Friday, 14 July 2000 21:19 (ET) Severe solar storm due Saturday BY DAN FALK, UPI Science News BOULDER, Colorado, July 14 (UPI) -- A violent eruption observed on the sun Friday will likely engulf the Earth in a severe solar storm on Saturday, scientists say. A large coronal mass ejection has sent a giant swath of electrically charged particles hurtling toward Earth, and astronomers say it will likely reach our planet on Saturday afternoon -- possibly disrupting power grids, communications networks, and satellites. "It may be the biggest event of this solar cycle," said Bill Murtagh of the Space Environment Center (SEC) in Boulder, Colorado. "It's certainly the biggest event we've had in ten years." Solar activity rises and falls over an 11-year cycle. The last "solar maximum" occurred in 1989, and we are now in the middle of another peak. While coronal mass ejections can occur at any time, the most intense events are seen at solar maximum. When this solar material reaches the Earth's magnetic field, known as the magnetosphere, it triggers solar storms (also called geomagnetic storms) as well as displays of auroras -- the "northern lights." The SEC recently introduced a scale for measuring the intensity of solar storms, from G1 (the least intense) to G5 (extreme). "The storm we're expecting tomorrow will be in the G4 to G5 category, so we're looking for severe to extreme conditions," Murtagh said. In March, 1989, at the peak of the last solar cycle, a solar storm knocked out the main power grid for the province of Quebec, plunging millions of people into darkness. Murtagh says "we can't rule out" a repeat of a large-scale blackout as a result of the current solar storm. Over the last few years, however, astronomers have made great strides in predicting solar activity-giving a "heads up" for solar storms as well as auroras. Spacecraft such as SOHO (for Solar and Heliospheric Observatory) constantly monitor the sun, while the ACE satellite (for Advanced Composition Explorer), located between the Earth and the sun, detects any Earth-bound particles about 45 minutes before they reach our planet. That's enough of a warning for power companies to reduce the load on vulnerable circuits, or, alternatively, to add power to the system. "I think that's the good news of this solar cycle," said John Kappenman of Metatech Corp. in Duluth, Minn. "Technologies now exist to very accurately predict when these storms are going to occur, how severe they're going to be, and how much impact they're going to have." Kappenman cautions, though, that our power grids may be more vulnerable today that they were during the last solar maximum. Power companies now routinely transfer thousands of megawatts of electricity from one region to another along high-voltage lines. Such systems are especially vulnerable during solar storms, he says. "The collapse or failure of one grid can lead to a cascading chain, or a domino effect, rolling into neighboring systems," Kappenman said. "We were very lucky back in March of 1989 that worse things did not happen." While solar storms pose a very real threat to electrical systems, they can also trigger dramatic and often beautiful displays of aurora. Auroras are normally seen from high latitudes, such as the Canadian Arctic. During severe solar weather, however, such displays can be seen from much farther south. This weekend, auroras "will certainly be visible from mid-latitude states," Murtagh said. "If it's of the extreme variety, we could hear reports of aurora in southern states, even Florida." Updates on the solar storm can be found on the SEC's Web site (www.sec.noaa.gov). Bard <A HREF="http://www.ctrl.org/">www.ctrl.org</A> DECLARATION & DISCLAIMER ========== CTRL is a discussion & informational exchange list. Proselytizing propagandic screeds are unwelcomed. Substance—not soap-boxing—please! These are sordid matters and 'conspiracy theory'—with its many half-truths, mis- directions and outright frauds—is used politically by different groups with major and minor effects spread throughout the spectrum of time and thought. That being said, CTRLgives no endorsement to the validity of posts, and always suggests to readers; be wary of what you read. CTRL gives no credence to Holocaust denial and nazi's need not apply. Let us please be civil and as always, Caveat Lector. ======================================================================== Archives Available at: http://peach.ease.lsoft.com/archives/ctrl.html <A HREF="http://peach.ease.lsoft.com/archives/ctrl.html">Archives of [EMAIL PROTECTED]</A> http:[EMAIL PROTECTED]/ <A HREF="http:[EMAIL PROTECTED]/">ctrl</A> ======================================================================== To subscribe to Conspiracy Theory Research List[CTRL] send email: SUBSCRIBE CTRL [to:] [EMAIL PROTECTED] To UNsubscribe to Conspiracy Theory Research List[CTRL] send email: SIGNOFF CTRL [to:] [EMAIL PROTECTED] Om