

This full-disk multi-wavelength extreme ultraviolet image of the sun taken by the Solar Dynamics Observatory (SDO) on March 30, 2010. False colors trace different gas temperatures. Reds are relatively cool at 107,540 degrees Fahrenheit; blues and greens are hotter at 1,799,540 degrees Fahrenheit.
This NASA photo shows an extreme ultra-violet photo taken by Solar Dynamics Observatory (SDO) of gigantic plasma eruptions, sizzling gas swirls and turbulent magnetic field of the sun. US space agency NASA's SDO sent the first exposures of the sun to earth.
The electrically charged particles ejected from the sun travel toward Earth at 500 miles per second because they surf magnetic waves in the sun's outer atmosphere, NASA researchers report, based on a experiment conducted during John Glenn's space shuttle mission in 1998. Shown here is the solar corona during a 1998 total solar eclipse.
This is a mosaic of the extreme ultraviolet images from STEREO's SECCHI/Extreme Ultraviolet Imaging Telescope taken on Dec. 4, 2006. These false color images show the sun's atmospheres at a range of different temperatures. Clockwise from top left: 1 million degrees C, 1.5 million C, 60,000-80,000 C, and 2.5 million C.
This NASA image, captured on February 1, 2003, by astronauts aboard Space Shuttle Columbia on mission STS-107, shows the sun's airglow above Earth's horizon.
NASA's SDO (Solar Dynamics Observatory) photographed a large solar flare on Feb. 13.
This NASA image, obtained on October 20, 2010, shows the space agency's Solar Dynamics Observatory, or SDO, during its first lunar transit on October 7. The moon passed directly between the spacecraft (in its geosynchronous orbit) and the sun. With SDO watching the sun in a wavelength of extreme ultraviolet light, the dark moon created a partial eclipse of the sun.
A JHU/APL undated handout picture shows the NASA 'Solar Probe Plus' spacecraft, which is to be sent to the sun's outer atmosphere until 2018. The spacecraft will repeatedly sample the near-Sun environment, which has never been examined by a spacecraft before. The sun's corona is 140 million kilometers from the Earth.
This NASA image obtained October 21, 2010 shows a fast-growing sunspot 1112, crackling with solar flares. So far, none of the blasts has hurled a substantial CME, or coronal mass ejection, toward Earth. In addition, a vast filament of magnetism is cutting across the sun's southern hemisphere. This filament is so large it spans a distance greater than the separation of Earth and the moon.
This NASA photo taken by STS-129 crew members aboard the International Space Station shows the Sun as it rises over Earth's horizon, on Nov. 22, 2009.
A NASA spacecraft has discovered that the sun is not a perfect sphere. The RHESSI spacecraft measured the roundness of the sun with unprecedented precision and found that the star is not perfectly round as previously thought. The research claims that years of high solar activity caused the sun to develop a thin 'cantaloupe skin' that significantly increases its apparent oblateness - meaning its equatorial radius becomes slightly larger than its polar radius.
This photo shows the sun during one of its strongest eruptions in a UV shot by NASA's STEREO spacecraft.
In addition to giving off light and heat during solar flares, the Sun sends out clouds of particles and other emissions.
A sunspot with streamers of super-hot, electrically charged gas (plasma) arcs from the surface of the Sun, revealing the structure of the solar magnetic field.
The Moon passes in front of the sun on Feb. 25 2007, showing solar corona.