What's happening at the center of spiral galaxy M83? Just about everything, from the looks of it. M83 is one of the closest spiral galaxies to our own Milky Way Galaxy and from a distance of 15 million light-years , appears to be relatively normal. Zooming in on M83 's nucleus with the latest telescopes, however, shows the center to be an energetic and busy place. Visible in the above image -- from the newly installed Wide Field Camera 3 pointing through the recently refurbished Hubble Space Telescope -- are bright newly formed stars and giant lanes of dark dust . An image with similar perspective from the Chandra X-ray Observatory shows the region is also rich in very hot gas and small bright sources. The remnants of about 60 supernova blast s can be found in the above image .

It looks like a ring on the sky. Hundreds of years ago astronomers noticed a nebula with a most unusual shape. Now known as M57 or NGC 6720, the gas cloud became popularly known as the Ring Nebula . It is now known to be a planetary nebula , a gas cloud emitted at the end of a Sun-like star's existence. As one of the brightest planetary nebula on the sky, the Ring Nebula can be seen with a small telescope in the constellation of Lyra . The Ring Nebula lies about 4,000 light years away, and is roughly 500 times the diameter of our Solar System . In this picture by the Hubble Space Telescope in 1998, dust filaments and globules are visible far from the central star. This helps indicate that the Ring Nebula is not spherical, but cylindrical .

What's 93 million miles away and still hurts your eyes when you look at it? The answer is not the Denver International Airport, known to some travelers as DIA. But DIA does appear in dramatic silhouette in the foreground of this telephoto image. The view looks east toward the airport terminal's characteristic multi-peaked roof and the rising October Sun. The roof's appearance suggests the snow-capped peaks of the region's Rocky Mountains to the west. As winter approaches for denizens of Denver and the northern hemisphere in general, the rising Sun will continue to move south (image right) in the coming days. Of course, the Sun is 93 million miles away ...

Cosmic dust clouds and embedded newborn stars glow at infrared wavelengths in this tantalizing false-color view from the Spitzer Space Telescope. Pictured is of one of the closest star forming regions, part of the Rho Ophiuchi cloud complex some 400 light-years distant near the southern edge of the pronounceable constellation Ophiuchus . The view spans about 5 light-years at that estimated distance. After forming along a large cloud of cold molecular hydrogen gas, newborn stars heat the surrounding dust to produce the infrared glow. An exploration of the region in penetrating infrared light has detected some 300 emerging and newly formed stars whose average age is estimated to be a mere 300,000 years -- extremely young compared to the Sun's age of 5 billion years.

This beautiful telescopic skyscape features spiral galaxy NGC 981. The island universe is about 50,000 light-years across and lies some 60 million light-years away toward the constellation Aries . An artistic presentation , the image shows spiky foreground stars in our own Milky Way Galaxy and convoluted dust clouds that hang above our galactic plane, dimly reflecting starlight. It also captures NGC 981 in a cosmic moment important to astrophysicists on planet Earth. Light from supernova SN2009js, absent in previous images, is indicated by the two lines just below and left of the galaxy's center. The supernova itself is the death explosion of a massive star within the plane of galaxy NGC 981 . It was just discovered in October by supernova search teams in Japan and the US.

Where can a telescope take you? Four hundred years ago, a telescope took Galileo to the Moon to discover craters, to Saturn to discover rings, to Jupiter to discover moons, to Venus to discover phases, and to the Sun to discover spots. Today, in celebration of Galileo's telescopic achievements and as part of the International Year of Astronomy , NASA has used its entire fleet of Great Observatories , and the Internet , to bring the center of our Galaxy to you. Pictured above , in greater detail and in more colors than ever seen before, are the combined images of the Hubble Space Telescope in optical light, the Spitzer Space Telescope in infrared light, and the Chandra X-ray Observatory in X-ray light. A menagerie of vast stars fields are visible , along with dense star clusters, long filaments of gas and dust, expanding supernova remnants, and the energetic surroundings of what likely is our Galaxy's central black hole. Many of these features are labeled on a complementary annotated image . Of course, a telescope 's magnification and light gathering ability creates only an image of what a human could see if visiting these places. To actually go requires rockets .

The other side of Saturn's ring plane is now directly illuminated by the Sun. For the previous 15 years, the southern side of Saturn and its rings were directly illuminated, but since Saturn's equinox in August, the orientation has reversed. Pictured above last month, the robotic Cassini spacecraft orbiting Saturn has captured the giant planet and its majestic rings soon after equinox. Imaged from nearly behind, Saturn and its moon Tethys each show a crescent phase to Cassini that is not visible from Earth. As the rings continue to point nearly toward the Sun, only a thin shadow of Saturn's rings is visible across the center of the planet. Close inspection of Saturn's rings, however, shows superposed bright features identified as spokes that are thought to be groups of very small electrically charged ice particles. Understanding the nature and dynamics of spokes is not fully understood and remains a topic of research .

Where do stars form when galaxies collide? To help find out, astronomers imaged the nearby galaxy merger NGC 2623 in high resolution with the Hubble Space Telescope in 2007. Analysis of this Hubble image and images of NGC 2623 in infrared light by the Spitzer Space Telescope , in X-ray light by XMM-Newton , and in ultraviolet light by GALEX , indicate that two originally spiral galaxies appear now to be greatly convolved and that their cores have unified into one active galactic nucleus (AGN). Star formation continues around this core near the above image center, along the stretched out tidal tail s visible on either side, and perhaps surprisingly, in an off-nuclear region on the upper left where clusters of bright blue stars appear. Galaxy collisions can take hundreds of millions of years and take several gravitationally destructive passes. NGC 2623 , also known as Arp 243, spans about 50,000 light years and lies about 250 million light years away toward the constellation of the Crab (Cancer) . Reconstructing the original galaxies and how galaxy mergers happen is often challenging, sometimes impossible, but generally important to understanding how our universe evolved .

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 last month over several nights from Yalbraith, NSW , Australia . The M7 star cluster has been known since ancient times, being noted by Ptolemy in the year 130 AD . Also visible are a dark dust cloud and literally millions of unrelated stars towards the Galactic center .

Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall. Asaph Hall discovered both the Red Planet's moons in 1877. Over 9 kilometers across, Stickney is nearly half the diameter of Phobos itself , so large that the impact that blasted out the crater likely came close to shattering the tiny moon. This stunning, enhanced-color image of Stickney and surroundings was recorded by the HiRISE camera onboard the Mars Reconnaissance Orbiter as it passed within some six thousand kilometers of Phobos in March of 2008. Even though the surface gravity of asteroid-like Phobos is less than 1/1000th Earth's gravity, streaks suggest loose material has slid down inside the crater walls over time. Light bluish regions near the crater's rim could indicate a relatively freshly exposed surface. The origin of the curious grooves along the surface is mysterious but may be related to the crater-forming impact.