2016/07/31

Ripples Through a Dark Sky


Sunlight ripples through a dark sky on this Swedish summer midnight as noctilucent or night shining clouds seem to imitate the river below. In fact, the seasonal clouds often appear at high latitudes in corresponding summer months. Also known as polar mesospheric clouds, they form as water vapor is driven into the cold upper atmosphere. Fine dust supplied by disintegrating meteors or volcanic ash provides sites where water vapor can condense, turning to ice at the cold temperatures in the mesosphere. Poised at the edge of space some 80 kilometers above, these icy clouds really do reflect sunlight toward the ground. They are visible here even though the Sun itself was below the horizon, as seen on July 16 from Sweden's Färnebofjärdens National Park. via NASA http://ift.tt/2a7ecFo

2016/07/30

Blue Danube Analemma


The Sun's annual waltz through planet Earth's sky forms a graceful curve known as an analemma. The analemma's figure 8 shape is tipped vertically at far right in this well-composed fisheye view from Budapest, Hungary. Captured at a chosen spot on the western bank of the Danube river, the Sun's position was recorded at 11:44 Central European Time on individual exposures over days spanning 2015 July 23 to 2016 July 4. Of course, on the northern summer solstice the Sun is at the top of the curve, but at the midpoints for the autumn and spring equinoxes. With snow on the ground, the photographer's shadow and equipment bag also appear in the base picture used for the composite panorama, taken on 2016 January 7. On that date, just after the winter solstice, the Sun was leaving the bottom of the beautiful curve over the blue Danube. via NASA http://ift.tt/2aw0M3J

2016/07/29

Space Station View of the Chesapeake Bay


On July 21, 2016, Expedition 48 Commander Jeff Williams of NASA shared this photograph of sunglint illuminating the waters of the Chesapeake Bay, writing, "Morning passing over the Chesapeake Bay heading across the Atlantic." via NASA http://ift.tt/2ahQO9n

2016/07/28

A Black Hole ‘Choir’


The blue dots in this field of galaxies, known as the COSMOS field, show galaxies that contain supermassive black holes emitting high-energy X-rays. via NASA http://ift.tt/2aB7Ifz

M13: A Great Globular Cluster of Stars


M13 is one of the most prominent and best known globular clusters. Visible with binoculars in the constellation of Hercules, M13 is frequently one of the first objects found by curious sky gazers seeking celestials wonders beyond normal human vision. M13 is a colossal home to over 100,000 stars, spans over 150 light years across, lies over 20,000 light years distant, and is over 12 billion years old. At the 1974 dedication of Arecibo Observatory, a radio message about Earth was sent in the direction of M13. The featured image in HDR, taken through a small telescope, spans an angular size just larger than a full Moon, whereas the inset image, taken by Hubble Space Telescope, zooms in on the central 0.04 degrees. via NASA http://ift.tt/2a9rZrY

2016/07/27

The Loneliest Young Star


An unusual celestial object called CX330 was first detected as a source of X-ray light in 2009. It has been launching “jets” of material into the gas and dust around it. via NASA http://ift.tt/2aqttPC

Puzzling a Sky over Argentina


Can you find the comet? True, a careful eye can find thousands of stars, tens of constellations, four planets, three galaxies, and the central band of our Milky Way Galaxy -- all visible in the sky of this spectacular 180-degree panorama. Also, if you know what to look for, you can identify pervasive green airglow, an earthly cloud, the south celestial pole, and even a distant cluster of stars. But these are all easier to find than Comet 252P/LINEAR. The featured image, taken in el Leoncito National Park, Argentina in early April, also features the dome of the Jorge Sahade telescope on the hill on the far right. Have you found the comet yet? If so, good for you (it was the green spot on the left), but really the harder thing to find is Small Cloud of Magellan. via NASA http://ift.tt/2abPyBU

2016/07/26

Cockpit of the First All-Electric Propulsion Aircraft


NASA’s Scalable Convergent Electric Propulsion Technology and Operations Research (SCEPTOR) project has reached a critical milestone, where the electric propulsion integration and conversion of the Tecnam P2006T aircraft into the X-57 will commence. via NASA http://ift.tt/2au7n11

2016/07/25

Hubble Views a Galaxy Fit to Burst


This NASA/ESA Hubble Space Telescope image reveals the vibrant core of the galaxy NGC 3125. Discovered by John Herschel in 1835, NGC 3125 is a great example of a starburst galaxy — a galaxy in which unusually high numbers of new stars are forming, springing to life within intensely hot clouds of gas. via NASA http://ift.tt/2a7K2wJ

M2 9: Wings of a Butterfly Nebula


Are stars better appreciated for their art after they die? Actually, stars usually create their most artistic displays as they die. In the case of low-mass stars like our Sun and M2-9 pictured above, the stars transform themselves from normal stars to white dwarfs by casting off their outer gaseous envelopes. The expended gas frequently forms an impressive display called a planetary nebula that fades gradually over thousands of years. M2-9, a butterfly planetary nebula 2100 light-years away shown in representative colors, has wings that tell a strange but incomplete tale. In the center, two stars orbit inside a gaseous disk 10 times the orbit of Pluto. The expelled envelope of the dying star breaks out from the disk creating the bipolar appearance. Much remains unknown about the physical processes that cause planetary nebulae. via NASA http://ift.tt/29TfmnS

2016/07/24

Summer Planets and Milky Way


Lights sprawl toward the horizon in this night skyscape from Uludag National Park, Bursa Province, Turkey, planet Earth. The stars and nebulae of the Milky Way are still visible though, stretching above the lights on the northern summer night while three other planets shine brightly. Jupiter is at the far right, Mars near the center of the frame, and Saturn is just right of the bulging center of our galaxy. Because the panoramic scene was captured on July 6, all three planets pictured were hosting orbiting, operational, robotic spacecraft from Earth. Popular Mars has five (from three different space agencies): MAVEN (NASA), Mars Orbiter Mission (India), Mars Express (ESA), Mars Odyssey (NASA), Mars Reconnaissance Orbiter (NASA). Ringed Saturn hosts the daring Cassini spacecraft. Just arrived, Juno now orbits ruling gas giant Jupiter. via NASA http://ift.tt/29UT8xW

2016/07/23

Galaxy Cluster Abell S1063 and Beyond


Some 4 billion light-years away, galaxies of massive Abell S1063 cluster near the center of this sharp Hubble Space Telescope snapshot. But the fainter bluish arcs are magnified images of galaxies that lie far beyond Abell S1063. About twice as distant, their otherwise undetected light is magnified and distorted by the cluster's largely unseen gravitational mass, approximately 100 trillion times the mass of the Sun. Providing a tantalizing glimpse of galaxies in the early universe, the effect is known as gravitational lensing. A consequence of warped spacetime it was first predicted by Einstein a century ago. The Hubble image is part of the Frontier Fields program to explore the Final Frontier. via NASA http://ift.tt/2alHNLW

2016/07/22

Aquanauts Splash Down, Beginning NEEMO 21 Research Mission


The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21, 2016, as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, 62 feet below the surface of the Atlantic Ocean. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. via NASA http://ift.tt/2a1syW3

Falcon 9: Launch and Landing


Shortly after midnight on July 18 a SpaceX Falcon 9 rocket launched from Space Launch Complex 40 at Cape Canaveral Air Force Station, Florida, planet Earth. About 9 minutes later, the rocket's first stage returned to the spaceport. This single time exposure captures the rocket's launch arc and landing streak from Jetty Park only a few miles away. Along a climbing, curving trajectory the launch is traced by the initial burn of the first stage, ending near the top of the bright arc before stage separation. Due to perspective the next bright burn appears above the top of the launch arc in the photo, the returning first stage descending closer to the Cape. The final landing burn creates a long streak as the first stage slows and comes to rest at Landing Zone 1. Yesterday the Dragon cargo spacecraft delivered to orbit by the rocket's second stage was attached to the International Space Station. via NASA http://ift.tt/2adChLr

2016/07/21

NASA's Hubble Looks to the Final Frontier


This view of a massive cluster of galaxies unveils a very cluttered-looking universe filled with galaxies near and far. Some are distorted like a funhouse mirror through a "space warp" phenomenon first predicted by Einstein a century ago. via NASA http://ift.tt/2ajiTfA

Dark Dunes on Mars


How does wind affect sand on Mars? To help find out if it differs significantly from Earth, the robotic Curiosity rover on Mars was directed to investigate the dark Namib Dune in the Bagnold Dune Field in Gale Crater. Namib is the first active sand dune investigated up close outside of planet Earth. Wind-created ripples on Earth-bound sand dunes appear similar to ripples on Mars, with one exception. The larger peaks visible on dark Namib dune, averaging about 3 meters apart, are of a type seen only underwater on Earth. They appear to arise on Mars because of the way the thin Martian wind drags dark sand particles. The featured image was taken last December and is horizontally compressed to show context. In the distance, a normal dusty Martian landscape slopes up in light orange, while a rock-strewn landscape is visible on the far right. Curiosity unexpectedly went into safe mode in early July, but it was brought out last week and has now resumed exploring the once lake-filled interior of Gale Crater for further signs that it was once habitable by microbial life. via NASA http://ift.tt/29UT4xX

2016/07/20

Sunset at the Viking Lander 1 Site


On July 20, 1976, at 8:12 a.m. EDT, NASA received the signal that the Viking Lander 1 successfully reached the Martian surface. This major milestone represented the first time the United States successfully landed a vehicle on the surface of Mars, collecting an overwhelming amount of data that would soon be used in future NASA missions. via NASA http://ift.tt/2a90sYR

Color the Universe


Wouldn't it be fun to color in the universe? If you think so, please accept this famous astronomical illustration as a preliminary substitute. You, your friends, your parents or children, can print it out or even color it digitally. While coloring, you might be interested to know that even though this illustration has appeared in numerous places over the past 100 years, the actual artist remains unknown. Furthermore, the work has no accepted name -- can you think of a good one? The illustration, first appearing in a book by Camille Flammarion in 1888, is used frequently to show that humanity's present concepts are susceptible to being supplanted by greater truths. via NASA http://ift.tt/29LI9pW

2016/07/19

Melt Water Over Arctic Sea Ice


Sea ice across the Arctic Ocean is shrinking to below-average levels this summer. NASA’s Operation IceBridge, an airborne survey of polar ice, just completed its first flights studying the aquamarine pools of melt water on the ice surface that may be accelerating the overall sea ice retreat. via NASA http://ift.tt/29RigKX

The Orion Nebula in Infrared from HAWK I


The deepest infrared image of the Orion Nebula has uncovered a bonanza of previously unknown low-mass stars and -- quite possibly -- free floating planets. The picturesque nebula is best known in visible light where it shows a many bright stars and bright glowing gas. Catalogued as M42, the Orion Nebula at a distance of 1300 light years is the closest major star forming region to Earth. One can peer into Orion's pervasive dust in infrared light, as was done again recently with the sophisticated HAWK-I camera attached to one of the European Southern Observatory's Very Large Telescopes in the high mountains of Chile. High resolution versions of the featured infrared deep image show many points of light, many of which are surely brown dwarf stars but some of which are best fit by an unexpectedly high abundance of free-floating planets. Understanding how these low mass objects formed is important to understanding star formation generally and may even help humanity to better understand the early years of our Solar System. via NASA http://ift.tt/29OAIA0

2016/07/18

Not Really Starless at Saturn


Saturn's main rings, along with its and moons, are much brighter than most stars. via NASA http://ift.tt/29IeWgg

Mercury on the Horizon


Have you ever seen the planet Mercury? Because Mercury orbits so close to the Sun, it never wanders far from the Sun in Earth's sky. If trailing the Sun, Mercury will be visible low on the horizon for only a short while after sunset. If leading the Sun, Mercury will be visible only shortly before sunrise. So at certain times of the year, informed skygazers with a little determination can usually pick Mercury out from a site with an unobscured horizon. Above, a lot of determination has been combined with a little digital manipulation to show Mercury's successive positions during March of 2000. Each picture was taken from the same location in Spain when the Sun itself was 10 degrees below the horizon and superposed on the single most photogenic sunset. Currently, Mercury is rising higher above the horizon with each passing sunset, and just now is angularly very close to the brighter planet Venus. via NASA http://ift.tt/29LYlqJ

2016/07/16

NGC 2736: The Pencil Nebula


Moving from top to bottom in the frame near the center of this sharply detailed color composite, thin, bright, braided filaments are actually long ripples in a cosmic sheet of glowing gas seen almost edge-on. The shock wave plows through interstellar space at over 500,000 kilometers per hour. Cataloged as NGC 2736, its elongated appearance suggests its popular name, the Pencil Nebula. The Pencil Nebula is about 5 light-years long and 800 light-years away, but represents only a small part of the Vela supernova remnant. The Vela remnant itself is around 100 light-years in diameter, the expanding debris cloud of a star that was seen to explode about 11,000 years ago. Initially, the shock wave was moving at millions of kilometers per hour but has slowed considerably, sweeping up surrounding interstellar material. In the narrowband, wide field image, red and blue-green colors track the characteristic glow of ionized hydrogen and oxygen atoms. via NASA http://ift.tt/29TYjBd

2016/07/15

Hubble Spots a Secluded Starburst Galaxy


This image, taken by the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys (ACS), shows a starburst galaxy named MCG+07-33-027. This galaxy lies some 300 million light-years away from us, and is currently experiencing an extraordinarily high rate of star formation — a starburst. via NASA http://ift.tt/29JrCFz

NGC 1309: Spiral Galaxy and Friends


A gorgeous spiral galaxy some 100 million light-years distant, NGC 1309 lies on the banks of the constellation of the River (Eridanus). NGC 1309 spans about 30,000 light-years, making it about one third the size of our larger Milky Way galaxy. Bluish clusters of young stars and dust lanes are seen to trace out NGC 1309's spiral arms as they wind around an older yellowish star population at its core. Not just another pretty face-on spiral galaxy, observations of NGC 1309's recent supernova and Cepheid variable stars contribute to the calibration of the expansion of the Universe. Still, after you get over this beautiful galaxy's grand design, check out the array of more distant background galaxies also recorded in this sharp, reprocessed, Hubble Space Telescope view. via NASA http://ift.tt/29z7Evd

2016/07/14

Western Cuba and Gulf of Batabanó


Expedition 48 Commander Jeff Williams of NASA captured photographs of western Cuba and the Gulf of Batabanó as the International Space Station flew overhead. Williams shared this composite image on social media, writing, "Wow! Look at how the navy blue contrasts with the aqua, Gulf of Batabano Cuba." via NASA http://ift.tt/29SEGs9

M7: Open Star Cluster in Scorpius


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 featured wide-angle image was taken near the city of Belo Horizonte in Brazil. 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 on the lower right, and, in the background, literally millions of unrelated stars towards the Galactic center. via NASA http://ift.tt/29BzBl2

2016/07/13

Looking Up at New Work Platforms in the Vehicle Assembly Building


In this view looking up from the floor of the Vehicle Assembly Building at NASA’s Kennedy Space Center, four levels of new work platforms are now installed on the north and south sides of High Bay 3. The G-level work platforms are the fourth of 10 levels that will surround and provide access to the Space Launch System rocket and Orion spacecraft. via NASA http://ift.tt/29ypmhH

Chasing Juno


Wait for me! In 2011, NASA's robotic mission Juno launched for Jupiter from Cape Canaveral, Florida, USA. Last week, Juno reached Jupiter and fired internal rockets to become only the second spacecraft to orbit our Solar System's largest planet. Juno, tasked with studying the jovian giant over the next two years, is in a highly elliptical orbit that will next bringing it near Jupiter's cloud tops in late August. Of course, the three-year-old pictured was not able to catch up to the launching rocket. Today, however, five years later, he is eight-years-old and still chasing rockets -- in that now he wants to be an astronaut. via NASA http://ift.tt/29TCcfx

2016/07/12

Researching 3D Printing Technology on the Space Station


Crew members on the International Space Station re-installed the first 3D printer in orbit, during the week of June 27, 2016, to continue research on the developing technology and how it can be used in space. NASA astronaut Jeff Williams installed the printer in the Microgravity Science Glovebox to begin another round of sample builds. via NASA http://ift.tt/29ESS9C

Aurorae on Jupiter


Jupiter has aurorae. Like Earth, the magnetic field of the gas giant funnels charged particles released from the Sun onto the poles. As these particles strike the atmosphere, electrons are temporarily knocked away from existing gas molecules. Electric force attracts these electrons back. As the electrons recombine to remake neutral molecules, auroral light is emitted. In the featured recently released composite image by the Hubble Space Telescope taken in ultraviolet light, the aurorae appear as annular sheets around the pole. Unlike Earth's aurorae, Jupiter's aurorae include several bright streaks and dots. Jupiter's Great Red Spot is visible on the lower right. Recent aurorae on Jupiter have been particularly strong -- a fortunate coincide with the arrival of NASA's Juno spacecraft at Jupiter last week. Juno was able to monitor the Solar Wind as it approached Jupiter, enabling a better understanding of aurorae in general, including on Earth. via NASA http://ift.tt/29xWBlv

2016/07/11

Paris at Night


Around local midnight time on April 8, 2015, astronauts aboard the International Space Station took this photograph of Paris, often referred to as the “City of Light.” The pattern of the street grid dominates at night, providing a completely different set of visual features from those visible during the day. via NASA http://ift.tt/29rwZuE

Moon Meets Jupiter


What's that next to the Moon? Jupiter -- and its four largest moons. Skygazers around planet Earth enjoyed the close encounter of planets and Moon in 2012 July 15's predawn skies. And while many saw bright Jupiter next to the slender, waning crescent, Europeans also had the opportunity to watch the ruling gas giant pass behind the lunar disk, occulted by the Moon as it slid through the night. Clouds threaten in this telescopic view from Montecassiano, Italy, but the frame still captures Jupiter after it emerged from the occultation along with all four of its large Galilean moons. The sunlit crescent is overexposed with the Moon's night side faintly illuminated by Earthshine. Lined up left to right beyond the dark lunar limb are Callisto, Ganymede, Jupiter, Io, and Europa. In fact, Callisto, Ganymede, and Io are larger than Earth's Moon, while Europa is only slightly smaller. Last week, NASA's Juno became the second spacecraft ever to orbit Jupiter. via NASA http://ift.tt/29vKbjy

2016/07/10

Noctilucent Clouds Tour France


Bright noctilucent or night shining clouds are not familiar sights from northern France. But these electric-blue waves coursed through skies over the small town of Wancourt in Pas-de-Calais on July 6, just before the dawn. From the edge of space, about 80 kilometers above Earth's surface, the icy clouds still reflect sunlight even though the Sun itself is below the horizon as seen from the ground. Usually spotted at high latitudes in summer months the diaphanous apparitions are also known as polar mesospheric clouds. The seasonal clouds are understood to form as water vapor driven into the cold upper atmosphere condenses on the fine dust particles supplied by disintegrating meteors or volcanic ash. NASA's AIM mission provides projections of the noctilucent clouds as seen from space. via NASA http://ift.tt/29DWEBd

2016/07/09

The Swirling Core of the Crab Nebula


At the core of the Crab Nebula lies a city-sized, magnetized neutron star spinning 30 times a second. Known as the Crab Pulsar, it's actually the rightmost of two bright stars, just below a central swirl in this stunning Hubble snapshot of the nebula's core. Some three light-years across, the spectacular picture frames the glowing gas, cavities and swirling filaments bathed in an eerie blue light. The blue glow is visible radiation given off by electrons spiraling in a strong magnetic field at nearly the speed of light. Like a cosmic dynamo the pulsar powers the emission from the nebula, driving a shock wave through surrounding material and accelerating the spiraling electrons. With more mass than the Sun and the density of an atomic nucleus, the spinning pulsar is the collapsed core of a massive star that exploded. The Crab Nebula is the expanding remnant of the star's outer layers. The supernova explosion was witnessed on planet Earth in the year 1054. via NASA http://ift.tt/29ztIqU

2016/07/08

Martian Morse Code


This image of dark dunes on Mars was taken on Feb. 6, 2016, by the HiRISE camera on NASA's Mars Reconnaissance Orbiter. These dunes are influenced by local topography. The shape and orientation of dunes can usually tell us about wind direction, but in this image, the dune-forms are very complex, so it’s difficult to know the wind direction. via NASA http://ift.tt/29nBK4S

The Altiplano Night


The Milky Way is massively bright on this cold, clear, altiplano night. At 4,500 meters its reflection in a river, a volcanic peak on the distant horizon, is captured in this stitched panorama under naturally dark skies of the northern Chilean highlands near San Pedro de Atacama. Along the Solar System's ecliptic plane, the band of Zodiacal light also stands out, extending above the Milky Way toward the upper left. In the scene from late April, brilliant Mars, Saturn, and Antares form a bright celestial triangle where ecliptic meets the center of the Milky Way. Left of the triangle, the large purple-red emission nebula Sharpless 2-27, more than twenty Moon diameters wide is centered around star Zeta Ophiuchi. via NASA http://ift.tt/29n4bzm

2016/07/07

Arp 286: Trio in Virgo


A remarkable telescopic composition in yellow and blue, this scene features a trio of interacting galaxies almost 90 million light-years away, toward the constellation Virgo. On the right, two, spiky, foreground Milky Way stars echo the trio galaxy hues, a reminder that stars in our own galaxy are like those in the distant island universes. With sweeping spiral arms and obscuring dust lanes, NGC 5566 is enormous, about 150,000 light-years across. Just above it lies small, blue NGC 5569. Near center, the third galaxy, NGC 5560, is multicolored and apparently stretched and distorted by its interaction with NGC 5566. The galaxy trio is also included in Halton Arp's 1966 Atlas of Peculiar Galaxies as Arp 286. Of course, such cosmic interactions are now appreciated as a common part of the evolution of galaxies. via NASA http://ift.tt/29h9JKP

Expedition 48 Crew Launches to the International Space Station


The Soyuz MS-01 spacecraft launches from the Baikonur Cosmodrome with Expedition 48. via NASA http://ift.tt/29lNbcQ

2016/07/06

Expedition 48 Soyuz Rollout


The Soyuz MS-01 spacecraft is raised vertical after it was rolled out by train to the launch pad at the Baikonur Cosmodrome, Kazakhstan, Monday, July 4, 2016. NASA astronaut Kate Rubins, cosmonaut Anatoly Ivanishin of Roscosmos, and astronaut Takuya Onishi of JAXA will launch to the International Space Station the evening of July 6 Eastern time. via NASA http://ift.tt/29i0lfb

The Colorful Clouds of Rho Ophiuchi


The many spectacular colors of the Rho Ophiuchi (oh'-fee-yu-kee) clouds highlight the many processes that occur there. The blue regions shine primarily by reflected light. Blue light from the star Rho Ophiuchi and nearby stars reflects more efficiently off this portion of the nebula than red light. The Earth's daytime sky appears blue for the same reason. The red and yellow regions shine primarily because of emission from the nebula's atomic and molecular gas. Light from nearby blue stars - more energetic than the bright star Antares - knocks electrons away from the gas, which then shines when the electrons recombine with the gas. The dark brown regions are caused by dust grains - born in young stellar atmospheres - which effectively block light emitted behind them. The Rho Ophiuchi star clouds, well in front of the globular cluster M4 visible here on the upper right, are even more colorful than humans can see - the clouds emits light in every wavelength band from the radio to the gamma-ray. via NASA http://ift.tt/29fkX38

2016/07/05

Celebrating Juno's Arrival at Jupiter


The Juno team celebrates after receiving confirmation from the spacecraft that it had successfully completed the engine burn and entered orbit of Jupiter, Monday, July 4, 2016 in mission control of the Space Flight Operations Facility at the Jet Propulsion Laboratory. The Juno mission launched August 5, 2011 and will orbit the planet for 20 months. via NASA http://ift.tt/29lHeOj

2016/07/04

Juno Closes in on Jupiter


This is the final view taken by the JunoCam instrument on NASA's Juno spacecraft before Juno's instruments were powered down in preparation for orbit insertion on July 4. via NASA http://ift.tt/29qCfiz

The Cats Eye Nebula


Three thousand light-years away, a dying star throws off shells of glowing gas. This image from the Hubble Space Telescope reveals the Cat's Eye Nebula to be one of the most complex planetary nebulae known. In fact, the features seen in the Cat's Eye are so complex that astronomers suspect the bright central object may actually be a binary star system. The term planetary nebula, used to describe this general class of objects, is misleading. Although these objects may appear round and planet-like in small telescopes, high resolution images reveal them to be stars surrounded by cocoons of gas blown off in the late stages of stellar evolution. via NASA http://ift.tt/29cmB6c

2016/07/03

Firefly Trails and the Summer Milky Way


A camera fixed low to a tripod on a northern summer's eve captured the series of images used in this serene, southern Ontario skyscape. The lakeside view frames our fair galaxy above calm water and the night's quintessential luminous apparitions. But the trails of light are neither satellite glint, nor meteor flash, nor auroral glow. In the wide-field composite constructed with four consecutive 15 second exposures, a pulsing firefly enters at the right, first wandering toward the camera, then left and back toward the lake, the central Milky Way rising in the background. via NASA http://ift.tt/299RfRt

2016/07/02

Juno Approaching Jupiter


Approaching over the north pole after nearly a five-year journey, Juno enjoys a perspective on Jupiter not often seen, even by spacecraft from Earth that usually swing by closer to Jupiter's equator. Looking down toward the ruling gas giant from a distance of 10.9 million kilometers, the spacecraft's JunoCam captured this image with Jupiter's nightside and orbiting entourage of four large Galilean moons on June 21. JunoCam is intended to provide close-up views of the gas giant's cloudy zoned and belted atmosphere. On July 4 (July 5 UT) Juno is set to burn its main engine to slow down and be captured into its own orbit around the giant planet. If all goes well, it will be the first spacecraft to orbit the poles of Jupiter, skimming to within 5,000 kilometers of the Jovian cloud tops during the 20 month mission. via NASA http://ift.tt/298taqm

2016/07/01

Counting Down to Juno's Arrival at Jupiter


A model of the Juno spacecraft is seen at a news briefing on Thursday, June 30, 2016, at the Jet Propulsion Laboratory. The Juno mission will arrive at Jupiter July 4, 2016, to orbit the planet for 20 months and collect data on the planetary core, map the magnetic field, and measure the amount of water and ammonia in the atmosphere. via NASA http://ift.tt/298FMhn

The New World Atlas of Artificial Sky Brightness


How far are you from a naturally dark night sky? In increasing steps, this world map (medium | large) shows the effect of artificial night sky brightness on the visual appearance of the night sky. The brightness was modeled using high resolution satellite data and fit to thousands of night sky brightness measurements in recent work. Color-coded levels are compared to the natural sky brightness level for your location. For example, artificial sky brightness levels in yellow alter the natural appearance of the night sky. In red they hide the Milky Way in an artificial luminous fog. The results indicate that the historically common appearance of our galaxy at night is now lost for more than one-third of humanity. That includes 60% of Europeans and almost 80% of North Americans, along with inhabitants of other densely populated, light-polluted regions of planet Earth. via NASA http://ift.tt/2970a3C

Aurora South of Australia


On June 24, 2016, Expedition 48 Commander Jeff Williams of NASA photographed the brilliant lights of an aurora from the International Space Station. Sharing the image on social media, Williams wrote, "We were treated to some spectacular aurora south of Australia today." via NASA http://ift.tt/2964Ep2