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Sep 30, 2019

Orion Rising over Brazil Orion Rising over Brazil


Have you seen Orion lately? The next few months will be the best for seeing this familiar constellation as it rises continually earlier in the night. However, Orion's stars and nebulas won't look quite as colorful to the eye as they do in this fantastic camera image. In the featured image, Orion was captured by camera showing its full colors last month over a Brazilian copal tree from Brazil's Central-West Region. Here the cool red giant Betelgeuse takes on a strong orange hue as the brightest star on the far left. Otherwise, Orion's hot blue stars are numerous, with supergiant Rigel balancing Betelgeuse at the upper right, Bellatrix at the upper left, and Saiph at the lower right. Lined up in Orion's belt (bottom to top) are Alnitak, Alnilam, and Mintaka all about 1,500 light-years away, born of the constellation's well studied interstellar clouds. And if a "star" toward the upper right Orion's sword looks reddish and fuzzy to you, it should. It's the stellar nursery known as the Great Nebula of Orion. via NASA https://ift.tt/2nK8Jfr

Sep 29, 2019

MyCn 18: The Engraved Hourglass Planetary Nebula MyCn 18: The Engraved Hourglass Planetary Nebula


Do you see the hourglass shape -- or does it see you? If you can picture it, the rings of MyCn 18 trace the outline of an hourglass -- although one with an unusual eye in its center. Either way, the sands of time are running out for the central star of this hourglass-shaped planetary nebula. With its nuclear fuel exhausted, this brief, spectacular, closing phase of a Sun-like star's life occurs as its outer layers are ejected - its core becoming a cooling, fading white dwarf. In 1995, astronomers used the Hubble Space Telescope (HST) to make a series of images of planetary nebulae, including the one featured here. Pictured, delicate rings of colorful glowing gas (nitrogen-red, hydrogen-green, and oxygen-blue) outline the tenuous walls of the hourglass. The unprecedented sharpness of the Hubble images has revealed surprising details of the nebula ejection process that are helping to resolve the outstanding mysteries of the complex shapes and symmetries of planetary nebulas like MyCn 18. via NASA https://ift.tt/2nxkKoo

Sep 28, 2019

An Analemma of the Sun An Analemma of the Sun


This week the equinox found the Sun near the middle, but not at the crossing point, of an analemma in its annual trek through planet Earth's skies. In this scenic view, that graceful, figure-8-shaped curve was intentionally posed above the iconic Danube River and the capital city of Hungary. Looking south from Budapest's Margaret Bridge it combines digital frames taken at exactly the same time of day (11:44 CET) on dates between 2018 September 24 and 2019 September 15. That puts the metropolitan Pest on the left, regal Buda on the right, and the positions of the Sun on the solstice dates at the top and bottom of the analemma curve. December's near solstice Sun is just hidden behind a dramatic cloud bank. via NASA https://ift.tt/2lSdQtq

Sep 27, 2019

The Annotated Galactic Center The Annotated Galactic Center


The center of our Milky Way galaxy can be found some 26,000 light-years away toward the constellation Sagittarius. Even on a dark night, you can't really see it though. Gaze in that direction, and your sight-line is quickly obscured by intervening interstellar dust. In fact, dark dust clouds, glowing nebulae, and crowded starfieds are packed along the fertile galactic plane and central regions of our galaxy. This annotated view, a mosaic of dark sky images, highlights some favorites, particularly for small telescope or binocular equipped skygazers. The cropped version puts the direction to the galactic center on the far right. It identifies well-known Messier objects like the Lagoon nebula (M8), the Trifid (M20), star cloud M24, and some of E.E. Barnard's dark markings on the sky. A full version extends the view to the right toward the constellation Scorpius, in all covering over 20 degrees across the center of the Milky Way. via NASA https://ift.tt/2n9bTZy

Sep 26, 2019

Da Vinci Rise Da Vinci Rise


An old Moon rose this morning, its waning sunlit crescent shining just above the eastern horizon before sunrise. But earthshine, light reflected from a bright planet Earth, lit the shadowed portion of the lunar disk and revealed most of a familiar lunar near side to early morning risers. In fact, a description of earthshine in terms of sunlight reflected by Earth's oceans illuminating the Moon's dark surface was written over 500 years ago by Leonardo da Vinci. One lunation ago this old Moon also rose above the eastern horizon. Its sunlit crescent and da Vinci glow were captured in stacked exposures from the Badain Jilin Desert of Inner Mongolia, China on August 29, 2019. This year marks the 500th anniversary of Leondardo da Vinci's death. via NASA https://ift.tt/2lR23LQ

Sep 25, 2019

The Pelican Nebula in Gas, Dust, and Stars The Pelican Nebula in Gas, Dust, and Stars


The Pelican Nebula is slowly being transformed. IC 5070, the official designation, is divided from the larger North America Nebula by a molecular cloud filled with dark dust. The Pelican, however, receives much study because it is a particularly active mix of star formation and evolving gas clouds. The featured picture was produced in three specific colors -- light emitted by sulfur, hydrogen, and oxygen -- that can help us to better understand these interactions. The light from young energetic stars is slowly transforming the cold gas to hot gas, with the advancing boundary between the two, known as an ionization front, visible in bright orange on the right. Particularly dense tentacles of cold gas remain. Millions of years from now this nebula might no longer be known as the Pelican, as the balance and placement of stars and gas will surely leave something that appears completely different. via NASA https://ift.tt/2kWTUF8

Sep 24, 2019

Sand Dunes Thawing on Mars Sand Dunes Thawing on Mars


What are these strange shapes on Mars? Defrosting sand dunes. As spring dawned on the Northern Hemisphere of Mars, dunes of sand near the pole, as pictured here in late May by ESA's ExoMars Trace Gas Orbiter, began to thaw. The carbon dioxide and water ice actually sublime in the thin atmosphere directly to gas. Thinner regions of ice typically defrost first revealing sand whose darkness soaks in sunlight and accelerates the thaw. The process might even involve sandy jets exploding through the thinning ice. By summer, spots will expand to encompass the entire dunes. The Martian North Pole is ringed by many similar fields of barchan sand dunes, whose strange, smooth arcs are shaped by persistent Martian winds. via NASA https://ift.tt/2kGShLE

Sep 21, 2019

The Tulip in the Swan The Tulip in the Swan


Framing a bright emission region, this telescopic view looks out across a pretty field of stars along the plane of our Milky Way Galaxy, toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula, the reddish glowing cloud of interstellar gas and dust is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101. About 8,000 light-years distant and 70 light-years across the complex and beautiful nebula blossoms near the center of this composite image. Ultraviolet radiation from young energetic O stars at the edge of the Cygnus OB3 association, ionizes the atoms and powers the emission from the Tulip Nebula. via NASA https://ift.tt/32W6jte

Sep 20, 2019

Saturn at Night Saturn at Night


Still bright in planet Earth's night skies, good telescopic views of Saturn and its beautiful rings often make it a star at star parties. But this stunning view of Saturn's rings and night side just isn't possible from telescopes closer to the Sun than the outer planet. They can only bring Saturn's day into view. In fact, this image of Saturn's slender sunlit crescent with night's shadow cast across its broad and complex ring system was captured by the Cassini spacecraft. A robot spacecraft from planet Earth, Cassini called Saturn orbit home for 13 years before it was directed to dive into the atmosphere of the gas giant on September 15, 2017. This magnificent mosaic is composed of frames recorded by Cassini's wide-angle camera only two days before its grand final plunge. Saturn's night will not be seen again until another spaceship from Earth calls. via NASA https://ift.tt/34YOFXw

Sep 18, 2019

Gigantic Jet Lightning over India Gigantic Jet Lightning over India


Yes, but can your lightning bolt do this? While flying from Munich to Singapore earlier this month, an industrious passenger took images of a passing lightning storm and caught something unexpected: gigantic jet lightning. The jet was captured on a single 3.2-second exposure above Bhadrak, India. Although the gigantic jet appears connected to the airplane's wing, it likely started in a more distant thundercloud, and can be seen extending upwards towards Earth's ionosphere. The nature of gigantic jets and their possible association with other types of Transient Luminous Events (TLEs) such as blue jets and red sprites remains an active topic of research. via NASA https://ift.tt/34VMIeP

Sep 15, 2019

A Long Storm System on Saturn A Long Storm System on Saturn


It was one of the largest and longest lived storms ever recorded in our Solar System. First seen in late 2010, the above cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet. The storm was tracked not only from Earth but from up close by the robotic Cassini spacecraft currently orbiting Saturn. Pictured here in false colored infrared in February, orange colors indicate clouds deep in the atmosphere, while light colors highlight clouds higher up. The rings of Saturn are seen nearly edge-on as the thin blue horizontal line. The warped dark bands are the shadows of the rings cast onto the cloud tops by the Sun to the upper left. A source of radio noise from lightning, the intense storm was thought to relate to seasonal changes when spring emerges in the north of Saturn. After raging for over six months, the iconic storm circled the entire planet and then tried to absorb its own tail -- which surprisingly caused it to fade away. via NASA https://ift.tt/2Aiw4aX

Sep 12, 2019

The Iris Nebula in a Field of Dust The Iris Nebula in a Field of Dust


These cosmic dust clouds drift some 1,300 light-years away along the fertile starfields of the constellation Cepheus. The beautiful Iris Nebula, also known as NGC 7023, blossoms at the upper left. Not the only nebula in the sky to evoke the imagery of flowers, its pretty, symmetric form spans about 6 light-years. This nebula's dominant blue color is characteristic of the pervasive dust grains reflecting light from a nearby hot, bluish star. But darker, obscuring dust clouds cover most of the nearly 4 degree wide field of view. At the right is the LDN 1147/1158 complex of Lynds Dark Nebulae. Stars are forming there, still hidden within the dark cloud cores. A search through the sharp image can identify Herbig-Haro objects though, jets of shocked glowing gas emanating from recently formed stars. via NASA https://ift.tt/2LsA53a

Sep 11, 2019

IC 1805: The Heart Nebula IC 1805: The Heart Nebula


What energizes the Heart Nebula? First, the large emission nebula dubbed IC 1805 looks, in whole, like a human heart. The nebula glows brightly in red light emitted by its most prominent element: hydrogen. The red glow and the larger shape are all powered by a small group of stars near the nebula's center. In the center of the Heart Nebula are young stars from the open star cluster Melotte 15 that are eroding away several picturesque dust pillars with their energetic light and winds. The open cluster of stars contains a few bright stars nearly 50 times the mass of our Sun, many dim stars only a fraction of the mass of our Sun, and an absent microquasar that was expelled millions of years ago. The Heart Nebula is located about 7,500 light years away toward the constellation of Cassiopeia. Coincidentally, a small meteor was captured in the foreground during imaging and is visible above the dust pillars. At the top right is the companion Fishhead Nebula. via NASA https://ift.tt/32D3tZU

Sep 10, 2019

Pluto in True Color Pluto in True Color


What color is Pluto, really? It took some effort to figure out. Even given all of the images sent back to Earth when the robotic New Horizons spacecraft sped past Pluto in 2015, processing these multi-spectral frames to approximate what the human eye would see was challenging. The result featured here, released three years after the raw data was acquired by New Horizons, is the highest resolution true color image of Pluto ever taken. Visible in the image is the light-colored, heart-shaped, Tombaugh Regio, with the unexpectedly smooth Sputnik Planitia, made of frozen nitrogen, filling its western lobe. New Horizons found the dwarf-planet to have a surprisingly complex surface composed of many regions having perceptibly different hues. In total, though, Pluto is mostly brown, with much of its muted color originating from small amounts of surface methane energized by ultraviolet light from the Sun. via NASA https://ift.tt/2Aae3vf

Sep 9, 2019

M31: The Andromeda Galaxy M31: The Andromeda Galaxy


How far can you see? The most distant object easily visible to the unaided eye is M31, the great Andromeda Galaxy, over two million light-years away. Without a telescope, even this immense spiral galaxy appears as an unremarkable, faint, nebulous cloud in the constellation Andromeda. But a bright yellow nucleus, dark winding dust lanes, luminous blue spiral arms, and bright red emission nebulas are recorded in this stunning six-hour telescopic digital mosaic of our closest major galactic neighbor. While even casual skygazers are now inspired by the knowledge that there are many distant galaxies like M31, astronomers seriously debated this fundamental concept only 100 years ago. Were these "spiral nebulae" simply outlying gas clouds in our own Milky Way Galaxy or were they "island universes" -- distant galaxies of stars comparable to the Milky Way itself? This question was central to the famous Shapley-Curtis debate of 1920, which was later resolved by observations favoring Andromeda being just like our Milky Way Galaxy -- a conclusion making the rest of the universe much more vast than many had ever imagined. via NASA https://ift.tt/2ZUfUyY

Sep 8, 2019

Perijove 11: Passing Jupiter Perijove 11: Passing Jupiter


Here comes Jupiter! NASA's robotic spacecraft Juno is continuing on its 53-day, highly-elongated orbits around our Solar System's largest planet. The featured video is from perijove 11 in early 2018, the eleventh time Juno has passed near Jupiter since it arrived in mid-2016. This time-lapse, color-enhanced movie covers about four hours and morphs between 36 JunoCam images. The video begins with Jupiter rising as Juno approaches from the north. As Juno reaches its closest view -- from about 3,500 kilometers over Jupiter's cloud tops -- the spacecraft captures the great planet in tremendous detail. Juno passes light zones and dark belt of clouds that circle the planet, as well as numerous swirling circular storms, many of which are larger than hurricanes on Earth. After the perijove, Jupiter recedes into the distance, now displaying the unusual clouds that appear over Jupiter's south. To get desired science data, Juno swoops so close to Jupiter that its instruments are exposed to very high levels of radiation. via NASA https://ift.tt/2I8jgZh

Sep 7, 2019

In Wolf s Cave In Wolf s Cave


The mysterious blue reflection nebula found in catalogs as VdB 152 or Ced 201 really is very faint. It lies at the tip of the long dark nebula Barnard 175 in a dusty complex that has also been called Wolf's Cave. At the center of this deep and widefield telescopic view, the cosmic apparitions are nearly 1,400 light-years away along the northern Milky Way in the royal constellation Cepheus. Near the edge of a large molecular cloud, pockets of interstellar dust in the region block light from background stars or scatter light from the embedded bright star giving the the nebula its characteristic blue color. Ultraviolet light from the star is also thought to cause a dim reddish luminescence in the nebular dust. Though stars do form in molecular clouds, this star seems to have only accidentally wandered into the area, as its measured velocity through space is very different from the cloud's velocity. Another dense, obscuring dark nebula, LDN 1221, is easy to spot at the upper right in the frame, while the more colorful planetary nebula Dengel-Hartl 5 is just below center. Faint reddish emission from an ancient supernova remnant can also be traced (lower right to upper left) against the dust-rich complex in Cepheus. via NASA https://ift.tt/313KwPR

Sep 6, 2019

Recycling Cassiopeia A Recycling Cassiopeia A


Massive stars in our Milky Way Galaxy live spectacular lives. Collapsing from vast cosmic clouds, their nuclear furnaces ignite and create heavy elements in their cores. After a few million years, the enriched material is blasted back into interstellar space where star formation can begin anew. The expanding debris cloud known as Cassiopeia A is an example of this final phase of the stellar life cycle. Light from the explosion which created this supernova remnant would have been first seen in planet Earth's sky about 350 years ago, although it took that light about 11,000 years to reach us. This false-color image, composed of X-ray and optical image data from the Chandra X-ray Observatory and Hubble Space Telescope, shows the still hot filaments and knots in the remnant. It spans about 30 light-years at the estimated distance of Cassiopeia A. High-energy X-ray emission from specific elements has been color coded, silicon in red, sulfur in yellow, calcium in green and iron in purple, to help astronomers explore the recycling of our galaxy's star stuff. Still expanding, the outer blast wave is seen in blue hues. The bright speck near the center is a neutron star, the incredibly dense, collapsed remains of the massive stellar core. via NASA https://ift.tt/2UCmWav

Sep 5, 2019

The Large Cloud of Magellan The Large Cloud of Magellan


The 16th century Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two fuzzy cloud-like objects easily visible to southern hemisphere skygazers are known as the Clouds of Magellan, now understood to be satellite galaxies of our much larger, spiral Milky Way galaxy. About 160,000 light-years distant in the constellation Dorado, the Large Magellanic Cloud (LMC) is seen here in a remarkably deep, colorful, image. Spanning about 15,000 light-years or so, it is the most massive of the Milky Way's satellite galaxies and is the home of the closest supernova in modern times, SN 1987A. The prominent patch below center is 30 Doradus, also known as the magnificent Tarantula Nebula, a giant star-forming region about 1,000 light-years across. via NASA https://ift.tt/2PKTBMt

Sep 3, 2019

Unusual Signal Suggests Neutron Star Destroyed by Black Hole Unusual Signal Suggests Neutron Star Destroyed by Black Hole


What created this unusual explosion? Three weeks ago, gravitational wave detectors in the USA and Europe -- the LIGO and Virgo detectors -- detected a burst of gravitational radiation that had the oscillating pattern expected when a black hole destroys a neutron star. One object in event S190814sv was best fit with a mass greater than five times the mass of the Sun -- making it a good candidate for a black hole, while the other object appeared to have a mass less than three times the mass of the Sun -- making it a good candidate for a neutron star. No similar event had been detected with gravitational waves before. Unfortunately, no light was seen from this explosion, light that might have been triggered by the disrupting neutron star. It is theoretically possible that the lower mass object was also a black hole, even though no clear example of a black hole with such a low mass is known. The featured video was created to illustrate a previously suspected black hole - neutron star collision detected in light in 2005, specifically gamma-rays from the burst GRB 050724. The animated video starts with a foreground neutron star orbiting a black hole surrounded by an accretion disk. The black hole's gravity then shreds the neutron star, creating a jet as debris falls into the black hole. S190814sv will continue to be researched, with clues about the nature of the objects involved possibly coming from future detections of similar systems. via NASA https://ift.tt/2ZFu7DD

Sep 2, 2019

The Moon and Jupiter over the Alps The Moon and Jupiter over the Alps


What are those bright lights in the sky ahead? When hiking a high mountain pass in northern Italy three weeks ago, a conjunction between our Moon and the distant planet Jupiter was visible as both rose together in the southwest after sunset. The picturesque mountains in the distance are Tre Cime di Lavaredo (Three Peaks of Lavaredo), a UNESCO World Heritage Site and three of the best known mountain peaks in Italy, the Dolomites, and the entire Alps. In the foreground on the left is Locatelli Hut, a refuge for tired hikers as it is located over an hour from nearest parking lot. The bright sky object on the upper left is Saturn. The entire scene was captured on a single 8-second exposure. Jupiter and Saturn will remain prominent in the western sky after sunset this month, while the Moon, in its monthly orbit around the Earth, will pass near Jupiter again in about four days. via NASA https://ift.tt/2kiCbrr

Sep 1, 2019

M45: The Pleiades Star Cluster M45: The Pleiades Star Cluster


Have you ever seen the Pleiades star cluster? Even if you have, you probably have never seen it as dusty as this. Perhaps the most famous star cluster on the sky, the bright stars of the Pleiades can be seen without binoculars from even the depths of a light-polluted city. With a long exposure from a dark location, though, the dust cloud surrounding the Pleiades star cluster becomes very evident. The featured exposure took over 12 hours and covers a sky area several times the size of the full moon. Also known as the Seven Sisters and M45, the Pleiades lies about 400 light years away toward the constellation of the Bull (Taurus). A common legend with a modern twist is that one of the brighter stars faded since the cluster was named, leaving only six stars visible to the unaided eye. The actual number of Pleiades stars visible, however, may be more or less than seven, depending on the darkness of the surrounding sky and the clarity of the observer's eyesight. via NASA https://ift.tt/2MOW7ia