July 9, 2016

Keel-billed Toucan

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The keel-billed toucan (Ramphastos sulfuratus), also known as sulfur-breasted toucan or rainbow-billed toucan, is a colorful Latin American member of the toucan family. It is the national bird of Belize.

Including its bill, the keel-billed toucan ranges in length from around 42 to 55 cm (17 to 22 in). Their large and colorful bill averages around 12–15 cm (4.7–5.9 in), about one-third of its length. It typically weighs about 380–500 g (13–18 oz). While the bill seems large and cumbersome, it is in fact a spongy, hollow bone covered in keratin, a very light and hard protein.

The plumage of the keel-billed toucan is mainly black with a yellow neck and chest. Molting occurs once per year. It has blue feet and red feathers at the tip of its tail. The bill is mainly green with a red tip and orange sides.

Keel-billed toucans have zygodactyl feet (or feet with toes facing in different directions) – two toes face forward and two face back. Because toucans spend a large portion of time in the trees, this helps the birds to stay on the branches of the trees and jump from one branch to another.

The keel-billed toucan can be found from Southern Mexico to Venezuela and Colombia. It roosts in the canopies of tropical, subtropical, and lowland rainforests, up to altitudes of 1,900 m (6,200 ft). It roosts in holes in trees, often with several other toucans. This can be very cramped, so the birds tuck their tails and beaks under their bodies to conserve space while sleeping. Adding to the lack of space, the bottoms of the holes are often covered with pits from the fruit the toucans have eaten.

Like many toucans, keel-billed toucans are very social birds, rarely seen alone. It travels in small flocks of approximately six to twelve individuals through lowland rainforests; it is a poor flyer, and moves mostly by hopping through trees. It has a family structure within the group. Birds will often "duel" with each other using their bills, and throw fruit into each other's mouths. Keel-billed toucans live together in these groups, often sharing cramped living quarters of holes in trees. Able to utilize human-altered habitat to some extent, this widespread bird is considered to be a Species of Least Concern by the IUCN. However, they are still threatened by hunting for their meat and beaks, and toucan populations are on a decreasing trend.

The diet of keel-billed toucans consists mostly of a wide range of fruit, but may also include insects, eggs, nestlings and lizards, as well as small birds. The bill, surprisingly dexterous, allows this toucan to utilize a large variety of fruit that might not otherwise be reached. When eating the fruit, it uses its bill to dissect the fruit, and then tosses its head back to swallow the fruit whole.

The female keel-billed toucan will lay 1–4 white eggs in a natural or already-made tree cavity. The male and female share in the caring of the eggs, both taking turns incubating. The eggs hatch approximately 15–20 days after being laid. After hatching, the male and female again take turns feeding the chicks. When the chicks hatch, they have no feathers, and have their eyes closed for approximately 3 weeks. The chicks have adequately formed heel pads, which assist on the pit-covered bottom of the nest. The chicks stay in their nest for approximately eight to nine weeks while their bills develop fully and they are ready to fledge from the nest.

Explanation from: https://en.wikipedia.org/wiki/Keel-billed_toucan

The Omega Nebula (Messier 17)

Omega Nebula Messier 17

This image of the Omega Nebula, captured by ESO's Very Large Telescope (VLT), is one of the sharpest of this object ever taken from the ground. It shows the dusty, rose-coloured central parts of this famous stellar nursery and reveals extraordinary detail in the cosmic landscape of gas clouds, dust and newborn stars.

The colourful gas and dark dust in the Omega Nebula serve as the raw materials for creating the next generation of stars. In this particular section of the nebula, the newest stars on the scene — dazzlingly bright and shining blue-white — light up the whole ensemble. The nebula's smoky-looking ribbons of dust stand in silhouette against the glowing gas. The dominant reddish colours of this portion of the cloud-like expanse, arise from hydrogen gas, glowing under the influence of the intense ultraviolet rays from the hot young stars.

The Omega Nebula goes by many names, depending on who observed it when and what they thought they saw. These other titles include the Swan Nebula, the Horseshoe Nebula and even the Lobster Nebula. The object has also been catalogued as Messier 17 (M17) and NGC 6618. The nebula is located about 6500 light-years away in the constellation of Sagittarius (The Archer). A popular target of astronomers, this illuminated gas and dust field ranks as one of the youngest and most active stellar nurseries for massive stars in the Milky Way.

The image was taken with the FORS (FOcal Reducer and Spectrograph) instrument on Antu, one of the four Unit Telescopes of the VLT. In addition to the huge telescope, exceptionally steady air during the observations, despite some clouds, also helped make the crispness of this image possible. As a result this new picture is among the sharpest of this part of the Omega Nebula ever taken from the ground.

Image Credit: ESO
Explanation from: https://www.eso.org/public/images/eso1201a/

Artist’s impression of planet orbiting in the HD 131399 system

triple star system HD 131399

This artists impression shows the orbit of the planet in the triple-star system HD 131399. Two of the stars are close together and the third, brighter component is orbited by a gas giant planet named HD 131399Ab.

Located about 320 light-years from Earth in the constellation of Centaurus (The Centaur), HD 131399Ab is about 16 million years old, making it also one of the youngest exoplanets discovered to date, and one of very few directly-imaged planets. With a temperature of around 580 degrees Celsius and an estimated mass of four Jupiter masses, it is also one of the coldest and least massive directly-imaged exoplanets.

Video Credit: ESO/L. Calçada/M. Kornmesser
Explanation from: https://www.eso.org/public/videos/eso1624a/

July 8, 2016

Southwestern Australia seen from the International Space Station

Australia from ISS

The Sun is about to set in this scene showing parts of southwestern Australia, which was photographed by one of the Expedition 35 crew members aboard the International Space Station on April 1, 2013. Several of the orbital outpost's solar array panels are seen in the foreground.

Image Credit: NASA

Core of the Crab Nebula

Core of the Crab Nebula

At the center of the Crab Nebula, located in the constellation Taurus, lies a celestial "beating heart" that is an example of extreme physics in space. The tiny object blasts out blistering pulses of radiation 30 times a second with unbelievable clock-like precision. Astronomers soon figured out that it was the crushed core of an exploded star, called a neutron star, which wildly spins like a blender on puree. The burned-out stellar core can do this without flying apart because it is 10 billion times stronger than steel. This incredible density means that the mass of 1.4 suns has been crushed into a solid ball of neutrons no bigger than the width of a large city. This Hubble image captures the region around the neutron star. It is unleashing copious amounts of energy that are pushing on the expanding cloud of debris from the supernova explosion — like an animal rattling its cage. This includes wave-like tsunamis of charged particles embedded in deadly magnetic fields.

On July 4, 1054, Chinese astronomers recorded the supernova that formed the Crab Nebula. The ultimate celestial firework, this "guest star" was visible during the daytime for 23 days, shining six times brighter than the planet Venus. The supernova was also recorded by Japanese, Arabic, and Native American stargazers. While searching for a comet that was predicted to return in 1758, French astronomer Charles Messier discovered a hazy nebula in the direction of the long-vanished supernova. He would later add it to his celestial catalog as "Messier 1." Because M1 didn't move across the sky like a comet, Messier simply ignored it other than just marking it as a "fake comet." Nearly a century later the British astronomer William Parsons sketched the nebula. Its resemblance to a crustacean led to M1's other name, the Crab Nebula. In 1928 Edwin Hubble first proposed associating the Crab Nebula to the Chinese "guest star" of 1054.

Image Credit: NASA and ESA
Explanation from: http://hubblesite.org/newscenter/archive/releases/2016/26

The triple-star system HD 131399

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A team of astronomers have used the SPHERE instrument on ESO’s Very Large Telescope to image the first planet ever found in a wide orbit inside a triple-star system. The orbit of such a planet had been expected to be unstable, probably resulting in the planet being quickly ejected from the system. But somehow this one survives. This unexpected observation suggests that such systems may actually be more common than previously thought.

Luke Skywalker's home planet, Tatooine, in the Star Wars saga, was a strange world with two suns in the sky, but astronomers have now found a planet in an even more exotic system, where an observer would either experience constant daylight or enjoy triple sunrises and sunsets each day, depending on the seasons, which last longer than human lifetimes.

This world has been discovered by a team of astronomers led by the University of Arizona, USA, using direct imaging at ESO’s Very Large Telescope (VLT) in Chile. The planet, HD 131399Ab, is unlike any other known world — its orbit around the brightest of the three stars is by far the widest known within a multi-star system. Such orbits are often unstable, because of the complex and changing gravitational attraction from the other two stars in the system, and planets in stable orbits were thought to be very unlikely.

Located about 320 light-years from Earth in the constellation of Centaurus (The Centaur), HD 131399Ab is about 16 million years old, making it also one of the youngest exoplanets discovered to date, and one of very few directly imaged planets. With a temperature of around 580 degrees Celsius and an estimated mass of four Jupiter masses, it is also one of the coldest and least massive directly-imaged exoplanets.

"HD 131399Ab is one of the few exoplanets that have been directly imaged, and it's the first one in such an interesting dynamical configuration," said Daniel Apai, from the University of Arizona, USA, and one of the co-authors of the new paper.

"For about half of the planet’s orbit, which lasts 550 Earth-years, three stars are visible in the sky; the fainter two are always much closer together, and change in apparent separation from the brightest star throughout the year," adds Kevin Wagner, the paper's first author and discoverer of HD 131399Ab.

Kevin Wagner, who is a PhD student at the University of Arizona, identified the planet among hundreds of candidate planets and led the follow-up observations to verify its nature.

The planet also marks the first discovery of an exoplanet made with the SPHERE instrument on the VLT. SPHERE is sensitive to infrared light, allowing it to detect the heat signatures of young planets, along with sophisticated features correcting for atmospheric disturbances and blocking out the otherwise blinding light of their host stars.

Although repeated and long-term observations will be needed to precisely determine the planet's trajectory among its host stars, observations and simulations seem to suggest the following scenario: the brightest star is estimated to be eighty percent more massive than the Sun and dubbed HD 131399A, which itself is orbited by the less massive stars, B and C, at about 300 au (one au, or astronomical unit, equals the average distance between the Earth and the Sun). All the while, B and C twirl around each other like a spinning dumbbell, separated by a distance roughly equal to that between the Sun and Saturn (10 au).

In this scenario, planet HD 131399Ab travels around the star A in an orbit with a radius of about 80 au, about twice as large as Pluto’s in the Solar System, and brings the planet to about one third of the separation between star A and the B/C star pair. The authors point out that a range of orbital scenarios is possible, and the verdict on the long-term stability of the system will have to wait for planned follow-up observations that will better constrain the planet’s orbit.

"If the planet was further away from the most massive star in the system, it would be kicked out of the system," Apai explained. "Our computer simulations have shown that this type of orbit can be stable, but if you change things around just a little bit, it can become unstable very quickly."

Planets in multi-star systems are of special interest to astronomers and planetary scientists because they provide an example of how the mechanism of planetary formation functions in these more extreme scenarios. While multi-star systems seem exotic to us in our orbit around our solitary star, multi-star systems are in fact just as common as single stars.

"It is not clear how this planet ended up on its wide orbit in this extreme system, and we can't say yet what this means for our broader understanding of the types of planetary systems, but it shows that there is more variety out there than many would have deemed possible," concludes Kevin Wagner. "What we do know is that planets in multi-star systems have been studied far less often, but are potentially just as numerous as planets in single-star systems."

Image Credit: ESO/L. Calçada
Explanation from: https://www.eso.org/public/unitedkingdom/news/eso1624/

July 7, 2016

Mount Everest

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Mount Everest, also known in Nepal as Sagarmāthā and in Tibet as Chomolungma, is Earth's highest mountain. It is located in the Mahalangur mountain range in Nepal and Tibet. Its peak is 8,848 metres (29,029 ft) above sea level. The international border between China (Tibet Autonomous Region) and Nepal runs across Everest's precise summit point. Its massif includes neighbouring peaks Lhotse, 8,516 m (27,940 ft); Nuptse, 7,855 m (25,771 ft) and Changtse, 7,580 m (24,870 ft).

In 1856, the Great Trigonometrical Survey of India established the first published height of Everest, then known as Peak XV, at 8,840 m (29,002 ft). The current official height of 8,848 m (29,029 ft) as recognised by China and Nepal was established by a 1955 Indian survey and subsequently confirmed by a Chinese survey in 1975. In 1865, Everest was given its official English name by the Royal Geographical Society upon a recommendation by Andrew Waugh, the British Surveyor General of India. As there appeared to be several different local names, Waugh chose to name the mountain after his predecessor in the post, Sir George Everest, despite George Everest's objections.

Mount Everest attracts many climbers, some of them highly experienced mountaineers. There are two main climbing routes, one approaching the summit from the southeast in Nepal (known as the standard route) and the other from the north in Tibet. While not posing substantial technical climbing challenges on the standard route, Everest presents dangers such as altitude sickness, weather, wind as well as significant objective hazards from avalanches and the Khumbu Icefall. As of 2016, there are well over 200 corpses still on the mountain, with some of them even serving as landmarks.

The first recorded efforts to reach Everest's summit were made by British mountaineers. With Nepal not allowing foreigners into the country at the time, the British made several attempts on the north ridge route from the Tibetan side. After the first reconnaissance expedition by the British in 1921 reached 7,000 m (22,970 ft) on the North Col, the 1922 expedition pushed the North ridge route up to 8,320 m (27,300 ft) marking the first time a human had climbed above 8,000 m (26,247 ft). Tragedy struck on the descent from the North col when seven porters were killed in an avalanche.

The 1924 expedition resulted in the greatest mystery on Everest to this day: George Mallory and Andrew Irvine made a final summit attempt on 8 June but never returned, sparking debate as to whether they were the first to reach the top. They had been spotted high on the mountain that day but disappeared in the clouds, never to be seen again, until Mallory's body was found in 1999 at 8,155 m (26,755 ft) on the North face.

Tenzing Norgay and Edmund Hillary made the first official ascent of Everest in 1953 using the southeast ridge route. Tenzing had reached 8,595 m (28,199 ft) the previous year as a member of the 1952 Swiss expedition. The Chinese mountaineering team of Wang Fuzhou, Gonpo and Qu Yinhua made the first reported ascent of the peak from the North Ridge on 25 May 1960.

Explanation from: https://en.wikipedia.org/wiki/Mount_Everest

Cassiopeia A

Cassiopeia A

This stunning picture of the supernova remnant Cassiopeia A (Cas A) is a composite of images taken by three of NASA's Great Observatories. Infrared data from the Spitzer Space Telescope are colored red; optical data from the Hubble Space Telescope are yellow; and X-ray data from the Chandra X-ray Observatory are green and blue.

Cas A is the 300-year-old remnant created by the supernova explosion of a massive star. Each Great Observatory image highlights different characteristics of the remnant. Spitzer reveals warm dust in the outer shell with temperatures of about 10 degrees Celsius (80 degrees Fahrenheit), and Hubble sees the delicate filamentary structures of warmer gases about 10,000 degrees Celsius. Chandra shows hot gases at about 10 million degrees Celsius. This hot gas was created when ejected material from the supernova smashed into surrounding gas and dust at speeds of about ten million miles per hour.

A comparison of the infrared and X-ray images of Cas A should enable astronomers to better understand how relatively cool dust grains can coexist in the superhot gas that produces the X-rays. It should also help to determine whether most of the dust in the supernova remnant came from the massive star before it exploded, or from the rapidly expanding supernova ejecta.

The turquoise dot at the center of the shell may be a neutron star created during the supernova. Blue Chandra data were acquired using broadband X-rays (low through high energies); green Chandra data correspond only to intermediate energy X-rays; yellow Hubble data were taken using a 900 nanometer-wavelength filter, and red Spitzer data are from the telescope's 24-micron detector.

Image Credit: X-ray: NASA/CXC/SAO; Optical: NASA/STScI; Infrared: NASA/JPL-Caltech/Steward/O.Krause et al.
Explanation from: http://chandra.si.edu/photo/2005/casa/

The Glow of the Lagoon Nebula

Lagoon Nebula Messier 8

Gas and dust condense, beginning the process of creating new stars in this image of Messier 8, also known as the Lagoon Nebula. Located four to five thousand light-years away, in the constellation of Sagittarius (the Archer), the nebula is a giant interstellar cloud, one hundred light-years across. It boasts many large, hot stars, whose ultraviolet radiation sculpts the gas and dust into unusual shapes. Two of these giant stars illuminate the brightest part of the nebula, known as the Hourglass Nebula, a spiralling, funnel-like shape near its centre.

Messier 8 is one of the few star-forming nebulae visible to the unaided eye, and was discovered as long ago as 1747, although the full range of colours wasn’t visible until the advent of more powerful telescopes. The Lagoon Nebula derives its name from the wide lagoon-shaped dark lane located in the middle of the nebula that divides it into two glowing sections.

This image combines observations performed through three different filters (B, V, R) with the 1.5-metre Danish telescope at the ESO La Silla Observatory in Chile.

Image Credit: ESO/IDA/Danish 1.5 m/ R. Gendler, U.G. Jørgensen, K. Harpsøe
Explanation from: https://www.eso.org/public/images/potw1016a/

July 6, 2016

Jellyfish Lake

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Jellyfish Lake is a marine lake located on Eil Malk island in Palau. Eil Malk is part of the Rock Islands, a group of small, rocky, mostly uninhabited islands in Palau's Southern Lagoon, between Koror and Peleliu. There are about 70 other marine lakes located throughout the Rock Islands. Millions of golden jellyfish migrate horizontally across the lake daily.

Jellyfish Lake is connected to the ocean through fissures and tunnels in the limestone of an ancient Miocene reef. However the lake is sufficiently isolated and the conditions are different enough that the diversity of species in the lake is greatly reduced from the nearby lagoon. The golden jellyfish, Mastigias cf. papua etpisoni, and possibly other species in the lake have evolved to be substantially different from their close relatives living in the nearby lagoons.

Explanation from: https://en.wikipedia.org/wiki/Jellyfish_Lake

The North America Nebula

The North America Nebula

This image is a composite from black and white images taken with the Palomar Observatory's 48-inch (1.2 meter) Samuel Oschin Telescope as a part of the second National Geographic Palomar Observatory Sky Survey (POSS II). The images were recorded on two glass photographic plates - one sensitive to red light and the other to blue and later they were digitized. In order to produce the colour image seen here a total of 62 different frames were processed - 31 frames for each colour band, coming from 4 different plates taken from 1990 to 1993. The original file is 14,264 x 15,429 pixels with a resolution of about 1 arc-second per pixel. The image covers an area of sky larger than 4› x 4.3› (for comparison, the Full Moon is about 0.5› in diameter).

Image Credit: Davide De Martin (ESA/Hubble), the ESA/ESO/NASA & Digitized Sky Survey 2
Explanation from: https://www.spacetelescope.org/images/heic0510a/

Artist's impression of the Supermassive Black Hole

Artist's impression of the Supermassive Black Hole

In this artist's rendering, a thick accretion disk has formed around a supermassive black hole following the tidal disruption of a star that wandered too close. Stellar debris has fallen toward the black hole and collected into a thick chaotic disk of hot gas. Flashes of X-ray light near the center of the disk result in light echoes that allow astronomers to map the structure of the funnel-like flow, revealing for the first time strong gravity effects around a normally quiescent black hole.

Image Credit: NASA/Swift/Aurore Simonnet, Sonoma State Univ.
Explanation from: https://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=12265

July 5, 2016

Red Lionfish

Red Lionfish

The red lionfish (Pterois volitans) is a venomous coral reef fish in the family Scorpaenidae, order Scorpaeniformes. P. volitans is natively found in the Indo-Pacific region, but has become an invasive problem in the Caribbean Sea, as well as along the East Coast of the United States. This and a similar species, Pterois miles, have both been deemed as invasive species. Red lionfish are clad in white stripes alternated with red/maroon/brown stripes. Adults in this species can grow as large as 47 cm (18.5 in) in length, making it one of the largest species of lionfish in the ocean, while juveniles are typically shorter than 1 inch (2.5 cm). The average red lionfish lives around 10 years. As with many species within the Scopaenidae family, it has large, venomous spines that protrude from the body, similar to a mane, giving it the common name lionfish. The venomous spines make the fish inedible or deter most potential predators. Lionfish reproduce monthly and are able to quickly disperse during their larval stage for expansion of their invasive region. No definitive predators of the lionfish are known, and many organizations are promoting the harvest and consumption of lionfish in efforts to prevent further increases in the already high population densities.

Image Credit: Jens Petersen
Explanation from: https://en.wikipedia.org/wiki/Red_lionfish

Spiral Galaxy Messier 83

Spiral Galaxy Messier 83

This Hubble image shows the spiral galaxy Messier 83, otherwise known as the Southern Pinwheel Galaxy. One of the largest and closest barred spirals to us, this galaxy is dramatic and mysterious; it has hosted a large number of supernova explosions, and is thought to have a double nucleus lurking at its core.

Messier 83 is not one to blend into the background. Located some 15 million light-years away in the constellation of Hydra (The Sea Serpent), it is one of the most conspicuous galaxies of its type in our skies. It is a prominent member of a group of galaxies known as the Centaurus A/M83 Group, which also counts dusty Centaurus A and irregular NGC 5253 as members.

Spiral galaxies come in a range of types depending on their appearance and structure — for example, how tightly wound their arms are, and the characteristics of the central bulge. Messier 83 has a "bar" of stars slicing through its centre, leading to its classification as a barred spiral. The Milky Way also belongs to this category.

These bars are thought to act a bit like a funnel, channelling gas inwards towards the galaxy's centre. This gas is then used to form new stars and also to feed the galaxy's central black hole, explaining why many barred spirals — including Messier 83 — have very active and luminous central regions.

However, Messier 83's centre is mysterious and unusual; the supermassive black hole at its heart is not alone. This striking spiral displays a phenomenon known as a double nucleus — a feature that has also been spotted in the Andromeda Galaxy, the nearest spiral galaxy to us. This does not mean that Messier 83 contains two central black holes, but that its single supermassive black hole may be ringed by a lopsided disc of stars, which orbits around the black hole and creates the appearance of a dual core.

As well as this double nucleus, Messier 83 has hosted quite a few supernova explosions — six in total that we have observed (SN 1923A, SN 1945B, SN 1950B, SN 1957D, SN 1968L, and SN 1983N). This number is matched by only two other galaxies: Messier 61 which also has six, and NGC 6946, which tops the list with nine. As well as these explosions, almost 300 supernova remnants — the older leftovers from exploded stars — have been found within Messier 83, detected using the data that make up this image. These observations are being used to study the life cycle of stars. As well as these old remnants, some 3000 star clusters have been identified in Messier 83, some of which are very young at under 5 million years old.

This mosaic image uses observations taken by Hubble's Wide Field Camera 3. It shows the galaxy in full, with dark dust lanes, fiery red patches of gas, and bright blue patches of recent star formation speckled across the spiralling arms. Although it looks sprawling, Messier 83 is just under half of the size of the Milky Way.

Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA), William Blair
Explanation from: https://www.spacetelescope.org/news/heic1403/

The Crab Nebula

Crab Nebula

This image shows a composite view of the Crab nebula, an iconic supernova remnant in our Milky Way galaxy, as viewed by the Herschel Space Observatory and the Hubble Space Telescope. Herschel is a European Space Agency (ESA) mission with important NASA contributions, and Hubble is a NASA mission with important ESA contributions.

A wispy and filamentary cloud of gas and dust, the Crab nebula is the remnant of a supernova explosion that was observed by Chinese astronomers in the year 1054.

The image combines Hubble's view of the nebula at visible wavelengths, obtained using three different filters sensitive to the emission from oxygen and sulphur ions and is shown here in blue. Herschel's far-infrared image reveals the emission from dust in the nebula and is shown here in red.

While studying the dust content of the Crab nebula with Herschel, a team of astronomers have detected emission lines from argon hydride, a molecular ion containing the noble gas argon. This is the first detection of a noble-gas based compound in space.

The Herschel image is based on data taken with the Photoconductor Array Camera and Spectrometer (PACS) instrument at a wavelength of 70 microns; the Hubble image is based on archival data from the Wide Field and Planetary Camera 2 (WFPC2).

Image Credit: NASAESA/Herschel/PACS/Allison Loll/Jeff Hester
Explanation from: http://www.nasa.gov/jpl/herschel/crab-nebula-pia17563

July 4, 2016

Jupiter seen by NASA's Juno spacecraft

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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. Juno obtained this color view on June 29, 2016, at a distance of 3.3 million miles (5.3 million kilometers) from Jupiter.

The spacecraft is approaching over Jupiter's north pole, providing an unprecedented perspective on the Jupiter system, including its four large moons.

Image Credit: NASA/JPL-Caltech/SwRI/MSSS

Supernova Remnant NGC 2060

Supernova Remnant NGC 2060

Located in the direction of the constellation Dorado in the Large Magellanic Cloud, the resplendent object known as NGC 2060 is the aftermath of a supernova. These powerful explosions serve as the death knell for massive stars, blasting heated matter out into surrounding space at great speed.

Image Credit: ESO

Artist's impression of the evaporation of HD 189733b's atmosphere in response to a powerful eruption from its host star

Artist's impression of the evaporation of HD 189733b's atmosphere in response to a powerful eruption from its host star

An international team of astronomers using data from NASA's Hubble Space Telescope made an unparalleled observation, detecting significant changes in the atmosphere of a planet located beyond our solar system.

Exoplanet HD 189733b lies so near its star that it completes an orbit every 2.2 days. In late 2011, NASA's Hubble Space Telescope found that the planet's upper atmosphere was streaming away at speeds exceeding 300,000 mph. Just before the Hubble observation, NASA's Swift detected the star blasting out a strong X-ray flare, one powerful enough to blow away part of the planet's atmosphere.

The exoplanet is a gas giant similar to Jupiter, but about 14 percent larger and more massive. The planet circles its star at a distance of only 3 million miles, or about 30 times closer than Earth's distance from the Sun. Its star, named HD 189733A, is about 80 percent the size and mass of our Sun.

Image Credit: ESO/J. Emerson/VISTA
Explanation from: http://www.nasa.gov/multimedia/imagegallery/image_feature_2304.html

Great Lakes seen from the International Space Station

Great Lakes from ISS

From the vantage point of the International Space Station (ISS), astronauts observe many spectacular phenomena, including aurora, noctilucent clouds, airglow, and sunglint on Earth’s water bodies. Sunglint is light reflected off of a water surface towards the observer, such that it creates the appearance of a mirror-like surface.

If the viewing and lighting conditions are ideal, that mirror-like surface can extend over very large areas, such as the entire surface of Lake Ontario (approximately 18,960 square kilometers). This astronaut photograph was taken while the ISS was located over a point to the southeast of Nova Scotia, approximately 1,200 kilometers (740 miles) ground distance from the centerpoint of the image. Lake Ontario, Lake Huron, the Finger Lakes of New York, and numerous other bodies of water appear brilliantly lit by sunglint. To the west, Lake Erie is also highlighted by sunglint, but less light is being reflected towards the astronaut observer, resulting in a duller appearance.

Much of central Canada is obscured by extensive cloud cover in the image, whereas a smaller grouping of clouds obscures the Appalachian range and Pennsylvania (image lower left). The blue envelope of the Earth’s atmosphere is visible above the curved limb, or horizon line, that extends across the upper third of the image. Such panoramic views of the planet are readily taken with handheld digital cameras through ISS viewing ports, which allow the astronaut to take advantage of the full range of viewing angles.

Image Credit: NASA
Explanation from: http://earthobservatory.nasa.gov/IOTD/view.php?id=78617

July 3, 2016

Great Blue Hole

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The Great Blue Hole is a giant submarine sinkhole off the coast of Belize. It lies near the center of Lighthouse Reef, a small atoll 70 km (43 mi) from the mainland and Belize City. The hole is circular in shape, over 300 m (984 ft) across and 124 m (407 ft) deep. It was formed during several episodes of quaternary glaciation when sea levels were much lower. Analysis of stalactites found in the Great Blue Hole shows that formation took place 153,000; 66,000; 60,000; and 15,000 years ago. As the ocean began to rise again, the cave was flooded. The Great Blue Hole is a part of the larger Belize Barrier Reef Reserve System, a World Heritage Site of the United Nations Educational, Scientific and Cultural Organization (UNESCO).

Explanation from: https://en.wikipedia.org/wiki/Great_Blue_Hole

Star Formation in Orion (Messier 78)

Star Formation in Orion (Messier 78)

Looking like a pair of eyeglasses only a rock star would wear, this nebula brings into focus a murky region of star formation. NASA's Spitzer Space Telescope exposes the depths of this dusty nebula with its infrared vision, showing stellar infants that are lost behind dark clouds when viewed in visible light.

Best known as Messier 78, the two round greenish nebulae are actually cavities carved out of the surrounding dark dust clouds. The extended dust is mostly dark, even to Spitzer's view, but the edges show up in mid-wavelength infrared light as glowing, red frames surrounding the bright interiors. Messier 78 is easily seen in small telescopes in the constellation of Orion, just to the northeast of Orion's belt, but looks strikingly different, with dominant, dark swaths of dust. Spitzer's infrared eyes penetrate this dust, revealing the glowing interior of the nebulae.

A string of baby stars that have yet to burn their way through their natal shells can be seen as red pinpoints on the outside of the nebula. Eventually these will blossom into their own glowing balls, turning this two-eyed eyeglass into a many-eyed monster of a nebula.

This is a three-color composite that shows infrared observations from two Spitzer instruments. Blue represents 3.6- and 4.5-micron light, and green shows light of 5.8 and 8 microns, both captured by Spitzer's infrared array camera. Red is 24-micron light detected by Spitzer's multiband imaging photometer.

Image Credit: NASA/JPL-Caltech
Explanation from: https://www.nasa.gov/multimedia/imagegallery/image_feature_2078.html

Auroras in Jupiter's Atmosphere seen by Hubble Space Telescope

Jupiter Aurora

This composite video illustrates the auroras on Jupiter relative to their position on the giant planet. As on Earth, auroras are produced by the interaction of a planet's magnetic field with its atmosphere. The Jupiter auroras observed by Hubble Space Telescope are some of the most active and brightest ever caught by Hubble, reaching intensities over a thousand times brighter than those seen on Earth. Hubble's sensitivity to ultraviolet light captures the glow of the auroras above Jupiter's cloud top.

Video Credit: NASA, ESA, J. Nichols, G. Bacon (STScI), A. Simon (GSFC) and the OPAL team
Explanation from: http://hubblesite.org/newscenter/archive/releases/2016/24/video/c/