<p>A long loop of plasma that had been snaking around the sun erupted on Monday, and <a id="es__" title="NASA's Solar Dynamics Observatory" href="http://sdo.gsfc.nasa.gov/">NASA's Solar Dynamics Observatory</a> was on hand to catch the action.</p><p>Known as a solar filament, the loop is a cloud of relatively cool gas held aloft by magnetic forces. Such features are unstable, though, and often break away from the sun.</p><p>The pictured filament grew extra long, according to NASA: It spanned almost 621,000 miles (a million kilometers) before snapping.</p>

Solar Snake

A long loop of plasma that had been snaking around the sun erupted on Monday, and NASA's Solar Dynamics Observatory was on hand to catch the action.

Known as a solar filament, the loop is a cloud of relatively cool gas held aloft by magnetic forces. Such features are unstable, though, and often break away from the sun.

The pictured filament grew extra long, according to NASA: It spanned almost 621,000 miles (a million kilometers) before snapping.

Image courtesy SDO/NASA

Space Pictures This Week: Sun Snake, Ice Curtain, More

A plasma loop erupts from the sun, Falcon 9 takes flight, Hubble spies a star-spangled "eagle," and more in the week's best space pictures.

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