Wednesday, 28 December 2011

Sun Storms May Super-Charge Northern Lights Wednesday


Particles ejected by recent solar storms are due to slam into Earth over the next few days, possibly causing super-charged northern lights displays and temporary radio blackouts in some areas, experts say.
On Monday (Dec. 26), the sun unleashed a massive eruption of solar plasma known as a coronal mass ejection (CME). The CME's fast-moving charged particles should squarely strike Earth's magnetic field at about 3:20 p.m. EST (2020 GMT) Wednesday, give or take seven hours, according to the websiteSpaceweather.com.
The particles from another CME could deliver a glancing blow to our planet a few hours earlier on Wednesday, Spaceweather.com reported.
The two impacts will likely spawn minor and/or moderate geomagnetic storms at high latitudes on Wednesday and Thursday. If they're powerful enough, geomagnetic storms can temporarily disrupt GPS signals, radio communications and power grids.
"Category G1 (Minor) geomagnetic storms are expected 28 and 29 December due to multiple coronal mass ejection arrivals," the National Oceanic and Atmospheric Administration's Space Weather Prediction Center wrote in an update Tuesday (Dec. 27). "R1 (Minor) radio blackouts are expected until 31 December."
Geomagnetic storms can also trigger dramatic aurora displays, which are also known as the northern and southern lights. So skywatchers at higher latitudes may want to look up after sunset over the next few days.
The sun's recent eruptions are part of a pattern.
After remaining surprisingly quiet from 2005 through 2010, our star has come alive in 2011, spouting off numerous powerful flares and CMEs. An August flare, for example, was the strongest one seen in more than four years.
Most experts expect such outbursts to continue over the next few years. Solar activity waxes and wanes on an 11-year cycle, and scientists think the current one — known as Solar Cycle 24 — will peak in 2013.


CMEs TARGET EARTH, MARS: The odds of a geomagnetic storm on Dec. 28th are improving with the launch of two CMEs toward Earth in less than 24 hours. NASA's STEREO-B spacecraft photographed this one on Dec. 26th:


According to a forecast track prepared by analysts at the Goddard Space Weather Lab, the cloud should squarely strike Earth's magnetic field on Dec. 28th at 20:22 UT (+/- 7 hours). Another CME could deliver a glancing blow a few hours earlier on the same date. The double impact is expected to spark mild-to-moderate geomagnetic storms at high latitudes.

 Aurora alerts: textvoice.
Mars is also in the line of fire. The first of the two CMEs is squarely directed toward the Red Planet--estimated time of arrival: Dec. 30th at 1800 UT. Using onboard radiation sensors, NASA's Curiosity rover might be able to sense the CME when it passes the rover's spacecraft en route to Mars.