Thursday, September 8, 2011

Solar Eruption Tuesday 6th Sept 2011 to reach earth Friday 9th of September 2011

WASHINGTON - U.S. forecasters say a new solar flare should provide only a glancing blow on Earth on Friday and is unlikely to cause any problems.

The National Weather Service's Space Weather Prediction Center says northern lights may be slightly more visible, but there should be no radio, satellite or electrical grid disruptions.

They say the flare that erupted from a sunspot Tuesday is fairly big, but most of it will miss Earth, going far above the planet. Senior forecaster Norm Cohen said the flare should arrive around 1:30 p.m. EDT Friday (1730 GMT), but is nothing to worry about.

Meanwhile, a new research is suggesting that solar flares last longer and are more powerful than thought.

"This new data will increase our understanding of flare physics and the consequences in near-Earth space where many scientific and commercial satellites reside," Lika Guhathakurta, lead program scientist for NASA's Living with a Star Program at the agency's headquarters in Washington, said in a statement. The paper detailing the results came out Wednesday in the online edition of the Astrophysical Journal. Source

NOAA / Space Weather Prediction Center (NOAA seem to disagree)

Space Weather Message Code: ALTEF3
Serial Number: 1843
Issue Time: 2011 Sep 08 1153 UTC

CONTINUED ALERT: Electron 2MeV Integral Flux exceeded 1000pfu
Continuation of Serial Number: 1842
Begin Time: 2011 Sep 07 1400 UTC
Yesterday Maximum 2MeV Flux: 1276 pfu

- A-index values >= 20, 30, 50, and 100

WARNINGS (Onset or Persistence, including Extensions):
- 10MeV Protons >= 10pfu;
- 100MeV Protons >= 1pfu; and
- K-index values = 4, 5, 6 and >= 7.

WARNINGS (single symbol only):
- Sudden Impulse

ALERTS (including Alert Continuations for Protons):
- X-ray Flux >= M5
- Type-II and Type-IV Radio Sweeps;
- 10MeV Protons >= 10pfu, 100pfu, 1Kpfu, 10Kpfu, 100Kpfu;
- 100MeV Protons >= 1pfu;
- 2MeV Electrons >= 1Kpfu
- K-index values = 4, 5, 6, 7, 8, 9
- Stratospheric Stratwarm

ALERTS appear for X-ray Flux >=M5 and over the course of Proton and K-index events, due to the rules that govern their issue. Since Proton events may be long-lived, CONTINUED ALERTS follow the initial alert near the beginning of each UT day, for the highest threshold in effect when such events remain in progress. Lower K-index values (K= 4 and 5) only require the issue of one initial ALERT per a corresponding valid warning period. However higher K-index values (6 and above) require an ALERT for each synoptic (3-hour) period they are observed, regardless of corresponding warning periods. Source