What are those colorful rings around the Moon? A corona. Rings like this will sometimes appear when the Moon is seen through thin clouds. The effect is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud. Since light of different colors has different wavelengths, each color diffracts differently. Lunar Coronae are one of the few quantum mechanical color effects that can be easily seen with the unaided eye. The featured lunar corona was captured around a Strawberry Moon on June 2 from La Plata, Argentina. Similar coronae that form around the Sun are typically harder to see because of the Sun’s great brightness.

from NASA http://ift.tt/1IF9Pt1
via IFTTT

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 along the southern border of 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 radiation from the hot star powers the nebular glow. An unrelated, bright, foreground star is near center in this close-up, telescopic view, while the Medusa’s transforming central star is actually the dimmer star below center and toward the right-hand part of the frame. The Medusa Nebula is estimated to be over 4 light-years across.

from NASA http://ift.tt/1S9BC9h
via IFTTT

This colorful skyscape spans about three full moons (1.5 degrees) across nebula rich starfields along the plane of our Milky Way Galaxy in the royal northern constellation Cepheus. Near the edge of the region’s massive molecular cloud some 2,400 light-years away, bright reddish emission region Sharpless (Sh) 155 lies at the upper left, also known as the Cave Nebula. About 10 light-years across the cosmic cave’s bright rims of gas are ionized by ultraviolet light from hot young stars. Dusty blue reflection nebulae also abound on the interstellar canvas cut by dense obscuring clouds of dust. The long core of the Lynds Dark Nebula (LDN) 1210 anchors the scene at lower right. Astronomical explorations have revealed other dramatic signs of star formation, including the bright red fleck of Herbig-Haro (HH) 168. Directly below the bright Cave Nebula, the Herbig-Haro object emission is generated by energetic jets from a newborn star.

from NASA http://ift.tt/1KrqKkE
via IFTTT

Is this galaxy jumping through a giant ring of stars? Probably not. Although the precise dynamics behind the featured image is yet unclear, what is clear is that the pictured galaxy, NGC 7714, has been stretched and distorted by a recent collision with a neighboring galaxy. This smaller neighbor, NGC 7715, situated off to the left of the featured frame, is thought to have charged right through NGC 7714. Observations indicate that the golden ring pictured is composed of millions of older Sun-like stars that are likely co-moving with the interior bluer stars. In contrast, the bright center of NGC 7714 appears to be undergoing a burst of new star formation. NGC 7714 is located about 100 million light years away toward the constellation of the Fish (Pisces). The interactions between these galaxies likely started about 150 million years ago and should continue for several hundred million years more, after which a single central galaxy may result.

from NASA http://ift.tt/1T8n1wh
via IFTTT

What’s that glowing in the distance? Although it may look like a lighthouse, the rays of light near the horizon actually emanate from the Temple of Poseidon at Cape Sounion, Greece. Some temple lights are even reflected in the Aegean Sea in the foreground. Although meant to be a monument to the sea, in this image, the temple‘s lights seem to be pointing out locations on the sky. For example, the wide ray toward the right fortuitously points toward the Lagoon Nebula in the central band of our Milky Way, which runs diagonally down the image from the upper left. Also, the nearly vertical beam seems to point toward the star clouds near the direction of the Wild Duck open cluster of stars. The featured image was taken less than three weeks ago.

from NASA http://ift.tt/1AVXgK2
via IFTTT

It’s the dim star, not the bright one, near the center of NGC 3132 that created this odd but beautiful planetary nebula. Nicknamed the Eight-Burst Nebula and the Southern Ring Nebula, the glowing gas originated in the outer layers of a star like our Sun. In this representative color picture, the hot blue pool of light seen surrounding this binary system is energized by the hot surface of the faint star. Although photographed to explore unusual symmetries, it’s the asymmetries that help make this planetary nebula so intriguing. Neither the unusual shape of the surrounding cooler shell nor the structure and placements of the cool filamentary dust lanes running across NGC 3132 are well understood.

from NASA http://ift.tt/1QB5I2W
via IFTTT

Fifty years ago, on June 3, 1965, Edward White stepped out of the orbiting Gemini 4 spacecraft to become the first US astronaut to walk in space. White is captured in this photo taken by mission commander James McDivit from inside the capsule as White’s spacewalk began over the Pacific Ocean on Gemini 4’s third orbit. Planet Earth, spacecraft, and tether are reflected in White’s gold tinted helmet visor. A gas powered manuevering gun is held in his right hand. Though the gun ran out of gas after only 3 minutes, he continued to manuever by twisting his body and pulling on the tether for the remainder of the 23 minute long Extra Vehicular Activity. White later described his historic spacewalk as the most comfortable part of the mission, and said the order to end it was the “saddest moment” of his life.

from NASA http://ift.tt/1AQvP48
via IFTTT

Follow a sunset on a clear day against a distant horizon and you might glimpse a green flash just as the Sun disappears, the sunlight briefly refracted over a long sight-line through atmospheric layers. You can spot a green flash at sunrise too. Pinpointing the exact place and time to see the rising Sun peeking above the horizon is a little more difficult though, and it can be harder still to catch a green flash from the fainter rising Moon. But well-planned snapshots did record a green flash at the Full Moon’s upper edge on June 2nd, from the Roque de los Muchachos Observatory on the Canary Island of La Palma. Looking a little south of due east, this long telephoto view finds the rising Moon above mountains and a sea of clouds. In sunlit profile are the mountaintop Teide Observatory telescope domes on the island of Tenerife some 143 kilometers away.

from NASA http://ift.tt/1MrUcWV
via IFTTT

Three objects stand out in this thoughtful telescopic image, a view toward the mostly stealthy constellation Lynx. The two brightest (the spiky ones) are nearby stars. The third is the remote globular star cluster NGC 2419, at distance of nearly 300,000 light-years. NGC 2419 is sometimes called “the Intergalactic Wanderer”, an appropriate title considering that the distance to the Milky Way’s satellite galaxy, the Large Magellanic Cloud, is only about 160,000 light-years. Roughly similar to other large globular star clusters like Omega Centauri, NGC 2419 is itself intrinsically bright, but appears faint because it is so far away. NGC 2419 may really have an extragalactic origin as, for example, the remains of a small galaxy captured and disrupted by the Milky Way. But its extreme distance makes it difficult to study and compare its properties with other globular clusters that roam the halo of our Milky Way galaxy.

from NASA http://ift.tt/1Q8BcSQ
via IFTTT

Why does this moon look like a sponge? To better investigate, NASA and ESA sent the Saturn-orbiting robotic spacecraft Cassini zooming past Saturn‘s moon Hyperion, once again, earlier this week. One of the images beamed back to Earth is featured above, raw and unprocessed. Visible, as expected, are many unusually shaped craters with an unusual dark material at the bottom. Although Hyperion spans about 250 kilometers, its small gravitational tug on Cassini indicates that it is mostly empty space and so has very low surface gravity. Therefore, the odd shapes of many of Hyperion’s craters are thought to result from impacts that primarily compress and eject surface material — instead of the more typical round craters that appear after a circular shock wave that explosively redistributes surface material. Cassini is on track for another flyby of Saturn‘s Dione in about two weeks.

from NASA http://ift.tt/1FrXpjD
via IFTTT