms. Johnston, who is with the Battlespace Environment Division at Hanscom Air Force Base, Mass. "It has generated a data set never seen before. Lots of space weather forecasts are made, but the track record is not that good (60 percent are inaccurate). The Solar Mass Ejection Imager has demonstrated a 30-percent improvement in the accuracy of forecasts."
During the early 1990s, with an increasing reliance on satellites, the Department of Defense initiated space weather forecasts to protect its critical assets in the cosmos. Situated 93 million miles from the Earth, the sun periodically discharges large blobs of plasma and embedded electromagnetic fields, known as coronal mass ejections, traveling at speeds approaching 4 million miles per hour.
The fast and furious solar material can impact the Earth within one to three days after departure. They also trigger geomagnetic storms, which disrupt electric power and communication systems on Earth, as well as damage spacecraft circuitry and degrade performance.
In addition to monitoring solar storms, the Solar Mass Ejection Imager trial has observed high-altitude auroras, asteroids, debris, stellar variability and some unique comet tail disconnections. Nevertheless, after snapping pictures of space weather and other occurrences in the cosmos for the past three and a half years, the Solar Mass Ejection Imager has required little upkeep, but the radiation environment it operates in has impacted the quality of the images.
On the other hand, the Solar Mass Ejection Imager could remain operational for the next three to four years, or for as long as the Navy-administered Coriolis satellite continues its mission. That decision may be impacted by the shelf life of the spacecraft's other onboard payload, Windsat, a Naval Research Laboratory-sponsored experiment, which gathers information on the speed and direction of ocean-surface winds.
Regardless, Ms. Johnston says the Solar Mass Ejection Imager has set the benchmark for future space weather forecasting.
"We expect the Solar Mass Ejection Imager will continue to provide a great source of research," she said. "We also hope that an operational version of the Solar Mass Ejection Imager, which detects and tracks solar disturbances, will become a reality."
"It's part of the space weather forecasting ‘big picture.' To accomplish the task, in addition to reliable detection and tracking of coronal mass ejections, we will need particle sensors in orbit around the sun and methods to predict the incoming magnetic fields," Ms. Johnston said. "It will also require a fundamental understanding of the physics of solar processes.
"The imager definitely has aided the warfighter by providing improved space weather forecasts," Ms. Johnston said. "It also has drawn the defense community's attention to the importance of knowing when and where geomagnetic storms will happen.
"We are also making substantial progress in working with other space weather forecasters to employ the imager's results into prediction models," she said. "By combining Solar Mass Ejection Imager data with existing forecasting models, the experiment's observations can provide a ‘mid-course correction' for the coronal mass ejection that is heading toward the Earth."
The three charged couple devices camera trial involves a partnership between the National Aeronautics and Space Administration, the University of California at San Diego, Boston College, Boston University, Montana State University, the University of Birmingham in England, the Air Force's Space and Missile Systems Center and AFRL. |
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