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Companion of a Young, Sun-like Star Confirmed Credit: Gemini Observatory, D. Lafreniere, R. Jayawardhana, M. van Kerkwijk (Univ. Toronto) Explanation: The first direct image of an extrasolar planet orbiting a star similar to our Sun has been confirmed. Located just 500 light-years away toward the constellation Scorpius, the parent star, cataloged as 1RXS J160929.1-210524, is only slightly less massive and a little cooler than the Sun. The star is, however, much younger, a few million years old compared to the middle-aged Sun's 5 billion years. This sharp infrared image shows the young star's planetary companion positioned above and left...

A Giant Planet for Beta Pic Credit: A.-M. Lagrange, D. Ehrenreich (LAOG), et al., ESO Explanation: A mere 50 light-years away, young star Beta Pictoris became one of the most important stars in the sky in the early 1980s. Satellite and ground-based telescopic observations revealed the presence of a surrounding outer, dusty, debris disk and an inner clear zone about the size of our solar system -- strong evidence for the formation of planets. Infrared observations from European Southern Observatory telescopes subsequently detected a source in the clear zone, now confirmed as a giant planet orbiting Beta Pic. The...

Galaxies on a String Image Credit & Copyright: Adam Block, Mt. Lemmon SkyCenter, U. Arizona Explanation: Galaxies NGC 5216 (top) and NGC 5218 really do look like they are connected by a string. Of course, that string is a cosmic trail of gas, dust, and stars about 22,000 light-years long. Also known as Keenan's system (for its discoverer) and Arp 104, the interacting galaxy pair is some 17 million light-years away in the constellation Ursa Major. The debris trail that joins them, along with NGC 5218's comma-shaped extension and the distorted arms of NGC 5216, are a consequence of...

Above Aurora Australis Credit: ISS Expedition 23 Crew, ISAL, NASA Explanation: On May 29, looking southward from a vantage point about 350 kilometers above the southern Indian Ocean, astronauts onboard the International Space Station watched this enormous, green ribbon shimmering below. Known as aurora australis or southern lights, the shifting, luminous bands are commonly seen at high northern latitudes as well, there known as the aurora borealis or northern lights. North or south their cause is the same though, as energetic charged particles from the magnetosphere pile into the atmosphere near the Earth's poles. To produce the characteristic greenish...

Fast Gas Bullet from Cosmic Blast N49 Credit: X-ray: NASA/CXC/Penn State/S. Park et al.; Optical: NASA/STScI/UIUC/Y. H. Chu & R. Williams et al. Explanation: What is that strange blue blob on the far right? No one is sure, but it might be a speeding remnant of a powerful supernova that was unexpectedly lopsided. Scattered debris from supernova explosion N49 lights up the sky in this gorgeous composited image based on data from the Chandra and Hubble Space Telescopes. Glowing visible filaments, shown in yellow, and X-ray hot gas, shown in blue, span about 30 light-years in our neighboring galaxy,...

A Partial Lunar Eclipse Credit & Copyright: Brad Riza Explanation: What's happened to the Moon? This past weekend, once again, part of the Moon moved through the Earth's shadow. This happens about once or twice a year, on the average, but not each month since the Moon's orbit around the Earth is slightly tilted. Pictured above, the face of a full moon is partly blocked by Earth's clouds, and partly darkened on the upper right by Earth's umbral shadow. Clouds permitting, the partial lunar eclipse was visible from the half of the Earth facing the Moon at the time...

All the Colors of the Sun Credit & Copyright:Nigel Sharp (NSF), FTS, NSO, KPNO, AURA, NSF Explanation: It is still not known why the Sun's light is missing some colors. Shown above are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device. The above spectrum was created at the McMath-Pierce Solar Observatory and shows, first off, that although our yellow-appearing Sun emits light of nearly every color, it does indeed appear brightest in yellow-green light. The dark patches in the above spectrum arise from gas at or above the Sun's surface...

The Starry Night of Alamut Image Credit & Copyright: Babak Tafreshi (TWAN) Explanation: A meteor's streak and the arc of the Milky Way hang over the imposing mountain fortress of Alamut in this starry scene. Found in the central Alborz Mountains of Iran, Alamut Castle was built into the rock in the 9th century. The name means Eagle's Nest. Home of the legendary Assassins featured in the adventure movie Prince of Persia, Alamut was also historically a center for libraries and education. For a time, it was the residence of important 13th century Persian scholar and astronomer Nasir al-Din...

The Dark Tower in Scorpius Image Credit & Copyright: Thomas V. Davis (tvdavisastropix.com) Explanation: In silhouette against a crowded star field toward the constellation Scorpius, this dusty cosmic cloud evokes for some the image of an ominous dark tower. In fact, clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across the gorgeous telescopic view. Known as a cometary globule, the swept-back cloud, extending from the lower left to the head (top of the tower) right and above center, is shaped by intense ultraviolet...

Sunset from the International Space Station Credit: Expedition 23 Crew, NASA Explanation: What are these strange color bands being seen from the International Space Station? The Sun setting through Earth's atmosphere. Pictured above, a sunset captured last month by the ISS's Expedition 23 crew shows in vivid detail many layers of the Earth's thin atmosphere. Part of the Earth experiencing night crosses the bottom of the image. Above that, appearing in deep orange and yellow, is the Earth's troposphere, which contains 80 percent of the atmosphere by mass and almost all of the clouds in the sky. Visible as...

Sunrise Solstice at Stonehenge Credit & Copyright: Max Alexander, STFC, SPL Explanation: Today the Sun reaches its northernmost point in planet Earth's sky. Called a solstice, the date traditionally marks a change of seasons -- from spring to summer in Earth's Northern Hemisphere and from fall to winter in Earth's Southern Hemisphere. The above image was taken during the week of the 2008 summer solstice at Stonehenge in United Kingdom, and captures a picturesque sunrise involving fog, trees, clouds, stones placed about 4,500 years ago, and a 5 billion year old large glowing orb. Even given the precession of...

Abell 2218: A Galaxy Cluster Lens Credit: Andrew Fruchter (STScI) et al., WFPC2, HST, NASA Digitally reprocessed: Al Kelly Explanation: What are those strange filaments? Background galaxies. Gravity can bend light, allowing huge clusters of galaxies to act as telescopes, and distorting images of background galaxies into elongated strands. Almost all of the bright objects in this Hubble Space Telescope image are galaxies in the cluster known as Abell 2218. The cluster is so massive and so compact that its gravity bends and focuses the light from galaxies that lie behind it. As a result, multiple images of these...

Comet McNaught Passes NGC 1245 Image Credit & Copyright: Rich Richins Explanation: Of the many comets named for discoverer Robert McNaught, the one cataloged as C/2009 R1 is gracing dawn skies for northern hemisphere observers this month. Seen here on June 13th from southern New Mexico, this Comet McNaught's long ion tail sweeps across the telescopic field of view (a negative image is inset). Remarkably, the ion tail easily stretches past background star cluster NGC 1245 (upper left) in the constellation Perseus, about 1.5 degrees from the comet's lovely greenish head or coma. The coma also sports a short,...

The Red Rectangle Nebula from Hubble Credit: ESA, Hubble, NASA Explanation: How was the unusual Red Rectangle nebula created? At the nebula's center is a young binary star system that surely powers the nebula but does not, as yet, explain its colors. The unusual shape of the Red Rectangle is likely due to a thick dust torus which pinches the otherwise spherical outflow into tip-touching cone shapes. Because we view the torus edge-on, the boundary edges of the cone shapes seem to form an X. The distinct rungs suggest the outflow occurs in fits and starts. The unusual colors...

Retrograde Mars Credit & Copyright: Tunç Tezel (TWAN) Explanation: Why would Mars appear to move backwards? Most of the time, the apparent motion of Mars in Earth's sky is in one direction, slow but steady in front of the far distant stars. About every two years, however, the Earth passes Mars as they orbit around the Sun. During the most recent such pass late last year and early this year, Mars as usual, loomed large and bright. Also during this time, Mars appeared to move backwards in the sky, a phenomenon called retrograde motion. Pictured above is a series...

The Medusa Nebula Image Credit & Copyright: Bob Franke (Focal Pointe Observatory) Explanation: Braided, serpentine filaments of glowing gas suggest this nebula's popular name, The Medusa Nebula. Also known as Abell 21, this Medusa is an old planetary nebula some 1,500 light-years away in the constellation Gemini. Like its mythological namesake, the nebula is associated with a dramatic transformation. The planetary nebula phase represents a final stage in the evolution of low mass stars like the sun, as they transform themselves from red giants to hot white dwarf stars and in the process shrug off their outer layers. Ultraviolet...

Hydrogen in M51 Credit & Copyright: CAHA, Descubre Foundation, DSA, OAUV, Vicent Peris (OAUV / PixInsight), Jack Harvey (SSRO), Steven Mazlin (SSRO), Carlos Sonnenstein (Valkanik), Juan Conejero (PixInsight). Explanation: Perhaps the original spiral nebula, M51 is a large galaxy, over 60,000 light-years across, with a readily apparent spiral structure. Also cataloged as NGC 5194, M51 is a part of a well-known interacting galaxy pair, its spiral arms and dust lanes clearly sweeping in front of companion galaxy NGC 5195 (top). This dramatically processed color composite combines M51 image data from the Calar Alto Observatory's 1.2 meter telescope. The data...

Regulus and the Red Planet Image Credit & Copyright: Babak Tafreshi (TWAN) Explanation: Leo's royal star Regulus and red planet Mars appear in a colorful pairing just above the horizon in this starry skyscape. The photo was taken on June 4th from Oraman, a mountainous region of Kurdistan in western Iran near the border with Iraq. The marked color contrast between Mars and the bright blue star was easy to discern by eye, but is further enhanced in the picture through the use of a diffusion filter. Otherwise dominating the western evening sky, brilliant Venus has already set below...

Orange Sun Simmering Credit & Copyright: Alan Friedman (Averted Imagination) Explanation: Even a quiet Sun can be a busy place. And over the deep Solar Minimum of the past few years, our Sun has been unusually quiet. The above image, taken last week in a single color of light called Hydrogen Alpha and then false colored, records a great amount of detail of the simmering surface of our parent star. The gradual brightening towards the Sun's edge in this color-inverted image, called limb darkening, is caused by increased absorption of relatively cool solar gas. Just over the Sun's edges,...

Comet McNaught Becoming Visible to the Unaided Eye Credit & Copyright: Jose Francisco Hernandez (Altamira Observartory) Explanation: A new comet is brightening and is now expected to become visible to the unaided eye later this month. C/2009 R1 (McNaught) is already showing an impressive tail and is currently visible through binoculars. The above image, taken yesterday from the Altamira Observatory in the Canary Islands and spanning about five degrees, shows an impressive green coma and a long ion tail in front of distant star trails. Although predicting the brightness of comets is notoriously difficult, current estimates place Comet McNaught...