In late December an active region on the sun spewed dozens of outbursts over a 36-hour period, including the bright flare and spout of plasma—charged gas—seen in this video still from NASA's Solar Dynamics Observatory.
The action was driven by strong magnetic forces on the sun's surface, which can pull against each other violently, triggering bursts of solar material that get hurled into space.
A new picture from the Hubble Space Telescope is the most detailed view yet of the core of M82, also called the Cigar galaxy. This tubular galaxy sits about 12 million light-years away in the constellation Ursa Major.
The colorized picture combines data from filters that let through light only from specific elements. In this case, the image shows light from gaseous sulfur (red), oxygen (green and blue), and hydrogen (cyan). That's why, in this image, darker dust lanes are silhouetted against the brightly glowing gas, while the galaxy's stars appear faint.
A shooting star graces the sky over the historic East Point Lighthouse in New Jersey in a picture taken during the 2012 Quadrantid meteor shower and submitted to National Geographic's My Shot.
The Quadrantids had a brief peak in the predawn hours Wednesday that was mostly visible to sky-watchers in North America.
Bright newborn stars glisten like dew in the rosy-hued core of M17, also called the Omega nebula. This newly released picture, from the European Southern Observatory's Very Large Telescope, is one of the sharpest views of Omega yet taken from the ground.
The nebula's dark dust and glowing gas are the raw materials for star formation, and Omega is one of the most active stellar nurseries for massive stars in the Milky Way.
As seen in this visible-light image, the nebula's hydrogen gas glows red to our eyes because it's being illuminated by intense ultraviolet radiation from the hot, young stars inside. This may be one reason another popular name for M17 is the Lobster nebula.
A newly released picture from NASA's MESSENGER spacecraft shows a collection of landforms called hollows around the central peaks of the impact crater Eminescu on the planet Mercury.
Hollows—shallow depressions sometimes surrounded by highly reflective material—were first described on Mercury last fall. Scientists think the unusual landforms could be evidence that tiny Mercury is still geologically active.
Like a forget-me-not in a field of snow, a small, bluish volcano pops up from the pale flanks of a larger one in Mars's Cerberus region, as seen in a colorized picture from NASA's Mars Reconnaissance Orbiter.
This region of Mars is dominated by the Cerberus Fossae troughs, long fissures on the red planet created when faults pulled apart the crust during the formation of the nearby Elysium volcanic field.
The smaller volcano's vent is aligned with one of these troughs, and ancient flows radiating away from the vent help give the peak its floral appearance.
Saturn's moon Tethys seems to hover under the planet's rings in a newly released picture from NASA's Cassini orbiter. Due to the angle of sunlight, the rings cast dark, wide shadows across the planet that help underscore the midsize moon.
Named for a Greek sea goddess, Tethys was discovered in the late 1600s by Italian-French astronomer Giovanni Domenico Cassini. Seen up close, the icy moon is heavily cratered and crisscrossed by troughs.