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Astronomy (General/Chat)

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  • Astronomy Picture of the Day -- Wisps Surrounding the Horsehead Nebula

    09/08/2012 9:16:56 PM PDT · by SunkenCiv · 13 replies
    NASA ^ | September 09, 2012 | (see photo credit)
    Explanation: The famous Horsehead Nebula in Orion is not alone. A deep exposure shows that the dark familiar shaped indentation, visible just below center, is part of a vast complex of absorbing dust and glowing gas. To bring out details of the Horsehead's pasture, amateur astronomers at the Star Shadow Remote Observatory in New Mexico, USA fixed a small telescope on the region for over seven hours filtering out all but a very specific color of red light emitted by hydrogen. They then added the image to a full color frame taken over three hours. The resulting spectacular picture details...
  • Astronomy Picture of the Day -- Cosmic Rays at Voyager 1

    09/08/2012 9:16:52 PM PDT · by SunkenCiv · 13 replies
    NASA ^ | September 08, 2012 | (see photo credit)
    Explanation: Launched on a grand tour of the outer planets in 1977, by good fortune the twin Voyager spacecraft were also headed in the general direction of the Sun's motion relative to nearby stars. Thirty five years later, Voyager 1 appears to be nearing the boundary of the Sun's heliosphere and interstellar space. Of course the heliosphere is the realm of the Sun defined by the influence of the solar wind and the Sun's magnetic field. But how can you tell when your spacecraft crosses the boundary into interstellar space? One clue would be a sudden increase in the detection...
  • Astronomy Picture of the Day -- IC 4628: The Prawn Nebula

    09/06/2012 9:14:16 PM PDT · by SunkenCiv · 7 replies
    NASA ^ | September 07, 2012 | (see photo credit)
    Explanation: South of Antares, in the tail of the nebula-rich constellation Scorpius, lies emission nebula IC 4628. Nearby hot, massive stars, millions of years young, radiate the nebula with invisible ultraviolet light, stripping electrons from atoms. The electrons eventually recombine with the atoms to produce the visible nebular glow, dominated by the red emission of hydrogen. At an estimated distance of 6,000 light-years, the region shown is about 250 light-years across, spanning an area equivalent to four full moons on the sky. The nebula is also cataloged as Gum 56 for Australian astronomer Colin Stanley Gum, but seafood-loving astronomers might...
  • Astronomy Picture of the Day -- Airglow over Italy

    09/06/2012 8:11:43 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | September 06, 2012 | (see photo credit)
    Explanation: In this serene night skyscape, the Milky Way's graceful arc stretches over prominent peaks in the Italian Alps known as Tre Cime di Lavaredo. A 180 degree wide-angle panorama made in four exposures on August 24, the scene does look to the north and the sky is suffused with an eerie greenish light. Still, the subtle glowing bands are not aurorae, but airglow. Unlike aurorae powered by collisions with energetic charged particles and seen at high latitudes, airglow is due to chemiluminescence, the production of light in a chemical reaction, and found around the globe. The chemical energy is...
  • Astronomy Picture of the Day -- Airglow Over Germany

    09/05/2012 3:00:22 PM PDT · by SunkenCiv · 12 replies
    NASA ^ | September 05, 2012 | (see photo credit)
    Explanation: Does air glow? It does, but it is usually hard to see. When conditions are right, however, a faint glow about 90 kilometers up can be observed, most easily with a wide-angle long-duration camera exposure. The same airglow can also frequently be seen looking down -- in pictures taken from Earth orbit -- as a faint arc hovering above the surface. Pictured above between the beige clouds, above the curving Earth, behind the streaking airplane, and in front of the sparkling stars are some green bands of airglow. The glow is predominantly created by the excitation of atoms by...
  • Astronomy Picture of the Day -- Hurricane Paths on Planet Earth

    09/04/2012 4:04:33 AM PDT · by SunkenCiv · 11 replies
    NASA ^ | September 04, 2012 | (see photo credit)
    Explanation: Should you be worried about hurricanes? To find out, it is useful to know where hurricanes have gone in the past. The above Earth map shows the path of every hurricane reported since 1851, Although striking, a growing incompleteness exists in the data the further one looks back in time. The above map graphically indicates that hurricanes -- sometimes called cyclones or typhoons depending on where they form -- usually occur over water, which makes sense since evaporating warm water gives them energy. The map also shows that hurricanes never cross -- or even occur very near -- the...
  • Asteroid #2 down; on to Asteroid #1!

    09/03/2012 11:44:43 PM PDT · by LibWhacker · 18 replies
    Starts With a BANG! ^ | 8/30/12 | Ethan Siegel
    “I have announced this star as a comet, but since it is not accompanied by any nebulosity and, further, since its movement is so slow and rather uniform, it has occurred to me several times that it might be something better than a comet. But I have been careful not to advance this supposition to the public.” -Giuseppe Piazzi, discoverer of Ceres, the first Asteroid Out beyond Mars, but not quite out as far as Jupiter, a collection of thousands of rocky objects, ranging in size from pebbles all the way up to the size of Texas, lies the...
  • Astronomy Picture of the Day -- M45: The Pleiades Star Cluster

    09/03/2012 12:23:54 PM PDT · by SunkenCiv · 35 replies
    NASA ^ | September 03, 2012 | (see photo credit)
    Explanation: Perhaps the most famous star cluster on the sky, the Pleiades can be seen without binoculars from even the depths of a light-polluted city. Also known as the Seven Sisters and M45, the Pleiades is one of the brightest and closest open clusters. The Pleiades contains over 3000 stars, is about 400 light years away, and only 13 light years across. Quite evident in the above photograph are the blue reflection nebulae that surround the brighter cluster stars. Low mass, faint, brown dwarfs have also been found in the Pleiades. (Editors' note: The prominent diffraction spikes are caused by...
  • Astronomy Picture of the Day -- RBSP Night Launch

    09/02/2012 6:05:34 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | September 02, 2012 | (see photo credit)
    Explanation: This graceful arc traces a Delta rocket climbing through Thursday's early morning skies over Cape Canaveral Air Force Station in Florida, USA. Snug inside the rocket's Centaur upper stage were NASA's twin Radiation Belt Storm Probes (RBSP), now in separate orbits within planet Earth's Van Allen radiation belts. Reflected in the Turn Basin from a vantage point about 3 miles from Space Launch Complex 41, the scene was captured in a composite of two exposures. One highlights the dramatic play of launch pad lighting, clouds, and sky. A subsequent 3 minute long exposure records the rocket's fiery trail. While...
  • Blue Stars Confirm Recent Creation

    09/01/2012 7:28:34 PM PDT · by lasereye · 102 replies
    Institute for Creation Research ^ | September 2012 | Jason Lisle, Ph.D.
    Orion is one of the most well-known and easily recognized constellations of the winter sky. The three bright blue stars in Orions belt seem to draw our attention instantly.1 Such stars are a strong confirmation of the biblical timescale. Most stars generate energy by the process of nuclear fusion of hydrogen into helium in the stellar core. This is a very efficient power source. Theoretically, a star like the sun has enough hydrogen in its core to keep it burning for ten billion years. But thats not the case with blue stars. Blue stars are always more massive than the...
  • Astronomy Picture of the Day -- On a Blue Moon

    09/01/2012 2:56:41 PM PDT · by SunkenCiv · 26 replies
    NASA ^ | September 01, 2012 | (see photo credit)
    Explanation: Rising at sunset, the gorgeous Full Moon of August 31 became the second Full Moon in a month. According to modern reckoning, that makes it a Blue Moon. In fact, parts of the Full Moon do look a little blue in this sharp lunar portrait. Taken just hours before the exact full phase in delightfully clear skies over Nottingham, UK, it features eye-catching bright rays extending from the prominent young crater Tycho in the Moon's southern hemisphere. The slightly color enhanced image also brings out subtle shades of blue, a real characteristic of terrain with a high content of...
  • Astronomy Picture of the Day -- Apollo 11 Landing Site Panorama

    08/30/2012 9:18:42 PM PDT · by SunkenCiv · 11 replies
    NASA ^ | August 30, 2012 | (see photo credit)
    Explanation: Have you seen a panorama from another world lately? Assembled from high-resolution scans of the original film frames, this one sweeps across the magnificent desolation of the Apollo 11 landing site on the Moon's Sea of Tranquility. Taken by Neil Armstrong looking out his window of the Eagle Lunar Module, the frame at the far left (AS11-37-5449) is the first picture taken by a person on another world. Toward the south, thruster nozzles can be seen in the foreground on the left, while at the right, the shadow of the Eagle is visible toward the west. For scale, the...
  • Astronomy Picture of the Day -- Halo of the Cat's Eye

    08/30/2012 9:18:44 PM PDT · by SunkenCiv · 5 replies
    NASA ^ | August 31, 2012 | (see photo credit)
    Explanation: The Cat's Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its haunting symmetries are seen in the very central region of this tantalizing image, processed to reveal the enormous but extremely faint halo of gaseous material, about 6 light-years across, which surrounds the brighter, familiar planetary nebula. Made with narrow and broadband data the composite picture shows the remarkably strong extended emission from twice ionized oxygen atoms in blue-green hues and ionized hydrogen and nitrogen in red. Planetary nebulae have long been appreciated as a final phase in the life of a...
  • Space Sugar Discovered Around Sun-Like Star

    08/30/2012 10:16:01 AM PDT · by skinkinthegrass · 14 replies
    Space.com ^ | 29 August 2012 Time: 06:01 AM ET | SPACE.com Staff
    What a sweet cosmic find! Sugar molecules have been found in the gas surrounding a young sun-like star, suggesting that some of the building blocks of life may actually be present even as alien planets are stillforming in the system.
  • Astronomy Picture of the Day -- A Dark Earth with a Red Sprite

    08/29/2012 2:57:57 PM PDT · by SunkenCiv · 3 replies
    NASA ^ | August 29, 2012 | (see photo credit)
    Explanation: There is something very unusual in this picture of the Earth -- can you find it? A fleeting phenomenon once thought to be only a legend has been newly caught if you know just where to look. The above image was taken from the orbiting International Space Station (ISS) in late April and shows familiar ISS solar panels on the far left and part of a robotic arm to the far right. The rarely imaged phenomenon is known as a red sprite and it can be seen, albeit faintly, just over the bright area on the image right. This...
  • Astronomy Picture of the Day -- Colorful Clouds Near Rho Ophiuchi

    08/28/2012 2:52:46 PM PDT · by SunkenCiv · 19 replies
    NASA ^ | August 28, 2012 | (see photo credit)
    Explanation: Why is the sky near Antares and Rho Ophiuchi so colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark. Antares, a red supergiant and one of the brighter stars in the night sky, lights up the yellow-red clouds on the lower center. Rho Ophiuchi lies at the center of the blue nebula near the top. The distant globular cluster M4 is visible just...
  • Footage of Curiositys Descent onto Mars Interpolated to 25 Frames per Second

    08/27/2012 5:30:44 PM PDT · by SWAMPSNIPER · 40 replies
    PETAPIXEL ^ | August 27, 2012 | Michael Zhang
    NASAs Curiosity Rover snapped photographs at 5 frames per second as it descended onto the face of Mars a few weeks ago. The footage that results when the images are combined into a 15 frame per second HD video is pretty amazing, but apparently not amazing enough for a YouTube user named hahahaspam. He spent four straight days taking the 5 fps footage and interpolating it to 25 frames per second. This means that instead of a video showing the choppy landing at 3 times the actual speed, his video shows the landing smoothly and in real time!
  • Astronomy Picture of the Day -- Curiosity on Mars: Mt. Sharp in View

    08/27/2012 3:31:29 PM PDT · by SunkenCiv · 26 replies
    NASA ^ | August 27, 2012 | (see photo credit)
    Explanation: What's that on the horizon? The light peak is Mt. Sharp -- an eventual destination of the Curiosity rover. The above image mosaic was taken from Bradbury Landing, the landing spot of Curiosity, and shows in the foreground the rover's extended robotic arm. Curiosity's is already on the move crossing the intermediate gravel field toward an interesting terrain feature named Glenelg. Curiosity has also already started analyzing its surroundings by zapping a nearby rock with its laser to analyze the chemical composition of the resulting gas plume. If life ever existed on Mars it might well have been here...
  • Astronomy Picture of the Day -- The Cat's Eye Nebula

    08/25/2012 11:40:38 PM PDT · by SunkenCiv · 8 replies
    NASA ^ | August 26, 2012 | (see photo credit)
    Explanation: 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...
  • Space Shuttle Flight 32 (STS-33) Post Flight Presentation

    08/25/2012 4:58:28 PM PDT · by real saxophonist · 2 replies
    video