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Explanation: Here in the Milky Way galaxy we have astronomical front row seats as M81 and M82 face-off, a mere 12 million light-years away. Locked in a gravitational struggle for the past billion years or so, the two bright galaxies are captured in this deep telescopic snapshot, constructed from 25 hours of image data. Their most recent close encounter likely resulted in the enhanced spiral arms of M81 (left) and violent star forming regions in M82 so energetic the galaxy glows in X-rays. After repeated passes, in a few billion years only one galaxy will remain. From our perspective, this...

Explanation: These three bright nebulae are often featured in telescopic tours of the constellation Sagittarius and the crowded starfields of the central Milky Way. In fact, 18th century cosmic tourist Charles Messier cataloged two of them; M8, the large nebula left of center, and colorful M20 on the right. The third, NGC 6559, is above M8, separated from the larger nebula by a dark dust lane. All three are stellar nurseries about five thousand light-years or so distant. The expansive M8, over a hundred light-years across, is also known as the Lagoon Nebula. M20's popular moniker is the Trifid. Glowing...

Explanation: This beautiful cosmic cloud is a popular stop on telescopic tours of the constellation Sagittarius. Eighteenth century cosmic tourist Charles Messier cataloged the bright nebula as M8. Modern day astronomers recognize the Lagoon Nebula as an active stellar nursery about 5,000 light-years distant, in the direction of the center of our Milky Way Galaxy. Hot stars in the embedded open star cluster NGC 6530 power the nebular glow. Remarkable features can be traced through this sharp picture, showing off the Lagoon's filaments of glowing gas and dark dust clouds. Twisting near the center of the Lagoon, the small, bright...

Explanation: This fifteen degree wide field of view stretches across the crowded starfields of Sagittarius toward the center of our Milky Way galaxy. In fact, the center of the galaxy lies near the right edge of the rich starscape and eleven bright star clusters and nebulae fall near the center of the frame. All eleven are numbered entries in the catalog compiled by 18th century cosmic tourist Charles Messier. Gaining celebrity status with skygazers, M8 (Lagoon), M16 (Eagle), M17 (Omega), and M20 (Trifid) show off the telltale reddish hues of emission nebulae associated with star forming regions. But also eye-catching...

Explanation: Also known as the Cigar Galaxy for its elongated visual appearance, M82 is a starburst galaxy with a superwind. In fact, through ensuing supernova explosions and powerful winds from massive stars, the burst of star formation in M82 is driving a prodigious outflow of material. Evidence for the superwind from the galaxy's central regions is clear in this sharp telescopic snapshot. The composite image highlights emission from long outflow filaments of atomic hydrogen gas in reddish hues. Some of the gas in the superwind, enriched in heavy elements forged in the massive stars, will eventually escape into intergalactic space....

Explanation: Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about two...

Explanation: Sharp telescopic views of magnificent edge-on spiral galaxy NGC 3628 show a puffy galactic disk divided by dark dust lanes. Of course, this deep galactic portrait puts some astronomers in mind of its popular moniker, The Hamburger Galaxy. The tantalizing island universe is about 100,000 light-years across and 35 million light-years away in the northern springtime constellation Leo. NGC 3628 shares its neighborhood in the local Universe with two other large spirals M65 and M66 in a grouping otherwise known as the Leo Triplet. Gravitational interactions with its cosmic neighbors are likely responsible for the extended flare and warp...

Explanation: Beautiful barred spiral galaxy M109, 109th entry in Charles Messier's famous catalog of bright Nebulae and Star Clusters, is found just below the Big Dipper's bowl in the northern constellation Ursa Major. In telescopic views, its striking central bar gives the galaxy the appearance of the Greek letter "theta", θ, a common mathematical symbol representing an angle. Of course M109 spans a very small angle in planet Earth's sky, about 7 arcminutes or 0.12 degrees. But that small angle corresponds to an enormous 120,000 light-year diameter at the galaxy's estimated 60 million light-year distance. The brightest member of the...

Explanation: Sculpted by stellar winds and radiation, the star factory known as Messier 17 lies some 5,500 light-years away in the nebula-rich constellation Sagittarius. At that distance, this degree wide field of view spans almost 100 light-years. The sharp, composite, color image utilizing data from space and ground based telescopes, follows faint details of the region's gas and dust clouds against a backdrop of central Milky Way stars. Stellar winds and energetic light from hot, massive stars formed from M17's stock of cosmic gas and dust have slowly carved away at the remaining interstellar material producing the cavernous appearance and...

Explanation: This beautiful, bright, spiral galaxy is Messier 64, often called the Black Eye Galaxy or the Sleeping Beauty Galaxy for its heavy-lidded appearance in telescopic views. M64 is about 17 million light-years distant in the otherwise well-groomed northern constellation Coma Berenices. In fact, the Red Eye Galaxy might also be an appropriate moniker in this colorful composition of narrow and wideband images. The enormous dust clouds obscuring the near-side of M64's central region are laced with the telltale reddish glow of hydrogen associated with star forming regions. But they are not this galaxy's only peculiar feature. Observations show that...

Explanation: The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51, also known as NGC 5194, is one of the brightest and most picturesque galaxies on the sky. The above image is a digital combination of a ground-based image from the 0.9-meter telescope at Kitt Peak National Observatory and a space-based image from the Hubble Space Telescope highlighting sharp features normally too red to be seen. Anyone with a good pair of binoculars, however, can see this Whirlpool toward the constellation of the Hunting Dogs (Canes Venatici....

Explanation: Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax galaxy cluster. This sharp color image shows intense star forming regions at the ends of the bar and along the spiral arms, and details of dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming...

Explanation: M7 is one of the most prominent open clusters of stars on the sky. The cluster, dominated by bright blue stars, can be seen with the naked eye in a dark sky in the tail of the constellation of the Scorpion (Scorpius). M7 contains about 100 stars in total, is about 200 million years old, spans 25 light-years across, and lies about 1000 light-years away. The above deep exposure was taken from Hakos Farm in Namibia. The M7 star cluster has been known since ancient times, being noted by Ptolemy in the year 130 AD. Also visible are a...

Explanation: Follow the handle of the Big Dipper away from the dipper's bowl until you get to the handle's last bright star. Then, just slide your telescope a little south and west and you might find this stunning pair of interacting galaxies, the 51st entry in Charles Messier famous catalog. Perhaps the original spiral nebula, the large galaxy with well defined spiral structure is also cataloged as NGC 5194. Its spiral arms and dust lanes clearly sweep in front of its companion galaxy (top), NGC 5195. The pair are about 31 million light-years distant and officially lie within the angular...

Explanation: Close to the Great Bear (Ursa Major) and surrounded by the stars of the Hunting Dogs (Canes Venatici), this celestial wonder was discovered in 1781 by the metric French astronomer Pierre Mechain. Later, it was added to the catalog of his friend and colleague Charles Messier as M106. Modern deep telescopic views reveal it to be an island universe: a spiral galaxy around 30 thousand light-years across located only about 21 million light-years beyond the stars of the Milky Way. Along with prominent dust lanes and a bright central core, this colorful composite image highlights youthful blue star clusters...

Explanation: Recorded on August 2, this telescopic composite image catches Comet Garradd (C/2009 P1) in the same field of view as globular star cluster M15. The celestial scene would have been a rewarding one for influential 18th century comet hunter Charles Messier. While Messier scanned French skies for comets, he carefully cataloged positions of things which might be fuzzy and comet-like in appearance but did not move against the background stars and so were definitely not comets. M15 (lower right), the 15th entry in his famous not-a-comet catalog, is now understood to be a cluster of over 100,000 stars some...

[Image Credit & Copyright: Babak Tafreshi (TWAN)] Explanation: In this action scene, red night vision lights, green laser pointers, tripods and telescopes in faint silhouette surround intrepid sky gazers embarked on the 10th annual Iran Messier Marathon. Completing the marathon requires viewing all 110 objects in 18th century French astronomer Charles Messier's catalog in one glorious dusk-to-dawn observing run. As daunting as it sounds, there are often favorable weekend dates for northern hemisphere marathoners to complete the task that fall on nearly moonless nights near the spring equinox. With the Milky Way as a backdrop, this group of about 150...