One of the largest solar flares of this solar cycle erupted on 6 March, producing two coronal mass ejections (CMEs) as a result. NASA has predicted that the leading edge of the first CME would reach Earth at around 1.25am (EST) today, plus or minus seven hours, producing a severe geomagnetic storm that could spark possible disruptions to high-frequency radio communications, GPS and power grids.
The space agency said such a CME would also induce auroras, similar to the Northern Lights, at low latitudes.
NASA has revealed the latest information on the sun’s solar activity and the CMEs of this week based on data from the Solar Terrestrial Relations Observatory (STEREO) and the Solar Heliospheric Observatory.
It said today that the first CME has been travelling faster than 1,300 miles per second, while the second CME is travelling at more than 1,100 miles per second.
Impact Earth, Mars and pass by spacecraft
In its latest update, NASA said its models were predicting the CMEs would impact both Earth and Mars, as well as passing by several NASA spacecraft, including Messenger, Spitzer, and STEREO-B.
It said it expected the leading edge of the first CME to reach Earth at about 1.25am EST on the morning of 8 March (plus or minus seven hours).
And as well as the CME impact potentially producing a "severe geomagnetic storm" that could impact power grids, GPS and HF radio communication, NASA also alluded to how those in low latitudes could also be in for an aurora treat.
This image is from the 6 March 2012 X5.4 flare, captured by the Solar Dynamics Observatory (SDO) in the 171 Angstrom wavelength. Credit: NASA/SDO/AIA
On 6 March, the sun erupted with one of the largest solar flares of this solar cycle.
NASA categorised this flare as an X5.4, making it the second-largest flare after an X6.9 solar flare on 9 August 2011.
The current increase in the amount X-class flares is part of the sun’s normal 11-year solar cycle. The sun is gearing up for its solar maximum, which is expected to peak in late 2013, which is why the planet is experiencing such increased solar activity of late.
Also on 6 March, the same region of the sun erupted with an X1.3 class flare. An X1 is five times smaller than an X5 flare, according to NASA.
NASA said today that before the 6 March solar activity, the region had already produced numerous M-class and one X-class flare.
It said that the region continues to rotate across the front of the sun, so the 6 March flare was more Earthward facing than the previous ones.
"It triggered a temporary radio blackout on the sunlit side of Earth that interfered with radio navigation and short-wave radio," said the space agency.
‘Dumping’ of solar particles and magnetic fields
NASA said that CME associated with the X-class flare from 4 March has already "dumped solar particles and magnetic fields" into the Earth’s atmosphere, distorting the planet’s magnetic fields and causing a moderate geomagnetic storm, rated a G2 on a scale from G1 to G5.
"Such storms happen when the magnetic fields around Earth rapidly change strength and shape. A moderate storm usually causes aurora and may interfere with high frequency radio transmission near the poles. This storm is already dwindling, but the Earth may experience another enhancement if the most recent CMEs are directed toward and impact Earth," added NASA.