Keyword: astronomy

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  • Astronomy Picture of the Day -- Apollo 17: A Stereo View from Lunar Orbit [3D]

    12/13/2012 8:55:00 PM PST · by SunkenCiv · 6 replies
    NASA ^ | December 13, 2012 | (see photo credit)
    Explanation: Get out your red/blue glasses and check out this awesome stereo view of another world. The scene was recorded by Apollo 17 mission commander Eugene Cernan on December 11, 1972, one orbit before descending to land on the Moon. The stereo anaglyph was assembled from two photographs (AS17-147-22465, AS17-147-22466) captured from his vantage point on board the Lunar Module Challenger as he and Dr. Harrison Schmitt flew over Apollo 17's landing site in the Taurus-Littrow Valley. The broad, sunlit face of the mountain dubbed South Massif rises near the center of the frame, above the dark floor of Taurus-Littrow...
  • Astronomy Picture of the Day -- Milky Way Over Quiver Tree Forest

    12/11/2012 9:40:55 PM PST · by SunkenCiv · 8 replies
    NASA ^ | December 12, 2012 | (see photo credit)
    Explanation: In front of a famous background of stars and galaxies lies some of Earth's more unusual trees. Known as quiver trees, they are actually succulent aloe plants that can grow to tree-like proportions. The quiver tree name is derived from the historical usefulness of their hollowed branches as dart holders. Occurring primarily in southern Africa, the trees pictured in the above 16-exposure composite are in Quiver Tree Forest located in southern Namibia. Some of the tallest quiver trees in the park are estimated to be about 300 years old. Behind the trees is light from the small town of...
  • Astronomy Picture of the Day -- NGC 604: Giant Stellar Nursery

    12/11/2012 4:15:16 AM PST · by SunkenCiv · 4 replies
    NASA ^ | December 11, 2012 | (see photo credit)
    Explanation: Stars are sometimes born in the midst of chaos. About 3 million years ago in the nearby galaxy M33, a large cloud of gas spawned dense internal knots which gravitationally collapsed to form stars. NGC 604 was so large, however, it could form enough stars to make a globular cluster. Many young stars from this cloud are visible in the above image from the Hubble Space Telescope, along with what is left of the initial gas cloud. Some stars were so massive they have already evolved and exploded in a supernova. The brightest stars that are left emit light...
  • Astronomy Picture of the Day -- Time-Lapse: A Total Solar Eclipse

    12/10/2012 7:17:29 PM PST · by SunkenCiv · 5 replies
    NASA ^ | December 10, 2012 | (see photo credit)
    Explanation: Have you ever experienced a total eclipse of the Sun? The above time-lapse movie depicts such an eclipse in dramatic detail as visible from Australia last month. As the video begins, a slight dimming of the Sun and the surrounding Earth is barely perceptible. Suddenly, as the Moon moves to cover nearly the entire Sun, darkness sweeps in from the left -- the fully blocked part of the Sun. At totality, only the bright solar corona extends past the edges of the Moon, and darkness surrounds you. Distant horizons are still bright, though, as they are not in the...
  • Astronomy Picture of the Day -- The Astronaut Who Captured a Satellite [from 1984]

    12/08/2012 9:19:40 PM PST · by SunkenCiv · 16 replies
    NASA ^ | December 09, 2012 | (see photo credit)
    Explanation: In 1984, high above the Earth's surface, an astronaut captured a satellite. It was the second satellite captured that mission. Pictured above, astronaut Dale A. Gardner flies free using the Manned Maneuvering Unit and begins to attach a control device dubbed the Stinger to the rotating Westar 6 satellite. Communications satellite Westar 6 had suffered a rocket malfunction that left it unable to reach its intended high geosynchronous orbit. Both the previously caught Palapa B-2 satellite and the Westar 6 satellite were guided into the cargo bay of the Space Shuttle Discovery and returned to Earth. Westar 6 was...
  • Astronomy Picture of the Day -- Baku Moonrise

    12/08/2012 10:58:48 AM PST · by SunkenCiv · 6 replies
    NASA ^ | December 08, 2012 | (see photo credit)
    Explanation: A Full Moon rises in this waterfront scene. Its colorful, watery reflection is joined by harbor lights and a windowed skyscraper's echo of the western horizon just after sunset. The tantalizing image is a composite of frames recorded at 2 minute intervals on November 28 from the Caspian Sea port city of Baku, Azerbaijan. Still, this Full Moon was not really as big or as bright as others, though it might be hard to tell. In fact, November 28's Full Moon was near apogee, making it the smallest Full Moon of 2012. As it rose over the Baku boardwalk...
  • Astronomy Picture of the Day -- Earth at Night

    12/07/2012 9:13:19 PM PST · by SunkenCiv · 35 replies
    NASA ^ | December 07, 2012 | (see photo credit)
    Explanation: This remarkably complete view of Earth at night is a composite of cloud-free, nighttime images. The images were collected during April and October 2012 by the Suomi-NPP satellite from polar orbit about 824 kilometers (512 miles) above the surface using its Visible Infrared Imaging Radiometer Suite (VIIRS). VIIRS offers greatly improved resolution and sensitivity compared to past global nightlight detecting instrumentation on DMSP satellites. It also has advantages compared to cameras on the International Space Station. While the space station passes over the same point on Earth every two or three days, Suomi-NPP passes over the same point twice...
  • Astronomy Picture of the Day -- 47 Tuc Near the Small Magellanic Cloud

    12/05/2012 9:44:29 PM PST · by SunkenCiv · 3 replies
    NASA ^ | December 06, 2012 | (see photo credit)
    Explanation: Globular star cluster 47 Tucanae is a jewel of the southern sky. Also known as NGC 104, it roams the halo of our Milky Way Galaxy along with around 200 other globular star clusters. The second brightest globular cluster (after Omega Centauri) as seen from planet Earth, it lies about 13,000 light-years away and can be spotted naked-eye near the Small Magellanic Cloud (SMC) in the constellation of the Toucan. Of course, the SMC is some 210,000 light-years distant, a satellite galaxy of our Milky Way and not physically close to 47 Tuc. Stars on the outskirts of the...
  • Astronomy Picture of the Day -- Plasma Jets from Radio Galaxy Hercules A

    12/05/2012 9:30:09 PM PST · by SunkenCiv · 19 replies
    NASA ^ | December 05, 2012 | (see photo credit)
    Explanation: Why does this galaxy emit such spectacular jets? No one is sure, but it is likely related to an active supermassive black hole at its center. The galaxy at the image center, Hercules A, appears to be a relatively normal elliptical galaxy in visible light. When imaged in radio waves, however, tremendous plasma jets over one million light years long appear. Detailed analyses indicate that the central galaxy, also known as 3C 348, is actually over 1,000 times more massive than our Milky Way Galaxy, and the central black hole is nearly 1,000 times more massive than the black...
  • Astronomy Picture of the Day -- In the Center of Saturn's North Polar Vortex

    12/04/2012 8:30:49 PM PST · by SunkenCiv · 6 replies
    NASA ^ | December 04, 2012 | (see photo credit)
    Explanation: What's happening at the north pole of Saturn? A vortex of strange and complex swirling clouds. The center of this vortex was imaged in unprecedented detail last week by the robotic Cassini spacecraft orbiting Saturn. These clouds lie at the center of the unusual hexagonal cloud system that surrounds the north pole of Saturn. Saturn's north pole precessed into sunlight just a few years ago, with Cassini taking only infrared images of the shadowed region previously. The above image is raw and unprocessed and is being prepared for release in 2013. Several similar images of the region have recently...
  • Astronomy Picture of the Day -- A Quadruple Lunar Halo Over Spain

    12/02/2012 9:17:35 PM PST · by SunkenCiv · 7 replies
    NASA ^ | December 03, 2012 | (see photo credit)
    Explanation: Sometimes falling ice crystals make the atmosphere into a giant lens causing arcs and halos to appear around the Sun or Moon. This past Saturday night was just such a time near Madrid, Spain, where a winter sky displayed not only a bright Moon but as many as four rare lunar halos. The brightest object, near the top of the above image, is the Moon. Light from the Moon refracts through tumbling hexagonal ice crystals into a 22 degree halo seen surrounding the Moon. Elongating the 22 degree arc horizontally is a circumscribed halo caused by column ice crystals....
  • Astronomy Picture of the Day -- The Gegenschein Over Chile

    12/01/2012 9:56:19 PM PST · by SunkenCiv · 6 replies
    NASA ^ | December 02, 2012 | (see photo credit)
    Explanation: Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for "counter glow") can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles. These dust particles are millimeter sized splinters from asteroids and orbit in the ecliptic plane of the planets. Pictured above from 2008 October is one of the more spectacular pictures of the gegenschein yet taken. Here a deep exposure of an extremely dark sky over Paranal Observatory in...
  • Astronomy Picture of the Day -- Northern Mercury

    12/01/2012 10:10:52 AM PST · by SunkenCiv · 13 replies
    NASA ^ | December 01, 2012 | (see photo credit)
    Explanation: Innermost planet Mercurywould probably not be a good location for an interplanetary winter olympics. But new results based on data from the Mercury orbitingMESSENGER spacecraft indicate that it does have substantial water icein permanently shadowed regions within craters near its north pole. The possibility of ice on Mercury has been entertained for years, inspired by the discovery of radar bright, hence highly reflective, regions near the north pole. Highlighted in yellow in this map based on projected MESSENGER images, radar bright regions are seen to correspond with floors and walls of north polar impact craters. Farther from the pole...
  • Astronomy Picture of the Day -- Clouds in Cygnus

    11/30/2012 7:47:55 PM PST · by SunkenCiv · 5 replies
    NASA ^ | November 30, 2012 | (see photo credit)
    Explanation: Cosmic clouds of gas and dust drift across this magnificent mosaic covering a 12x12 degree field within the high flying constellation Cygnus. The collaborative skyscape, a combination of broad and narrow band image data presented in the Hubble palette, is anchored by bright, hot, supergiant star Deneb, below center near the left edge. Alpha star of Cygnus, Deneb, is the top of the Northern Cross asterism and is seen here next to the dark void known as the Northern Coal Sack. Below Deneb are the recognizable North America and Pelican nebulae (NGC 7000 and IC 5070). Another supergiant star,...
  • Astronomy Picture of the Day — Super Moon vs. Micro Moon

    11/30/2012 7:40:02 PM PST · by SunkenCiv · 8 replies
    NASA ^ | November 29, 2012 | (see photo credit)
    Explanation: Did you see the big, bright, beautiful Full Moon Wednesday night? That was actually a Micro Moon! On that night, the smallest Full Moon of 2012 reached its full phase only about 4 hours before apogee, the most distant point from Earth in the Moon's elliptical orbit. Of course, earlier this year on May 6, a Full Super Moon was near perigee, the closest point in its orbit. The relative apparent size of November 28's Micro Moon (right) is compared to the famous May 6 Super Moon in these two panels, matching telescopic images from Bucharest, Romania. The difference...
  • Astronomy Picture of the Day -- Jupiter and Io

    11/28/2012 6:28:42 PM PST · by SunkenCiv · 24 replies
    NASA ^ | November 28, 2012 | (see photo credit)
    Explanation: On December 3 (UT), Jupiter, the solar system's largest planet, will be at opposition, opposite the Sun in planet Earth's sky, shining brightly and rising as the Sun sets. That configuration results in Jupiter's almost annual closest approach to planet Earth. So, near opposition the gas giant offers earthbound telescopes stunning views of its stormy, banded atmosphere and large Galilean moons. For example, this sharp series was recorded on the night of November 16/17 from the island of Sardinia near Dolianova, Italy. North is up in the images that show off Jupiter's famous Great Red Spot, and planet girdling...
  • Astronomy Picture of the Day -- Bright Jupiter in Taurus

    11/27/2012 3:22:35 AM PST · by SunkenCiv · 4 replies
    NASA ^ | November 27, 2012 | (see photo credit)
    Explanation: That bright star you've recently noticed rising just after sunset isn't a star at all. It's Jupiter, the solar system's ruling gas giant. Bright Jupiter is nearing its December 3rd opposition when it will stand in Taurus, opposite the Sun in planet Earth's sky. Clearly outshining yellowish Aldebaran, alpha star of Taurus, Jupiter is centered in this skyview from November 14th, also featuring the Pleiades and Hyades star clusters, familiar celestial sights as the northern hemisphere winter approaches. Sliding your cursor over the image will label the scene and identify two other solar system worlds approaching their opposition in...
  • Astronomy Picture of the Day -- Wisps of the Veil Nebula

    11/26/2012 7:28:18 PM PST · by SunkenCiv · 9 replies
    NASA ^ | November 26, 2012 | (see photo credit)
    Explanation: Wisps like this are all that remain visible of a Milky Way star. About 9,000 years ago that star exploded in a supernova leaving the Veil Nebula, also known as the Cygnus Loop. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history. Today, the resulting supernova remnant has faded and is now visible only through a small telescope directed toward the constellation of the Swan (Cygnus). The remaining Veil Nebula is physically huge, however, and even though it lies about 1,400...
  • Astronomy Picture of the Day -- Dark Sand Cascades on Mars

    11/26/2012 7:25:19 PM PST · by SunkenCiv · 23 replies
    NASA ^ | November 25, 2012 | (see photo credit)
    Explanation: They might look like trees on Mars, but they're not. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost. The above image was taken in 2008 April near the North Pole of Mars. At that time, dark sand on the interior of Martian sand dunes became more and more visible as the spring Sun melted the lighter carbon dioxide ice. When occurring near the top of a dune, dark sand may cascade down the dune leaving dark surface streaks -- streaks that might appear at first...
  • Astronomy Picture of the Day -- NGC 1365: Majestic Spiral with Supernova

    11/24/2012 4:51:09 AM PST · by SunkenCiv · 16 replies
    NASA ^ | November 24, 2012 | (see photo credit)
    Explanation: Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax galaxy cluster. This sharp color image shows intense star forming regions at the ends of the bar and along the spiral arms, and details of dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming...