An expanding shell of debris called SNR 0519-69.0 is left behind after the explosion of a massive star in the Large Magellanic Cloud, a satellite galaxy to the Milky Way. The orbiting Chandra X-Ray Observatory detected the X-ray emissions from gas heated up to millions of degrees; those emissions are shown here in blue. The outer edge of the explosion (shown in red) and the stars in the field of view were seen in visible light from the Hubble Space Telescope. NASA released this picture on Jan. 22 to celebrate 2015 as the U.N. International Year of Light.
A United Launch Alliance Atlas 5 rocket blasts off from Cape Canaveral Air Force Station in Florida on Jan. 20, sending the MUOS-3 military telecommunication satellite into orbit. This long-exposure view looks over the campus of the Florida Institute of Technology in Melbourne, about 40 miles from the launch pad.
A four-image mosaic from a camera on the European Space Agency's Rosetta spacecraft shows a feature on Comet 67P/Churyumov-Gerasimenko on Jan. 16, from a distance of about 17 miles. The Rosetta probe is observing the comet as it zooms through space more than 300 million miles from Earth.
During NASA's Day of Remembrance on Jan. 28, NASA Administrator Charles Bolden and his wife Alexis Bolden place a wreath at the gravesites of Apollo 1 crew members Virgil Grissom and Roger Chaffee at Arlington National Cemetery. Grissom, Chafee and Ed White were killed in a launch-pad fire on Jan. 27, 1967. The annual Day of Remembrance honors the Apollo 1 crew, the astronauts of the 1986 Challenger explosion and the 2003 Columbia breakup, and others who lost their lives in space exploration efforts.
Comet Lovejoy streaks across the sky on Jan. 6 in an image captured by photographer Alan Dyer. Photographs reveal a greenish glow to the comet's coma, due to the presence of diatomic carbon and cyanogen. The comet was discovered last August by Australian amateur astronomer Terry Lovejoy.
SpaceX's Falcon 9 rocket lifts off on Jan. 10 from Cape Canaveral Air Force Station in Florida, sending a commercial Dragon cargo capsule to the International Space Station for a robotic resupply mission.
The SpaceX Dragon cargo craft approaches the International Space Station on Jan. 12 for its berthing. The Dragon brought more than 2.5 tons of supplies and experiments to the station.
Photos released on Jan. 6 show one of the most iconic Hubble Space Telescope images revisited: the Eagle Nebula's Pillars of Creation.
The visible-light picture on the left captures the multicolored glow of gas clouds, wispy tendrils of dark cosmic dust, and the rust-colored elephant trunks of the nebula's famous pillars.
On the right, near-infrared light transforms the pillars into eerie, wispy silhouettes, seen against a starry background. These new images provide a clearer view for astronomers who are studying how the structure of the pillars is changing over time.
An astronomical display takes place in the cloudless skies over La Silla's telescopes in Chile's Atacama desert, in an image released by the European Southern Observatory on Jan. 26.
The major players captured here are Comet Lovejoy, glowing green in the center of the image; the Pleiades above and to the right; and the California Nebula, providing some contrast in the form of a red arc of gas directly to the right of Lovejoy. A meteor adds yet another streak of light to the scene, seeming to plunge into the hazy pool of green light collecting along the horizon.
Astronaut Barry "Butch" Wilmore tweeted this image of the rising sun from the International Space Station on Jan. 3. The sun's glare is partially obscured by the station's robotic arm.
NASA astronaut Barry Wilmore looks out of the Cupola on the International Space Station on Dec. 28, 2014. The Cupola serves as a kind of control tower for operations outside the space station and gives the astronauts panoramic views of Earth.
The cometary globule CG4 glows menacingly in an image from the European Southern Observatory's Very Large Telescope, released on Jan. 28. Although it looks huge and bright in this image, the nebula is actually faint and not easy to observe. The exact nature of CG4 remains a mystery.
Four NASA suborbital sounding rockets are launched into an aurora from the Poker Flat Research Range in Alaska in this composite image from Jan. 26.
The interaction of solar winds and Earth's atmosphere produces northern lights, or auroras, that dance across the night sky and mesmerize the casual observer. However, to scientists, this interaction is more than a light display. It raises many questions about Earth's meteorological processes and the impact on the planet's atmosphere.
To help answer some of these questions, NASA suborbital sounding rockets carry university-developed experiments into auroras. The experiments study the atmosphere's response to auroral, radiation belt and solar energetic particles and associated effects on nitric oxide and ozone.
The largest Hubble Space Telescope image ever assembled provides a sweeping bird's-eye view of a portion of the Andromeda Galaxy. It's the sharpest large composite image ever taken of our galactic next-door neighbor. Astronomers released the 1.5 billion-pixel picture on Jan. 6.
Clear skies provide perfect conditions for seeing the waxing moon over Lengenfeld, Germany, on Dec. 26., 2014.
• The Year in Space Pictures 2014