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Explanation: Brilliant Venus and the central Milky Way rise in the early morning hours of March 1 in this sea and skyscape. The scene looks out from a beach at Sea Isle City, New Jersey, USA, planet Earth. Of course, Earth orbits well within the solar system's habitable zone, that Goldilocks region not too close and not too far from the Sun where surface temperatures can support liquid water. Similar in size to Earth, Venus lies just beyond the inner boundary of the habitable zone. The watery reflection of light from our inhospitable sister planet is seen along a calm,...

Explanation: NGC 1333 is seen in visible light as a reflection nebula, dominated by bluish hues characteristic of starlight reflected by dust. A mere 1,000 light-years distant toward the heroic constellation Perseus, it lies at the edge of a large, star-forming molecular cloud. This striking close-up view spans about two full moons on the sky or just over 15 light-years at the estimated distance of NGC 1333. It shows details of the dusty region along with hints of contrasting red emission from Herbig-Haro objects, jets and shocked glowing gas emanating from recently formed stars. In fact, NGC 1333 contains hundreds...

Explanation: The eggs from this chicken may form into stars. The above pictured emission nebula, cataloged as IC 2944, is called the Running Chicken Nebula for the shape of its greater appearance. The image was taken recently from Siding Spring Observatory in Australia and presented in scientifically assigned colors. Seen near the center of the image are small, dark molecular clouds rich in obscuring cosmic dust. Called Thackeray's Globules for their discoverer, these "eggs" are potential sites for the gravitational condensation of new stars, although their fates are uncertain as they are also being rapidly eroded away by the intense...

Explanation: Dramatic prominences can sometimes be seen looming just beyond the edge of the sun. Such was the case last week as a large prominence, visible above, highlighted a highly active recent Sun. A waving sea of hot gas is visible in the foreground chromosphere in great detail as it was imaged in one specific color of light emitted by hydrogen. A solar prominence is a cloud of solar gas held just above the surface by the Sun's magnetic field. The Earth, illustrated in the inset, is smaller than the prominence. Although very hot, prominences typically appear dark when viewed...

Explanation: Is Earth the only known world that can support life? In an effort to find life-habitable worlds outside our Solar System, stars similar to our Sun are being monitored for slight light decreases that indicate eclipsing planets. Many previously-unknown planets are being found, including over 700 worlds recently uncovered by NASA's Kepler satellite. Depicted above in artist's illustrations are twelve extrasolar planets that orbit in the habitable zones of their parent stars. These exoplanets have the right temperature for water to be a liquid on their surfaces, and so water-based life on Earth might be able to survive on...

Explanation: What would it be like to see a sunset on Mars? To help find out, the robotic rover Spirit was deployed in 2005 to park and watch the Sun dip serenely below the distant lip of Gusev crater. Colors in the above image have been slightly exaggerated but would likely be apparent to a human explorer's eye. Fine martian dust particles suspended in the thin atmosphere lend the sky a reddish color, but the dust also scatters blue light in the forward direction, creating a bluish sky glow near the setting Sun. Because Mars is farther away, the Sun...

Explanation: Big, beautiful spiral galaxy NGC 7331 is often touted as an analog to our own Milky Way. About 50 million light-years distant in the northern constellation Pegasus, NGC 7331 was recognized early on as a spiral nebula and is actually one of the brighter galaxies not included in Charles Messier's famous 18th century catalog. Since the galaxy's disk is inclined to our line-of-sight, long telescopic exposures often result in an image that evokes a strong sense of depth. The effect is further enhanced in this sharp image by galaxies that lie beyond the gorgeous island universe. The background galaxies...

Explanation: Only two days past full, February's moon shines through thin clouds, rising on the left in this fisheye night skyscape. The moonlight illuminates a weathered, rounded foreground in the Alabama Hills, conveniently located east of Mt. Whitney along the Sierra Nevada range in California, USA, planet Earth. Orion the Hunter stands at the right, a familiar northern winter constellation. Bright Jupiter, the solar system's ruling gas giant, is near center at the top of the frame. Below Jupiter, Sirius, alpha star of the Big Dog, poses above a bowed and twisted landform known as Möbius Arch, its curve reminiscent...

Explanation: Venus now appears as planet Earth's brilliant morning star standing above the eastern horizon before dawn. For most, the silvery celestial beacon rose in a close pairing with an old crescent Moon on February 26. But seen from locations in western Africa before sunrise, the lunar crescent actually occulted or passed in front of Venus, also in a crescent phase. Farther to the east, the occultation occurred during daylight hours. In fact, this telescopic snapshot of the dueling crescents was captured just before the occultation began under an afternoon's crystal clear skies from Yunnan Province, China. The unforgettable scene...

Explanation: Sometimes the more you look at an image, the more you see. Such may be the case for this beautiful nighttime panorama taken last week in New Zealand. Visible right off, on the far left, are common clouds, slightly altered by the digital fusion of combining 11 separate 20-second exposures. More striking, perhaps, is the broad pink aurora that dominates the right part of the image, a less common auroral color that is likely tinted by excited oxygen atoms high in Earth's atmosphere. Keep looking and you might notice a bright light just beyond the mountain on the left....

Explanation: The well known Pleiades star cluster is slowly destroying part of a passing cloud of gas and dust. The Pleiades is the brightest open cluster of stars on Earth's sky and can be seen from almost any northerly location with the unaided eye. The passing young dust cloud is thought to be part of Gould's belt, an unusual ring of young star formation surrounding the Sun in the local Milky Way Galaxy. Over the past 100,000 years, part of Gould's belt is by chance moving right through the older Pleiades and is causing a strong reaction between stars and...

The shape of the Milky Way galaxy, our solar system's home, may look a bit like a snail, but spiral galaxies haven't always had this structure, scientists say. In a recent report, a team of researchers said they now know when and how the majestic swirls of spiral galaxies emerged in the unicerse. Galaxies are categorized into three main types, based on their shapes: spiral, elliptical and irregular. Almost 70 percent of those closest to the Milky Way are spirals. But in the early universe, spiral galaxies didn't exist. A husband and wife team of astronomers, Debra Meloy Elmegreen at...

Explanation: What would it look like to travel to the center of an active galaxy? Most galactic centers are thought to house black holes millions of times more massive than our Sun. The spaces surrounding these supermassive black holes may be far from dormant, however, flickering in many colors and earning the entire object class the title of Active Galactic Nuclei (AGN). Pictured above is a video illustrating how an active galactic nucleus may appear up close. AGN typically sport massive accretion disks feeding the central black hole, as well as powerful jets shooting electrically charged matter far into the...

Explanation: If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear. This is because Saturn's rings are confined to a plane many times thinner, in proportion, than a razor blade. In modern times, the robot Cassini spacecraft orbiting Saturn now also crosses Saturn's ring plane. A series of plane crossing images from 2005 February was dug out of the vast online Cassini raw...

In 2008, a group of astronomers led by Alex Parker did a study of the size distribution of asteroid families using data from the Sloan Digital Sky Survey. Asteroid families often have distinctive optical colors, the team said, and they were able to offer an improved way to separate out the family members into their colors. This resultant animation put together just this week by Parker shows the orbital motions of over 100,000 asteroids, with colors illustrating the compositional diversity and relative sizes of the asteroids. All main-belt asteroids and Trojan asteroids with orbits known to high precision are shown...

Explanation: A mere 600 light-years away, M44 is one of the closest star clusters to our solar system. Also known as the Praesepe or the Beehive cluster its stars are young though, about 600 million years old compared to our Sun's 4.5 billion years. Based on similar ages and motion through space, M44 and the even closer Hyades star cluster in Taurus are thought to have been born together in the same large molecular cloud. An open cluster spanning some 15 light-years, M44 holds 1,000 stars or so and covers about 3 full moons (1.5 degrees) on the sky in...

Explanation: The Lighthouse nebula was formed by the wind of a pulsar, a rapidly rotating, magnetized neutron star, as it speeds through the interstellar medium at over 1,000 kilometers per second. Some 23,000 light-years distant toward the southern constellation Carina, pulsar and wind nebula (cataloged as IGR J1104-6103) are indicated at the lower right in this remarkable image from the Chandra X-ray Observatory. Energetic particles generated by the pulsar are swept back into the wind's comet-like tail trailing up and to the left, along the direction of the pulsar's motion away from its parent supernova remnant. Both runaway pulsar and...

Explanation: Fading now as it returns to the outer solar system Comet Lovejoy (C/2013 R1) still graces planet Earth's sky, a delicate apparition in binoculars or small telescopes. The comet, a relic of the solar system's formative years, is seen here rising in the morning twilight on January 12 among the stars of Ophiuchus, the Serpent Bearer. Posing near the comet is bright star Alpha Ophiuchi, also known as Rasalhague, from Arabic "the head of the serpent collector". Of course, the serpentine shape below is the ancient Great Wall of China, along the Panlongshan section northeast of Beijing. Panlongshan is...

Explanation: Yes, but how many dark clouds have a multicolored lining? Pictured, behind this darker cloud, is a pileus iridescent cloud, a group of water droplets that have a uniformly similar size and so together diffract different colors of sunlight by different amounts. The above image was taken just before sunset when it was noticed by chance by a photographer in Murambi East, near Odzi Valley and the Mtanda Range of Zimbabwe. Also captured were unusual cloud ripples above the pileus cloud. The formation of a rare pileus cloud capping a common cumulus cloud is an indication that the lower...

Explanation: An important threshold on Mars has now been crossed. Landing in mid-2012, the Curiosity rover is searching for clues of whether life could ever have existed on the red planet. Recent findings of Curiosity include evidence for an ancient (but now dried) freshwater lake, and the non-detection of the biomarker methane in the Martian atmosphere. To continue its investigation, the car-sized rover is on an expedition to roll up Mt. Sharp, the central peak of the large crater in which it landed. Life might have shown preference for water that once ran down the Martian mountain. Two weeks ago,...