2014 is a peak year in the 11-year cycle of solar flares. While the radiation from flares poses little direct threat to people on Earth, the flares can disrupt signals or influence what we see in our night skies.
On March 12 at 6:34 p.m. Eastern Daylight Time (EDT), a mid-level solar flare was emitted from an active region of the sun. Solar flares occur when magnetic energy becomes kinetic energy, and there is a release of radiation. The radiation from this mid-level (M-class) flare didn’t directly harm anyone due to the Earth’s protective atmosphere, although typically M-class flares disrupt Global Positioning Systems (GPS), radio, and other communications. A potential concern is for astronauts in orbit; if caught outside during a solar flare, an astronaut would likely face radiation poisoning.
Solar flares happen on an 11-year cycle, and this is the peak year of Solar Cycle 24. The most intense flares, called the X-class, are more likely to occur throughout 2014 as sunspots release energy. X3 flares are three times as intense as X1 flares. For humans, the direction is more often a concern than intensity: an M-Class or X-Class flare pointed at Earth could create massive blackouts and grid damage.
According to NASA, a 1989 solar flare pointed toward the Earth caused a magnetic storm that tripped lines of generators in Quebec. This massive power outage occurred during the winter and took more than nine hours to restore. Damage was estimated at $6 billion. When the X-storms are focused away from Earth, as was an X28 storm in November 2003, the damage is much less severe.
Sometimes, coronal mass ejections are released from the sun alongside these flares. These coronal mass ejections are made up of large amounts of gas with magnetic field lines, exploded from the sun’s corona. Due to the increased activity on the sun’s surface, coronal mass ejections are often more common in the peak year of the 11-year cycle. When the ejections hit the Earth’s magnetic field, the charged particles collide a day later to create the Aurora Borealis. The Aurora Borealis, also called the Northern Lights, show beautiful reds, yellows, and greens in high latitude areas. When there are larger mass ejections, even southern latitude areas, such as Boston, Chicago, and Seattle, may see the auroras.
To find out more about recent solar flares and coronal mass ejections, visit NOAA’s Space Weather Prediction Center.