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Explanation: A jewel of the southern sky, the Great Carina Nebula, also known as NGC 3372, spans over 300 light-years, one of our galaxy's largest star forming regions. Like the smaller, more northerly Great Orion Nebula, the Carina Nebula is easily visible to the unaided eye, though at a distance of 7,500 light-years it is some 5 times farther away. This gorgeous telescopic close-up reveals remarkable details of the region's central glowing filaments of interstellar gas and obscuring cosmic dust clouds. The field of view is over 50 light-years across. The Carina Nebula is home to young, extremely massive stars,...

Explanation: The prominent ridge of emission featured in this sharp, colorful skyscape is cataloged as IC 5067. Part of a larger emission nebula with a distinctive shape, popularly called The Pelican Nebula, the ridge spans about 10 light-years following the curve of the cosmic pelican's head and neck. This false-color view also translates the pervasive glow of narrow emission lines from atoms in the nebula to a color palette made popular in Hubble Space Telescope images of star forming regions. Fantastic, dark shapes inhabiting the 1/2 degree wide field are clouds of cool gas and dust sculpted by the winds...

Explanation: What created this great arc in space? This arcing, graceful structure is actually a bow shock about half a light-year across, created as the wind from young star LL Orionis collides with the Orion Nebula flow. Adrift in Orion's stellar nursery and still in its formative years, variable star LL Orionis produces a wind more energetic than the wind from our own middle-aged sun. As the fast stellar wind runs into slow moving gas a shock front is formed, analogous to the bow wave of a boat moving through water or a plane traveling at supersonic speed. The slower...

Explanation: The Great Nebula in Orion is a colorful place. Visible to the unaided eye, it appears as a small fuzzy patch in the constellation of Orion. Long exposure, multi-wavelength images like this, however, show the Orion Nebula to be a busy neighborhood of young stars, hot gas, and dark dust. This digital composite features not only three colors of visible light but four colors of infrared light taken by NASA's orbiting Spitzer Space Telescope as well. The power behind much of the Orion Nebula (M42) is the Trapezium - four of the brightest stars in the nebula. Many of...

Explanation: What forms lurk in the mists of the Carina Nebula? The dark ominous figures are actually molecular clouds, knots of molecular gas and dust so thick they have become opaque. In comparison, however, these clouds are typically much less dense than Earth's atmosphere. Featured here is a detailed image of the core of the Carina Nebula, a part where both dark and colorful clouds of gas and dust are particularly prominent. The image was captured last month from Siding Spring Observatory in Australia. Although the nebula is predominantly composed of hydrogen gas -- here colored green, the image was...

Explanation: Planets, stars, nebulas and a galaxy -- this impressive image has them all. Closest to home are the two planets Mars (right) and Saturn (center), visible as the two bright orange spots in the upper half of the featured image. On the central right are the colorful Rho Ophiuchus star clouds featuring the bright orange star Antares lined up below Mars. These interstellar clouds contain both red emission nebulas and blue reflection nebulas. At the top right of the image is the Blue Horsehead reflection nebula. On the lower left are many dark absorption nebulas that extend from the...

Explanation: These cosmic clouds have blossomed 1,300 light-years away, in the fertile starfields of the constellation Cepheus. Called the Iris Nebula, NGC 7023 is not the only nebula to evoke the imagery of flowers, though. Still, this deep telescopic image shows off the Iris Nebula's range of colors and symmetries, embedded in surrounding fields of interstellar dust. Within the Iris itself, dusty nebular material surrounds a hot, young star. The dominant color of the brighter reflection nebula is blue, characteristic of dust grains reflecting starlight. Central filaments of the reflection nebula glow with a faint reddish photoluminesence as some dust...

Explanation: It's easy to get lost following the intricate strands of the Spaghetti Nebula. A supernova remnant cataloged as Simeis 147 and Sh2-240, the glowing gas filaments cover nearly 3 degrees -- 6 full moons -- on the sky. That's about 150 light-years at the stellar debris cloud's estimated distance of 3,000 light-years. This sharp composite includes image data taken through a narrow-band filter to highlight emission from hydrogen atoms tracing the shocked, glowing gas. The supernova remnant has an estimated age of about 40,000 years, meaning light from the massive stellar explosion first reached Earth about 40,000 years ago....

The Bubble Nebula, also known as NGC 7653, is an emission nebula located 11,000 light-years away. This stunning new image was observed by the NASA/ESA Hubble Space Telescope to celebrate its 26th year in space. Credit: NASA, ESA, Hubble Heritage Team =============================================================================================================== This new NASA/ESA Hubble Space Telescope image, released to celebrate Hubble's 26th year in orbit, captures in stunning clarity what looks like a gigantic cosmic soap bubble. The object, known as the Bubble Nebula, is in fact a cloud of gas and dust illuminated by the brilliant star within it. The vivid new portrait of this dramatic scene...

Explanation: Now sweeping high above the ecliptic plane, Comet Lemmon has faded dramatically in planet Earth's night sky as it heads for the outer solar system. Some 16 light-minutes (2 AU) from the Sun, it still sports a greenish coma though, posing on the right in this 4 degree wide telescopic view from last Saturday with deep sky star clusters and nebulae in Cassiopeia. In fact, the rich background skyscape is typical within the boundaries of the boastful northern constellation that lie along the crowded starfields of the Milky Way. Included near center is open star cluster M52 about 5,000...

Explanation: Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 10 light-year diameter bubble offers evidence of violent processes at work. Above and right of the Bubble's center is a hot, O star, several hundred thousand times more luminous and around 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The...

Explanation: It's the bubble versus the cloud. NGC 7635, the Bubble Nebula, is being pushed out by the stellar wind of massive central star BD+602522. Next door, though, lives a giant molecular cloud, visible to the right. At this place in space, an irresistible force meets an immovable object in an interesting way. The cloud is able to contain the expansion of the bubble gas, but gets blasted by the hot radiation from the bubble's central star. The radiation heats up dense regions of the molecular cloud causing it to glow. The Bubble Nebula, pictured above in scientifically mapped colors...

Explanation: Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 7 light-year diameter bubble offers evidence of violent processes at work. Above and left of the Bubble's center is a hot, O-type star, several hundred thousand times more luminous and around 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The...

Explanation: It's the bubble versus the cloud. NGC 7635, the Bubble Nebula, is being pushed out by the stellar wind of massive central star BD+602522. Next door, though, lives a giant molecular cloud, visible to the right. At this place in space, an irresistible force meets an immovable object in an interesting way. The cloud is able to contain the expansion of the bubble gas, but gets blasted by the hot radiation from the bubble's central star. The radiation heats up dense regions of the molecular cloud causing it to glow. The Bubble Nebula, featured here in scientifically mapped colors...

Explanation: In one of the brightest parts of Milky Way lies a nebula where some of the oddest things occur. NGC 3372, known as the Great Nebula in Carina, is home to massive stars and changing nebulas. The Keyhole Nebula (NGC 3324), the bright structure just above the image center, houses several of these massive stars and has itself changed its appearance. The entire Carina Nebula spans over 300 light years and lies about 7,500 light-years away in the constellation of Carina. Eta Carinae, the most energetic star in the nebula, was one of the brightest stars in the sky...

Explanation: Sometimes even the dark dust of interstellar space has a serene beauty. One such place occurs toward the constellation of Taurus. The filaments featured here can be found on the sky between the Pleiades star cluster and the California Nebula. This dust is not known not for its bright glow but for its absorption and opaqueness. Several bright stars are visible with their blue light seen reflecting off the brown dust. Other stars appear unusually red as their light barely peaks through a column of dark dust, with red the color that remains after the blue is scattered away....

Explanation: Massive star IRS 4 is beginning to spread its wings. Born only about 100,000 years ago, material streaming out from this newborn star has formed the nebula dubbed Sharpless 2-106 Nebula (S106), featured here. A large disk of dust and gas orbiting Infrared Source 4 (IRS 4), visible in brown near the image center, gives the nebula an hourglass or butterfly shape. S106 gas near IRS 4 acts as an emission nebula as it emits light after being ionized, while dust far from IRS 4 reflects light from the central star and so acts as a reflection nebula. Detailed...

Explanation: What could cause a nebula to appear square? No one is quite sure. The hot star system known as MWC 922, however, appears to be embedded in a nebula with just such a shape. The featured image combines infrared exposures from the Hale Telescope on Mt. Palomar in California, and the Keck-2 Telescope on Mauna Kea in Hawaii. A leading progenitor hypothesis for the square nebula is that the central star or stars somehow expelled cones of gas during a late developmental stage. For MWC 922, these cones happen to incorporate nearly right angles and be visible from the...

Explanation: Cosmic dust clouds ripple across this infrared portrait of our Milky Way's satellite galaxy, the Large Magellanic Cloud. In fact, the remarkable composite image from the Herschel Space Observatory and the Spitzer Space Telescope show that dust clouds fill this neighboring dwarf galaxy, much like dust along the plane of the Milky Way itself. The dust temperatures tend to trace star forming activity. Spitzer data in blue hues indicate warm dust heated by young stars. Herschel's instruments contributed the image data shown in red and green, revealing dust emission from cooler and intermediate regions where star formation is just...

Explanation: The 1970s are sometimes ignored by astronomers, like this beautiful grouping of reflection nebulae in Orion - NGC 1977, NGC 1975, and NGC 1973 - usually overlooked in favor of the substantial glow from the nearby stellar nursery better known as the Orion Nebula. Found along Orion's sword just north of the bright Orion Nebula complex, these reflection nebulae are also associated with Orion's giant molecular cloud about 1,500 light-years away, but are dominated by the characteristic blue color of interstellar dust reflecting light from hot young stars. In this sharp color image a portion of the Orion Nebula...