May 19, 2013
Sun Activity Increases, Coronal Mass Ejection Heads For Earth
[WATCH VIDEO: Coronal Mass Ejection On May 17, 2013]
Lawrence LeBlond for redOrbit.com - Your Universe Online
On May 17, the sun unleashed an Earth-directed coronal mass ejection (CME) at 5:24 a.m. EDT sending billions of tons of solar particles into space. The matter from this CME will likely reach Earth in one to three days and potentially affect electronic systems in satellites and possibly the International Space Station (ISS).
NASA research models based on observations from NASA´s Solar Terrestrial Relations Observatory show that the CME left the sun and was traveling at about 745 miles per second. While it is unlikely that this CME will produce a sizeable geomagnetic storm, one that can wreak havoc on satellites, electrical systems aboard the ISS and even systems here on Earth, it could still cause some disruptions.
NASA said it will continue to monitor the situation and provide further updates if needed.
This is only the tip of the proverbial iceberg in a huge sea of CMEs and solar flares that have been picking up on the surface of the sun this year.
In December, redOrbit´s Lee Rannals reported that the Sun was gearing up for a solar maximum in 2013, reaching its peak activity in the summer and fall months. So far, the sun has not let anyone down, as it has been pumping out solar flares and CMEs left and right for the past few months.
The solar maximum is the peak in the sun´s 11-year cycle of increased activity. This cycle, which can last anywhere from 9 to 14 years is followed by what is called a solar minimum, where the sun´s activity wanes. However, activity can be minimal during maximums and maximal during minimums and it´s really anybody´s guess when the sun is going to unleash all its fury or purr like a kitten.
While the solar maximum was upon us, the first few months of 2013 had been rather quiet for the sun with little to no activity to speak of. In March, researchers from NASA´s Goddard Space Flight Center said there was an explanation for this and was eager to share.
Dean Pesnell, a solar physicist at Goddard, explained that the sun was actually double peaking, meaning it was going through two solar maximums. Apparently there was a mini-max in 2011 with more solar spot and solar storm activity, leading some to believe that 2011 was the true year for the maximum.
However, this is not the first time astronomers have observed such a fluctuation in the cycles. There were in fact double peaks in the 1989 and 2001 solar maximum years as well, where activity peaked, waned and then peaked again.
Perhaps showing the ability of experts to forecast space weather and solar activity with reasonable exactness, the NOAA/NASA Solar Cycle Prediction panel forecast the solar activity to pick up in May of 2013. And while the sun did have an increased level of activity in April, when the sun produced three coronal mass ejections in the course of two days, the best show so far occurred in May.
Less than a week ago the sun produced its first X-class solar flare of 2013, followed not by one, but three more X-class flares within 24 hours. The first, an X1.7 flare, occurred on May 13 at 2:31 UT. That flare, as impressive as it was, was succeeded by an X2.8 flare less than 15 hours later and then an even larger X3.2 flare at 1:46 UT on May 14. The final X-class flare, a smallish X1.2 flare, occurred 15 minutes later at 2:01 UT, marking four X-class flares in less than 24 hours.
While these flares were very impressive, it is important to note that all four occurred on the side of the sun not facing Earth. While radiation from such flares does not pose a risk to humans on Earth when they are directed at us, they can cause some minor disruptions to manmade satellites, GPS signals, telecommunications and even the ISS, including humans working aboard the station.
While solar flares do not pose as much of a risk to Earth, the coronal mass ejections that usually follow solar flares can be another story altogether. Massive CMEs have the potential to cause powerful geomagnetic storms and in the past have been known to cause significant damage to electrical systems on Earth.
As reported in Rannals' December article, the largest known CME ever to hit earth occurred in 1859 and disrupted the telegraph system at the time. If we factor in today´s technology, a CME of that size could have the potential to cause 10, or even 100, times the amount of damage that was caused 150 years ago.
A CME that occurred in 1972 was powerful enough to cause a geomagnetic storm that damaged phone lines in Illinois. And a 1989 event melted transformers in New Jersey and knocked out power for most of Quebec.
While this past week´s CME has the potential to cause some disruptions, it is unlikely that it will rival that of the 1859, 1972 or 1989 events.
NASA´s Solar Dynamics Observatory (SDO) is the main sun monitoring system for detecting solar flares and coronal mass ejections. It has been monitoring the sun since its launch date on February 11, 2010.
NOAA´s Space Weather Prediction Center (SWPC) is the US government´s official source for space weather forecasts, alerts, watches and warnings.