May 23, 2013
M-Class Solar Flare And Two Coronal Mass Ejections Detected Mid-Week
Lawrence LeBlond for redOrbit.com - Your Universe Online
As the peak year of the solar maximum picks up in intensity, NASA´s Solar Dynamics Observatory (SDO) observed yet another solar flare and two coronal mass ejections (CMEs) mid-week. On Wednesday May 22 the sun emitted an M7 solar flare, which peaked at about 9:38 a.m. EDT.While it was not immediately clear if the M-class flare also produced a CME, NASA confirmed later that the flare was associated with a CME. While this CME was not Earth-directed, it has combined with an earlier CME, and the space agency said in a statement that the “flank of the combined cloud may pass Earth.”
Particles from CMEs cannot pass through the planet´s atmosphere and harm humans on Earth, but can affect electronic systems in satellites and on the ground. However, the radiation particles associated with these CMEs may affect the STEREO-B spacecraft and NASA has alerted operators.
NASA research models showed that the first CME began at 5:12 a.m. EDT, leaving the sun at about 400 miles per second. The second CME, associated with the M7 flare, began at 9:24 a.m. EDT, and left the sun at speeds approaching 745 miles per second.
Wednesday´s flare was in a class of generally weak solar flares. However, M-class flares can still cause some space weather effects near Earth, and in the past have caused brief radio blackouts at the poles. Harmful radiation from solar flares also cannot pass through the Earth´s atmosphere to affect humans. However, when strong enough, they can disturb GPS and communications signals around the planet. Such disturbances can last anywhere from minutes to hours depending on the size and duration of the flare.
An increased number of flares have been occurring as of late, as the sun is nearing the end of its solar maximum in the current 11-year activity cycle. The maximum is expected to peak in late 2013, transitioning to what is known as a solar minimum, with activity levels waning. Still, it is possible that activity levels could fluctuate, meaning we could see a decrease in activity during the maximum and perhaps an increase once the minimum begins.
Humans have been tracking the solar cycle continuously since it was discovered in 1843. NASA said that it is “normal for there to be many flares a day during the sun´s peak activity.”
NOAA´s Space Weather Prediction Center (SWPC) is the US government´s official source for space weather forecasts, alerts, watches and warnings. Further updates may be provided by NASA as they are available.