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Saturn, Tethys, Rings, and Shadows

Seen from ice moon Tethys, rings and shadows would display fantastic views of the Saturnian system. Haven’t dropped in on Tethys lately? Then this gorgeous ringscape from the Cassini spacecraft will have to do for now. Caught in sunlight just below and left of picture center in 2005, Tethys itself is about 1,000 kilometers in diameter and orbits not quite five saturn-radii from the center of the gas giant planet. At that distance (around 300,000 kilometers) it is well outside Saturn’s main bright rings, but Tethys is still one of five major moons that find themselves within the boundaries of the faint and tenuous outer E ring. Discovered in the 1980s, two very small moons Telesto and Calypso are locked in stable along Tethys’ orbit. Telesto precedes and Calypso follows Tethys as the trio circles Saturn. via NASA

The Full Moon and the Dancer

On Monday, January’s Full Moon rose as the Sun set. Spotted near the eastern horizon, its warm hues are seen in this photo taken near Cagliari, capital city of the Italian island of Sardinia. Of course the familiar patterns of light and dark across the Moon’s nearside are created by bright rugged highlands and dark smooth lunar maria. Traditionally the patterns are seen as pareidolia, giving the visual illusion of a human face like the Man in the Moon, or familiar animal like the Moon rabbit. But for a moment the swarming murmuration, also known as a flock of starlings, frozen in the snapshot’s field of view lends another pareidolic element to the scene. Some see the graceful figure of a dancer enchanted by moonlight. via NASA

Young Star Jet MHO 2147

Laser guide stars and adaptive optics sharpened this stunning ground-based image of stellar jets from the Gemini South Observatory, Chilean Andes, planet Earth. These twin outflows of MHO 2147 are from a young star in formation. It lies toward the central Milky Way and the boundary of the constellations Sagittarius and Ophiuchus at an estimated distance of some 10,000 light-years. At center, the star itself is obscured by a dense region of cold dust. But the infrared image still traces the sinuous jets across a frame that would span about 5 light-years at the system’s estimated distance. Driven outward by the young rotating star, the apparent wandering direction of the jets is likely due to precession. Part of a multiple star system, the young star’s rotational axis would slowly precess or wobble like a top under the gravitation influence of its nearby companions. via NASA

NGC 7822 in Cepheus

Hot, young stars and cosmic pillars of gas and dust seem to crowd into NGC 7822. At the edge of a giant molecular cloud toward the northern constellation Cepheus, the glowing star forming region lies about 3,000 light-years away. Within the nebula, bright edges and dark shapes stand out in this colorful telescopic skyscape. The image includes data from narrowband filters, mapping emission from atomic oxygen, hydrogen, and sulfur into blue, green, and red hues. The emission line and color combination has become well-known as the Hubble palette. The atomic emission is powered by energetic radiation from the central hot stars. Their powerful winds and radiation sculpt and erode the denser pillar shapes and clear out a characteristic cavity light-years across the center of the natal cloud. Stars could still be forming inside the pillars by gravitational collapse but as the pillars are eroded away, any forming stars will ultimately be cutoff from their reservoir of star stuff. This field of view spans about 40 light-years at the estimated distance of NGC 7822. via NASA

M31: The Andromeda Galaxy

The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy. Even at some two and a half million light-years distant, this immense spiral galaxy — spanning over 200,000 light years — is visible, although as a faint, nebulous cloud in the constellation Andromeda. In contrast, a bright yellow nucleus, dark winding dust lanes, and expansive spiral arms dotted with blue star clusters and red nebulae, are recorded in this stunning telescopic image which combines data from orbiting Hubble with ground-based images from Subaru and Mayall. In only about 5 billion years, the Andromeda galaxy may be even easier to see — as it will likely span the entire night sky — just before it merges with our Milky Way Galaxy. via NASA

From Orion to the Southern Cross

This is a sky filled with glowing icons. On the far left is the familiar constellation of Orion, divided by its iconic three-aligned belt stars and featuring the famous Orion Nebula, both partly encircled by Barnard’s Loop. Just left of center in the featured image is the brightest star in the night: Sirius. Arching across the image center is the central band of our Milky Way Galaxy. On the far right, near the top, are the two brightest satellite galaxies of the Milky Way: the Large Magellanic Cloud (LMC), and the Small Magellanic Cloud (SMC). Also on the far right — just above the cloudy horizon — is the constellation of Crux, complete with the four stars that make the iconic Southern Cross. The featured image is a composite of 18 consecutive exposures taken by the same camera and from the same location in eastern Australia during the last days of last year. In the foreground, picturesque basalt columns of the Bombo Quarry part to reveal the vast Pacific Ocean. via NASA

Chamaeleon Dark Nebulas

Sometimes the dark dust of interstellar space has an angular elegance. Such is the case toward the far-south constellation of Chamaeleon. Normally too faint to see, dark dust is best known for blocking visible light from stars and galaxies behind it. In this four-hour exposure, however, the dust is seen mostly in light of its own, with its strong red and near-infrared colors giving creating a brown hue. Contrastingly blue, the bright star Beta Chamaeleontis is visible just to the right of center, with the dust that surrounds it preferentially reflecting blue light from its primarily blue-white color. All of the pictured stars and dust occur in our own Milky Way Galaxy with — but one notable exception: the white spot just below Beta Chamaeleontis is the galaxy IC 3104 which lies far in the distance. Interstellar dust is mostly created in the cool atmospheres of giant stars and dispersed into space by stellar light, stellar winds, and stellar explosions such as supernovas. via NASA

A Retreating Thunderstorm at Sunset

What type of cloud is that? This retreating cumulonimbus cloud, more commonly called a thundercloud, is somewhat unusual as it contains the unusual bumpiness of a mammatus cloud on the near end, while simultaneously producing falling rain on the far end. Taken in mid-2013 in southern Alberta, Canada, the cloud is moving to the east, into the distance, as the sun sets in the west, behind the camera. In the featured image, graphic sunset colors cross the sky to give the already photogenic cloud striking orange and pink hues. A darkening blue sky covers the background. Further in the distance, a rising, waxing, gibbous moon is visible on the far right. via NASA

Galileo’s Europa

Looping through the Jovian system in the late 1990s, the Galileo spacecraft recorded stunning views of Europa and uncovered evidence that the moon’s icy surface likely hides a deep, global ocean. Galileo’s Europa image data has been remastered here, with improved calibrations to produce a color image approximating what the human eye might see. Europa’s long curving fractures hint at the subsurface liquid water. The tidal flexing the large moon experiences in its elliptical orbit around Jupiter supplies the energy to keep the ocean liquid. But more tantalizing is the possibility that even in the absence of sunlight that process could also supply the energy to support life, making Europa one of the best places to look for life beyond Earth. What kind of life could thrive in a deep, dark, subsurface ocean? Consider planet Earth’s own extreme shrimp. via NASA

NGC 1566: The Spanish Dancer Spiral Galaxy

An island universe of billions of stars, NGC 1566 lies about 60 million light-years away in the southern constellation Dorado. Popularly known as the Spanish Dancer galaxy, it’s seen face-on from our Milky Way perspective. A gorgeous grand design spiral, this galaxy’s two graceful spiral arms span over 100,000 light-years, traced by bright blue star clusters, pinkish starforming regions, and swirling cosmic dust lanes. NGC 1566’s flaring center makes the spiral one of the closest and brightest Seyfert galaxies. It likely houses a central supermassive black hole wreaking havoc on surrounding stars, gas, and dust. In this sharp southern galaxy portrait, the spiky stars lie well within the Milky Way. via NASA