Solar Storm Near Earth Caused by Fast CME

Upon interacting with the giant magnetic bubble surrounding Earth, the magnetosphere, the CME caused a kind of solar storm known as a geomagnetic storm. The storm initially caused a mild storm rated on NOAA’s geomagnetic storm scales as a G2 on a scale from G1 to G5, and subsequently subsided to a G1. In the past, storms of this strength have caused auroras near the poles but have not disrupted electrical systems on Earth or interfered with GPS or satellite-based communications systems.

NOAA's Space Weather Prediction Center (http://swpc.noaa.gov) is the United States Government official source for space weather forecasts. For this storm, they predict:

“Potential Impacts: Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.

Induced Currents – Weak power grid fluctuations can occur.
Spacecraft – Minor impact on satellite operations possible.
Aurora – Aurora may be visible at high latitudes, i.e., northern tier of the U.S. such as northern Michigan and Maine.”

On March 15, 2013, at 2:54 a.m. EDT, the sun erupted with an Earth-directed coronal mass ejection (CME), a solar phenomenon that can send billions of tons of solar particles into space and can reach Earth one to three days later and affect electronic systems in satellites and on the ground. Experimental NASA research models, based on observations from the Solar Terrestrial Relations Observatory (STEREO) and ESA/NASA’s Solar and Heliospheric Observatory, show that the CME left the sun at speeds of around 900 miles per second, which is a fairly fast speed for CMEs. Historically, CMEs at this speed have caused mild to moderate effects at Earth.

The NASA research models also show that the CME may pass by the Spitzer and Messenger spacecraft. NASA has notified their mission operators. There is, however, only minor particle radiation associated with this event, which is what would normally concern operators of interplanetary spacecraft since the particles can trip on board computer electronics.

Not to be confused with a solar flare, a CME is a solar phenomenon that can send solar particles into space and reach Earth one to three days later. Earth-directed CMEs can cause a space weather phenomenon called a geomagnetic storm, which occurs when they connect with the outside of the Earth's magnetic envelope, the magnetosphere, for an extended period of time. In the past, geomagnetic storms caused by CMEs such as this one have usually been of mild to medium strength.

NOAA's Space Weather Prediction Center (http://swpc.noaa.gov) is the United States Government official source for space weather forecasts, alerts, watches and warnings.

What is a CME?

For answers to this and other space weather questions, please visit the Spaceweather Frequently Asked Questions page.

Karen C. Fox
NASA Goddard Space Flight Center, Greenbelt, MD