Goblin Grin

Looking like a ghoulish Halloween mask in this winning photo, the so-called N44 superbubble shines in vibrant color thanks to Manuel Mejas from Argentina, who processed raw data from the Very Large Telescope to create the scene.
The superbubble is a nebula complex 160,000 light-years away in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. The bubble itself measures about 325 light-years across. Astronomers suspect the bubble was carved by fast stellar winds blown by a central cluster of stars. Additional star formation is thought to be triggered by the expanding gas shells of superbubbles such as this one.

Cratered Crescent

Although ESO collected almost a hundred entries during the Hidden Treasures contest, this winning picture of a crescent moon was the only submission featuring a solar system body.
The bane of most professional astronomers, the moon is often avoided because its bright glare blocks out views of more distant—and thus fainter—objects.
Andy Strappazzon from Belgium used raw data from a wide-field imager attached to the 2.2-meter telescope in Chile to assemble the complex and detailed mosaic of the cratered surface of Earth's only natural satellite. (See the first high-resolution pictures of the moon from NASA's Lunar Reconnaissance Orbiter.)
"We appreciated he looked for images of the moon, which are uncommon in our archive and which are very often overlooked," ESO's Sandu said.

Loops of Light

A mushrooming cloud of hydrogen gas—lighted up by dozens of young stars huddled near the cloud's center—spreads into interstellar space in this prize-winning picture of the nebula NGC 3582. The raw data came from the 2.2-meter La Silla telescope.
Like the contest's other cosmic artisans, Joe DePasquale of the United States had his work cut out dealing with optical distortions and digital blemishes scattered throughout the original data sets. Many raw images taken by even the largest telescopes contain such artifacts, which are caused by the instruments and so don't reflect the true natures of the featured objects.
Certain photo-processing techniques are required to correct the raw data, including using some reference and calibration images acquired before or after the desired image is snapped.
"These steps are delicate, as applying the wrong correction will result in an image that will have a very uneven background, stripes, lines, and other incorrect—and ugly—results," Sandu said.

Star Nest

Josh Barrington of the United States managed to render a hauntingly beautiful, prize-winning view of a distant cousin of the Orion Nebula, the star-forming nebula NGC 2467. Like a cosmic nest of stellar chicks, this cloud of dust and gas hides a cluster of newborn stars from direct view.
Barrington found the raw data—of an object 13,000 light-years from Earth—among images captured by a wide-field camera attached to the 2.2-meter La Silla telescope.
"The participants certainly exceed all our expectations," Sandu said. "This was not a competition for the faint-hearted, and entrants had to prove both knowledge of data processing and an artistic eye. We were pleasantly surprised to see so many talented people and, what's more, to discover that many of them learned to achieve such great results along the way."