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Space - The Super Thread

Discussion in 'Politics' started by Halcyon, Apr 27, 2007.

  1. Halcyon Full Member

    Colliding Supernova Remnants
    Credit: Rosa Williams (UIUC Astronomy Department), et al.
    Explanation: When a massive star exhausts its nuclear fuel it explodes. This stellar detonation, a supernova, propels vast amounts of starstuff outwards, initially at millions of miles per hour. For another 100,000 years or so the expanding supernova remnant gradually slows as it sweeps up material and ultimately merges with the gas and dust of interstellar space. Short lived by cosmic standards, these stellar debris clouds are relatively rare and valuable objects for astronomers exploring the life cycles of stars. Yet this double bubble-shaped nebula 160,000 light-years away in the Large Magellanic Cloud may represent something rarer still - the collision of two supernova remnants. This image in the light of excited Hydrogen atoms along with images at X-Ray, radio and other optical wavelengths, suggests that the bubbles are indeed two separate regions of hot gas surrounded by cooler dense shells begining to interact as they expand and make contact.

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  2. Halcyon Full Member

    In the Center of 30 Doradus
    Credit: WFPC2, Hubble Space Telescope, NASA
    Explanation: In the center of 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known. The center of this cluster, known as R136, is boxed in the upper right portion of the above picture. The gas and dust filling the rest of the picture is predominantly ionized hydrogen from the emission nebula 30 Doradus. R136 is composed of thousands of hot blue stars, some about 50 times more massive than our Sun. 30 Doradus and R136 lie in the LMC - a satellite galaxy to our own Milky Way Galaxy. Although the ages of stars in R136 cause it to be best described as an open cluster, R136's density will likely make it a low mass globular cluster in a few billion years.
  3. Halcyon Full Member

    The Brightest Star Yet Known
    Credit: D. F. Figer (UCLA) et al., NICMOS, HST, NASA,
    Explanation: Star light, star bright, a new brightest star has been discovered in the night. This new brightest star is so far away and so obscured by dust, however, that it took the Hubble Space Telescope to confirm it. In 1990 a star named the Pistol Star was known to lie at the center of the Pistol Nebula. In 1995 it was suggested that the Pistol Star was so massive it was throwing off the mass that actually created the Pistol Nebula. Now, observations from the Hubble Space Telescope released today confirm the spectral relation between the star and the nebula. Dramatic implications include that the star emits 10 million times more light than our Sun, and is about 100 times more massive. Astronomers are currently unsure how a star this massive could have formed and how it will act in the future.
  4. Halcyon Full Member

    Mars Pathfinder Super Pan
    Credit: USGS IMP Team, JPL, NASA
    Explanation: Spectacular details of rover tracks, wind-driven soil, and textured rocks on the Martian surface fill this color mosaic. The view is north-northeast from the Sagan Memorial Station at the Pathfinder landing site on Mars. These images are just part of the "Super Panorama" - a detailed color and stereo imaging data set being compiled by Pathfinder's IMP camera. The data set will be used to derive detailed topographic maps of the landing site and to further explore the mineralogy of the martian rocks and soil. The forward rover deployment ramp and the rock named Barnacle Bill, appear in the foreground at the left while the larger Yogi rock is partly visible at the upper right. Criss-crossing tracks were made by the cruising Sojourner robot rover's spiked wheels. With three wheels on each side, the two foot long rover makes tracks about 1.5 feet apart.
  5. Halcyon Full Member

    Ice Clouds over Mars
    Credit: IMP Team, JPL, NASA
    Explanation: Mars has clouds too. The above true color image taken in August by Mars Pathfinder shows clouds of ice high in the Martian atmosphere. Unlike Earth's atmosphere which is composed predominantly of nitrogen and oxygen, Mars' atmosphere is composed mostly of carbon dioxide. Nevertheless, a trace amount of water does freeze into visible clouds at night, which become particularly apparent during the day by reflection of sunlight. Contact was lost with Mars Pathfinder last Sunday but re-established later in the week.

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  6. Halcyon Full Member

    The search for Dark Matter and Dark Energy continues!

    LINK

  7. tourette_ticker Full Member

    A few views of Earth:

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    The colour photograph of Earthrise - taken by Apollo 8 astronaut, William A. Anders, December 24, 1968. Although the photograph is usually mounted with the moon below the earth, this is how Anders saw it.



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    This picture of the Earth and Moon in a single frame, the first of its kind ever taken by a spacecraft, was recorded Sept. 18, 1977, by NASAs Voyager 1 at a distance of 7.25 million miles from Earth. Because Earth is many times brighter than the Moon, the Moon was artificially brightened by a factor of three relative to the Earth by computer enhancement so that both bodies would show clearly in the prints.




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    In the shadow of Saturn, unexpected wonders appear. The robotic Cassini spacecraft now orbiting Saturn recently drifted in giant planet's shadow for about 12 hours and looked back toward the eclipsed Sun. Cassini saw a view unlike any other. First, the night side of Saturn is seen to be partly lit by light reflected from its own majestic ring system. Next, the rings themselves appear dark when silhouetted against Saturn, but quite bright when viewed away from Saturn and slightly scattering sunlight, in the above exaggerated color image. Saturn's rings light up so much that new rings were discovered, although they are hard to see in the above image. Visible in spectacular detail, however, is Saturn's E ring, the ring created by the newly discovered ice-fountains of the moon Enceladus, and the outermost ring visible above. Far in the distance, visible on the image left just above the bright main rings, is the almost ignorable pale blue dot of Earth.
  8. tourette_ticker Full Member

    This photo, made great in combination with Sagan's commentary is my personal favorite earth photos and actually may be my favorite space pic. I may have posted this in this tread already and if so I apologize, but it is worth the rerun... I have read Sagan's words on this dozens of times.

    Sagan himself on the Voyager team pushed for this photo to be taken and his wish was finally granted at nearly 4 billion miles away. On February 14, 1990, NASA commanded the Voyager 1 spacecraft, having completed its primary mission, to turn around to photograph the planets of the Solar System One image Voyager returned was of Earth, showing up as a "pale blue dot" in the grainy photo. Earth seems to be hung in a sunbeam created by glare from the sun on the camera.

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    Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there--on a mote of dust suspended in a sunbeam.

    The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

    Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

    The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

    It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known.

    -- Carl Sagan, Pale Blue Dot, 1994
  9. erik28com Full Member

    I was kind of opposed to a sticky but this really is the perfect thread for SFN politics. Everytime I get annoyed by someone I can just come here and get some perspective.
  10. Halcyon Full Member

    Thanks erik.... I'm glad you're enjoying the thread.


    The Pleiades Star Cluster
    Credit & Copyright: D. Malin (AAO), AATB, ROE, UKS Telescope
    Explanation: It is 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 bright cluster stars. Low mass, faint, brown dwarfs have recently been found in the Pleiades.

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  11. Halcyon Full Member

    Spiral Eddies On Planet Earth
    Credit: STS 41G Crew, NASA
    Explanation: Can you identify this stellar nebula? How many light-years from Earth did you say? Looking like a twisting cloud of gas and dust between the stars this wispy nebulosity is actually close by - a spiral eddy formed near the North Atlantic Gulf Stream off the East coast of the US. Tens of miles across, spiral eddies are an ocean current phenomenon discovered by observations from manned spacecraft. Imaged by the Challenger space shuttle crew during the STS 41G mission this eddy is dramatically visible due to the low sun angle and strong reflection of sunlight. The reflection is caused by a very thin biologically produced oily film on the surface of the swirling water. Prior to STS 41G these eddies were thought to be rare but are now understood to be a significant dynamic feature of ocean currents. However, no good explanation of their origin or persistence exists.

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  12. Halcyon Full Member

    The Butterfly Planetary Nebula
    Credit & Copyright: J. H. Hora & W. B. Latter (U. Hawaii), 2.2-m Telescope, Mauna Kea
    Explanation: As stars age, they throw off their outer layers. Sometimes a highly symmetric gaseous planetary nebula is created, as is the case in M2-9, also called the Butterfly. Most planetary nebulae show this bipolar appearance, although some appear nearly spherical. An unusual characteristic of the Butterfly is that spots on the "wings" appear to have moved slightly over the years. The above picture was taken in three bands of infrared light and computationally shifted into the visible. Much remains unknown about planetary nebulae, including why some appear symmetric, what creates the knots of emission (some known as FLIERS), and how exactly stars create them.

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  13. Halcyon Full Member

    Echos of Supernova 1987A
    Credit: Anglo-Australian Telescope photograph by David Malin
    Copyright: Anglo-Australian Telescope Board
    Explanation: Can you find Supernova 1987a? It's not hard - it occurred in the center of the bulls-eye pattern. Although this stellar detonation was seen more than a decade ago, light from it continues to bounce off nearby interstellar dust and be reflected to us. These two rings are thus echoes of the powerful supernova. As time goes on, these echoes appear to expand outward from the center. The above image was created by subtracting a picture taken before 1987, from a picture taken after.

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  14. Halcyon Full Member

    Moving Echoes Around SN 1987A
    Credit: J. Krist (STScI) et al., WFPC2, HST, NASA
    Explanation: Yesterday's image highlighted reflective rings of light emitted by a supernova explosion. Today's pictures, taken over a year apart, highlight how these echoes are seen to move over time. Visible on the left of each picture is part of a reflective ring, an existing dust cloud momentarily illuminated by the light of Supernova 1987A. Note how the nebulosity reflecting the most light occurs farther to the left in the lower photograph. If you look closely, you can see the actual location of SN 1987A itself on the right of each photograph: it appears in the center of a small yellowish ring. The apparent motion and brightness of these echoes help astronomers understand the abundance and distribution of interstellar nebulae in the LMC galaxy, where the stellar explosion occurred.

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  15. Halcyon Full Member

    Rafting for Solar Neutrinos
    Credit: Super-Kamiokande Collaboration, Japan
    Explanation: Where have all the neutrinos gone? A long time passing since this question was first asked (decades) as increasingly larger and more diverse detectors sensitive to neutrinos from our Sun have found fewer than expected. But why? Above, scientists check the equipment surrounding a huge tank of extremely pure water from the Super-Kamiokande experiment in Japan, designed to detect colliding neutrinos. Large detectors are needed because the neutrino is an elementary particle that goes right through practically everything. Reasons for the lack of solar neutrinos may include a more complex theory for electroweak interactions than currently in use. Future results from detectors like Super-Kamiokande may help us know more.

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  16. Halcyon Full Member

    3-D View Of Jupiter's Clouds
    Credit: Galileo Project, JPL, NASA
    Explanation: Every day is a cloudy day on Jupiter, the Solar System's reigning gas giant. This 3-dimensional visualization presents a simplified model view from between Jovian cloud decks based on imaging and spectral data recorded by the Galileo spacecraft. The separation between the cloud layers and the height variations have been exaggerated. The upper cloud layer is haze a few tens of miles thick. Heights in the lower cloud layers have been color coded; light bluish clouds are high and thin, reddish clouds are low, and white clouds are high and thick. Streaks in the lower layer suggestively lead to a dark blue area, a relatively clear, dry region similar to the site where Galileo's atmospheric probe made the first entry into a gas giant planet's atmosphere on December 7th, 1995.

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  17. Halcyon Full Member

    M31: The Andromeda Galaxy
    Credit & Copyright: Jason Ware
    Explanation: Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it. The several distinct stars that surround Andromeda's image are actually stars in our Galaxy that are well in front of the background object. Andromeda is frequently referred to as M31 since it is the 31st object on Messier's list of diffuse sky objects. M31 is so distant it takes about 2 million years for light to reach us from there. Much about M31 remains unknown, including why the center contains two nuclei.

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  18. Halcyon Full Member

    Irregular Galaxy Sextans A
    Credit: D. Hunter (Lowell Observatory), Z. Levay (STScI)
    Explanation: Grand spiral galaxies often seem to get all the glory. Their newly formed, bright, blue star clusters found along beautiful, symmetric spiral arms are guaranteed to attract attention. But small irregular galaxies form stars too, like this lovely, gumdrop-shaped galaxy, Sextans A. A member of the local group of galaxies which includes the massive spirals Andromeda and our own Milky Way, Sextans A is about 10 million light years distant. The bright Milky Way foreground stars appear yellowish in this view. Beyond them lie the stars of Sextans A with tantalizing young blue clusters clearly visible.

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  19. Halcyon Full Member

    Barringer Crater on Earth
    Credit: D. Roddy (LPI)
    Explanation: What happens when a meteor hits the ground? Usually nothing much, as most meteors are small, and indentations they make are soon eroded away. 49,000 years ago, however, a large meteor created Barringer Meteor Crater in Arizona, pictured above. Barringer is over a kilometer across. In 1920, it was the first feature on Earth to be recognized as an impact crater. Today, over 100 terrestrial impact craters have been identified. Early this morning, the Leonid Meteor Shower reaches its peak, although no impacts of this magnitude are expected.

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  20. Halcyon Full Member

    In the Center of the Trapezium
    Credit: J. Bally, D. Devine, & R. Sutherland, D. Johnson (CITA), HST, NASA
    Explanation: Start with the constellation of Orion. Below Orion's belt is a fuzzy area known as the Great Nebula of Orion or M42. In this nebula is a bright star cluster known as the Trapezium, shown above. New stellar systems are forming there in gigantic globs of gas and dust known as Proplyds. Looking closely at the above picture also reveals that gas and dust surrounding some of the dimmer stars appears to form structures that point away from the brighter stars. The above false color image was made by combining several exposures from the Hubble Space Telescope.

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  21. Halcyon Full Member

    Triton: Neptune's Largest Moon
    Credit: Voyager 2, NASA
    Explanation: On October 10th, 1846, William Lassell was observing the newly discovered planet Neptune. He was attempting to confirm his observation, made just the previous week, that Neptune had a ring. But this time he discovered that Neptune had a satellite as well. Lassell soon proved that the ring was a product of his new telescope's distortion, but the satellite Triton remained. The above picture of Triton was taken in 1989 by the only spacecraft ever to pass Triton: Voyager 2. Voyager 2 found fascinating terrain, a thin atmosphere, and even evidence for ice volcanoes on this world of peculiar orbit and spin. Ironically, Voyager 2 also confirmed the existence of complete thin rings around Neptune - but these would have been quite invisible to Lassell!

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  22. Halcyon Full Member

    Sorry about the pics being so large lately. Mutt is working on the site and disabled the features of being able to attach pictures to a post, so the images we are using are embedded into the post using the IMG tag, and unfortunately they don't scale down to fit your screen, they just stay super huge. I'm trying not to use any VERY large pictures (like panoramas, etc) so that you don't have to scroll like 4-5 pages to the right to see them but until we have the ability to 'attach' pics again, I won't be able to keep them scaled down.

    Thanks to everyone for visiting this thread. I will continue to update it, and thanks to Abba for suggesting it be stickied in this forum.
  23. cecilturtle06 Full Member

  24. Fdubya247 Full Member

    Planet Formation Mystery Solved

    Dave Mosher
    Staff Writer
    SPACE.comWed Aug 29, 1:30 PM ET

    Planet formation is a story with a well-known beginning and end, but how its middle plays out has been an enigma to scientists-until now.

    A new computer-modeled theory shows how rocky boulders around infant stars team up to form planets without falling into stars.

    "This has been a stumbling block for 30 years," said Mordecai-Marc Mac Low, an astrophysicist at the American Museum of Natural History in New York City, of planet formation theories. "The reason is that boulders tend to fall into the star in a celestial blink of an eye. Some mechanism had to be found to prevent them from being dragged into a star."

    The solution: Together, many boulders can join to fight a cosmic headwind that otherwise would doom them.

    Truckin' boulders

    The stuff of rocky planets originates in an accretion disk, or collection of gas and dust that circles around a newborn star. Over time the dust particles bunch together and form large boulders, but eventually they meet "wind" resistance from the disk's mist of gas.

    "They see a headwind. It's deadly and drags them into the star," Mac Low told SPACE.com.

    Modeling the turbulence within the gas, however, showed that boulders can team up and form planets.

    "Turbulence in the disk concentrates boulders in regions of higher pressure," Mac Low said, noting that such a disturbance is enough to enable the boulders to fight the dooming headwind. "If the gas is sped up, the boulders don't see a headwind. By getting the gas going with them they conserve energy and stay in orbit."

    Mac Low compared the effect to a chain of semi-trucks driving down a highway. Each boulder is like a semi-truck "pushing" the gas in front of it, creating a friendly pocket of air behind it that other semis can travel in without using up as much fuel. "The end of the story is that enough boulders gather together, gravity takes over and they collapse into planet-like bodies," Mac Low said..............

    more:
    http://news.yahoo.com/s/space/20070...d&printer=1;_ylt=AoBGW0Nx8VOH7EbxTxR20Z3737YB
  25. artie84

    artie84 Closed by User

    Hubble Ultra Deep Field Image Reveals Galaxies Galore

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    large version > http://i13.tinypic.com/6f9p0ye.jpg

    Galaxies, galaxies everywhere - as far as NASA's Hubble Space Telescope can see. This view of nearly 10,000 galaxies is the deepest visible-light image of the cosmos. Called the Hubble Ultra Deep Field, this galaxy-studded view represents a "deep" core sample of the universe, cutting across billions of light-years.

    The snapshot includes galaxies of various ages, sizes, shapes, and colors. The smallest, reddest galaxies, about 100, may be among the most distant known, existing when the universe was just 800 million years old. The nearest galaxies - the larger, brighter, well-defined spirals and ellipticals - thrived about 1 billion years ago, when the cosmos was 13 billion years old.

    In vibrant contrast to the rich harvest of classic spiral and elliptical galaxies, there is a zoo of oddball galaxies littering the field. Some look like toothpicks; others like links on a bracelet. A few appear to be interacting. These oddball galaxies chronicle a period when the universe was younger and more chaotic. Order and structure were just beginning to emerge.

    The Ultra Deep Field observations, taken by the Advanced Camera for Surveys, represent a narrow, deep view of the cosmos. Peering into the Ultra Deep Field is like looking through an eight-foot-long soda straw.

    In ground-based photographs, the patch of sky in which the galaxies reside (just one-tenth the diameter of the full Moon) is largely empty. Located in the constellation Fornax, the region is so empty that only a handful of stars within the Milky Way galaxy can be seen in the image.

    In this image, blue and green correspond to colors that can be seen by the human eye, such as hot, young, blue stars and the glow of Sun-like stars in the disks of galaxies. Red represents near-infrared light, which is invisible to the human eye, such as the red glow of dust-enshrouded galaxies.

    The image required 800 exposures taken over the course of 400 Hubble orbits around Earth. The total amount of exposure time was 11.3 days, taken between Sept. 24, 2003 and Jan. 16, 2004.

    Object Names: Hubble Ultra Deep Field, HUDF

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