A Coronal Mass Ejection Erupts From the Sun

A small, Earth-directed Coronal Mass Ejection erupted early this morning.

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The second of two coronal mass ejections (CMEs) on Jan. 23, 2013.

Sun Shoots Out 2 Coronal Mass Ejections

One of the two slow-moving ejections from Jan. 23 is Earth-directed. In the past, CMEs of this speed have not caused substantial geomagnetic storms.

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This triptych shows a coronal mass ejection or CME as it burst off of the sun in the morning of Jan. 13, 2013.

New Sunspots Producing Space Weather

On Jan. 13, 2013, at 2:24 a.m. EST, the sun erupted with an Earth-directed coronal mass ejection or CME. The CME left the sun at speeds of 330 miles ...

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About STEREO

STEREO (Solar TErrestrial RElations Observatory) is the third mission in NASA's Solar Terrestrial Probes program (STP). The mission, launched in October 2006, has provided a unique and revolutionary view of the Sun-Earth System. The two nearly identical observatories - one ahead of Earth in its orbit, the other trailing behind - have traced the flow of energy and matter from the Sun to Earth. STEREO has revealed the 3D structure of coronal mass ejections; violent eruptions of matter from the sun that can disrupt satellites and power grids, and help us understand why they happen. STEREO is a key addition to the fleet of space weather detection satellites by providing more accurate alerts for the arrival time of Earth-directed solar ejections with its unique side-viewing perspective.

› How STEREO Views the Entire Sun

News

Sungrazing Comets as Solar Probes

On Dec. 15, 2011, NASA's Solar Dynamics Observatory captured footage of Comet Lovejoy approaching the sun. The images and data collected by NASA's solar observing fleet can help scientists learn more about the sun itself.
NASA Spacecraft Observe Nov. 20 Solar Eruption

On Nov. 20, 2012, at 7:09 a.m. EST, the sun erupted with a coronal mass ejection.
STEREO Reaches Milestone At Sixth Anniversary

On Sept. 1, 2012, the two STEREO spacecraft and Earth were almost exactly equidistant, each with a direct view of a different third of the sun.
NASA's Solar Fleet Peers Into Coronal Cavities

By understanding the morphology, density and temperature of coronal cavities scientists can better understand eruptions on the sun and the space weather that can disrupt technologies near Earth.
SDO Sees Massive Filament Eruption

On September 1, 2012, a long, whip-like filament erupted on the sun. The eruption, called a coronal mass ejection, caused aurora near Earth on September 3.