Keyword: astronomy

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  • Astronomy Picture of the Day -- A Halo for NGC 6164

    10/27/2012 1:56:18 AM PDT · by SunkenCiv · 5 replies
    NASA ^ | October 27, 2012 | (see photo credit)
    Explanation: Beautiful emission nebula NGC 6164 was created by a rare, hot, luminous O-type star, some 40 times as massive as the Sun. Seen at the center of the cosmic cloud, the star is a mere 3 to 4 million years old. In another three to four million years the massive star will end its life in a supernova explosion. Spanning around 4 light-years, the nebula itself has a bipolar symmetry. That makes it similar in appearance to more familiar planetary nebulae - the gaseous shrouds surrounding dying sun-like stars. Also like many planetary nebulae, NGC 6164 has been found...
  • Astronomy Picture of the Day -- Reflection Nebula vdB1

    10/26/2012 3:44:26 AM PDT · by SunkenCiv · 4 replies
    NASA ^ | October 26, 2012 | (see photo credit)
    Explanation: Every book has a first page and every catalog a first entry. And so this lovely blue cosmic cloud begins the van den Bergh Catalog (vdB) of stars surrounded by reflection nebulae. Interstellar dust clouds reflecting the light of the nearby stars, the nebulae usually appear blue because scattering by the dust grains is more effective at shorter (bluer) wavelengths. The same type of scattering gives planet Earth its blue daytime skies. Van den Bergh's 1966 list contains a total of 158 entries more easily visible from the northern hemisphere, including bright Pleiades cluster stars and other popular targets...
  • Astronomy Picture of the Day -- The Medusa Nebula

    10/25/2012 3:46:19 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | October 25, 2012 | (see photo credit)
    Explanation: Braided, serpentine filaments of glowing gas suggest this nebula's popular name, The Medusa Nebula. Also known as Abell 21, this Medusa is an old planetary nebula some 1,500 light-years away in the constellation Gemini. Like its mythological namesake, the nebula is associated with a dramatic transformation. The planetary nebula phase represents a final stage in the evolution of low mass stars like the sun, as they transform themselves from red giants to hot white dwarf stars and in the process shrug off their outer layers. Ultraviolet radiation from the hot star powers the nebular glow. The Medusa's transforming star...
  • Astronomy Picture of the Day -- NGC 206 and the Star Clouds of Andromeda

    10/24/2012 3:44:36 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | October 24, 2012 | (see photo credit)
    Explanation: The large stellar association cataloged as NGC 206 is nestled within the dusty arms of neighboring spiral galaxy Andromeda (M31), 2.5 million light-years distant. Seen near the center of this gorgeous close-up of the southwestern extent of Andromeda's disk, the bright, blue stars of NGC 206 indicate its youth. Its youngest massive stars are less than 10 million years old. Much larger than the clusters of young stars in the disk of our Milky Way galaxy known as open or galactic clusters, NGC 206 spans about 4,000 light-years. That's comparable in size to the giant stellar nurseries NGC 604...
  • New Images: Scientists Puzzled By Uranus Weather Patterns

    10/23/2012 9:39:04 AM PDT · by Red Badger · 29 replies
    www.redorbit.com ^ | 10-21-2012 | Staff
    New, exquisitely detailed, high-resolution images of Uranus show off its complex weather patterns and new features of the planet that scientists can’t explain yet. Uranus, the seventh planet from the Sun, is an ice giant composed mainly of frozen methane, water, ammonia and hydrocarbons. In 1986, Voyager 2 passed by Uranus and returned the iconic image that most associate with the planet. This image showed a smooth, blue-green featureless world. This newest image reveals something different, a world swept with intricate cloudy bands, much like Jupiter and Saturn. Uranus is at such a distance from Earth that most telescopes can’t...
  • Astronomy Picture of the Day -- Mammatus Clouds Over Saskatchewan

    10/23/2012 3:11:51 AM PDT · by SunkenCiv · 17 replies
    NASA ^ | October 23, 2012 | (see photo credit)
    Explanation: Normal cloud bottoms are flat. This is because moist warm air that rises and cools will condense into water droplets at a specific temperature, which usually corresponds to a very specific height. As water droplets grow, an opaque cloud forms. Under some conditions, however, cloud pockets can develop that contain large droplets of water or ice that fall into clear air as they evaporate. Such pockets may occur in turbulent air near a thunderstorm. Resulting mammatus clouds can appear especially dramatic if sunlit from the side. These mammatus clouds were photographed over Regina, Saskatchewan, Canada during the past summer....
  • Astronomy Picture of the Day -- A Space Shuttle on the Streets of Los Angeles

    10/22/2012 3:08:19 AM PDT · by SunkenCiv · 7 replies
    NASA ^ | October 22, 2012 | (see photo credit)
    Explanation: Was that the space shuttle that just went by? Garnering attention that could make even a movie star blush, thousands of people watched in awe as a quintessential icon of the space age was towed through the streets of Los Angeles. After landing at LAX airport late last month, the shuttle Endeavour was carefully loaded onto rolling trailers and maneuvered down roads and across bridges to the California Science Center, 20 kilometers away. To many, there was a majesty to the voyage that was beyond description, inspiring people to line the LA streets and wait at windows and balconies...
  • Astronomy Picture of the Day -- The Horsehead Nebula

    10/22/2012 3:05:53 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | October 21, 2012 | (see photo credit)
    Explanation: One of the most identifiable nebulae in the sky, the Horsehead Nebula in Orion, is part of a large, dark, molecular cloud. Also known as Barnard 33, the unusual shape was first discovered on a photographic plate in the late 1800s. The red glow originates from hydrogen gas predominantly behind the nebula, ionized by the nearby bright star Sigma Orionis. The darkness of the Horsehead is caused mostly by thick dust, although the lower part of the Horsehead's neck casts a shadow to the left. Streams of gas leaving the nebula are funneled by a strong magnetic field. Bright...
  • Astronomy Picture of the Day -- Zodiacal Light and Milky Way

    10/21/2012 6:20:33 AM PDT · by SunkenCiv · 9 replies
    NASA ^ | October 20, 2012 | (see photo credit)
    Explanation: Ghostly apparitions of two fundamental planes in planet Earth's sky span this October all-sky view. The scene was captured from a lakeside campsite under dark skies in northern Maine, USA. In it, the plane of our Milky Way Galaxy arcs above faint airglow along the horizon. Zodiacal light, a band of dust scattering sunlight along the solar system's ecliptic plane, stretches almost horizontally across the wide field and intersects the Milky way near a point marked by bright planet Jupiter. Right of Jupiter, past the Pleiades star cluster, is the brightening of the Zodiacal band known as the Gegenschein,...
  • Astronomy Picture of the Day -- Merging NGC 2623

    10/19/2012 5:29:22 PM PDT · by SunkenCiv · 25 replies
    NASA ^ | October 19, 2012 | (see photo credit)
    Explanation: NGC 2623 is really two galaxies that are becoming one. Seen to be in the final stages of a titanic galaxy merger, the pair lies some 300 million light-years distant toward the constellation Cancer. The violent encounter between two galaxies that may have been similar to the Milky Way has produced widespread star formation near a luminous core and along eye-catching tidal tails. Filled with dust, gas, and young blue star clusters, the opposing tidal tails extend well over 50,000 light-years from the merged nucleus. Likely triggered by the merger, accretion by a supermassive black hole drives activity within...
  • Astronomy Picture of the Day -- A View from Next Door

    10/18/2012 8:09:48 PM PDT · by SunkenCiv · 16 replies
    NASA ^ | October 18, 2012 | (see photo credit)
    Explanation: Located just next door, Alpha Centauri is the closest star system to the Sun. A view from our interstellar neighbor a mere 4.3 light-years away is shown in this illustration. The Sun is at the upper right, a bright star against the background of the Milky Way. The crescent in the foreground is an artist's rendering of a planet now reported orbiting Alpha Centauri B, making it the closest known exoplanet. Discovered by astronomer Xavier Dumusque et al. using the planet hunting HARPS instrument to measure minute shifts in the star's spectrum for more than four years, the planet...
  • Planet Found in Nearest Star System to Earth

    10/17/2012 4:46:35 PM PDT · by VanShuyten · 19 replies
    European astronomers have discovered a planet with about the mass of the Earth orbiting a star in the Alpha Centauri system — the nearest to Earth. It is also the lightest exoplanet ever discovered around a star like the Sun. The planet was detected using the HARPS instrument on the 3.6-metre telescope at ESO’s La Silla Observatory in Chile. The results will appear online in the journal Nature on 17 October 2012.
  • Astronomy Picture of the Day -- Aurora Over White Dome Geyser

    10/17/2012 3:36:39 AM PDT · by SunkenCiv · 3 replies
    NASA ^ | October 17, 2012 | (see photo credit)
    Explanation: Sometimes both heaven and Earth erupt. Colorful aurorae erupted unexpectedly earlier this month, with green aurora appearing near the horizon and brilliant bands of red aurora blooming high overhead. A bright Moon lit the foreground of this picturesque scene, while familiar stars could be seen far in the distance. With planning, the careful astrophotographer shot this image mosaic in the field of White Dome Geyser in Yellowstone National Park in the western USA. Sure enough, just after midnight, White Dome erupted -- spraying a stream of water and vapor many meters into the air. Geyser water is heated to...
  • Astronomy Picture of the Day -- A Spiral Nebula Surrounding Star R Sculptoris

    10/16/2012 2:34:08 AM PDT · by SunkenCiv · 12 replies
    NASA ^ | October 16, 2012 | (see photo credit)
    Explanation: What's happening around that star? An unusual spiral structure has been discovered around the Milky Way star R Sculptoris, a red giant star located about 1,500 light years away toward the constellation of the Sculptor (Sculptoris). The star was observed with the new Atacama Large Millimeter/submillimeter Array (ALMA), the most powerful telescopic array observing near millimeter wavelengths, that part of the spectrum situated well beyond red light and between microwaves and radio waves. Data from ALMA observations was used to create a 3D visualization of the gas and dust immediately surrounding the star. A digital slice through this data...
  • Astronomy Picture of the Day -- Black Sun and Inverted Starfield

    10/15/2012 3:52:56 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | October 15, 2012 | (see photo credit)
    Explanation: Does this strange dark ball look somehow familiar? If so, that might be because it is our Sun. In the above image, a detailed solar view was captured originally in a very specific color of red light, then rendered in black and white, and then color inverted. Once complete, the resulting image was added to a starfield, then also color inverted. Visible in the above image of the Sun are long light filaments, dark active regions, prominences peaking around the edge, and a moving carpet of hot gas. The surface of our Sun has become a particularly busy place...
  • Astronomy Picture of the Day -- The Hubble Extreme Deep Field

    10/14/2012 3:04:01 AM PDT · by SunkenCiv · 35 replies
    NASA ^ | October 14, 2012 | (see photo credit)
    Explanation: What did the first galaxies look like? To help answer this question, the Hubble Space Telescope has just finished taking the eXtreme Deep Field (XDF), the deepest image of the universe ever taken in visible light. Pictured above, the XDF shows a sampling of some of the oldest galaxies ever seen, galaxies that formed just after the dark ages, 13 billion years ago, when the universe was only a few percent of its present age. The Hubble Space Telescope's ACS camera and the infrared channel of the WFPC3 camera took the image. Combining efforts spread over 10 years, the...
  • Astronomy Picture of the Day -- Galaxies, Stars, and Dust

    10/12/2012 9:40:32 PM PDT · by SunkenCiv · 10 replies
    NASA ^ | October 13, 2012 | (see photo credit)
    Explanation: Spiky stars and spooky shapes abound in this deep cosmic skyscape. Its well-composed field of view covers about 2 Full Moons on the sky toward the constellation Pegasus. Of course the brighter stars show diffraction spikes, the commonly seen effect of internal supports in reflecting telescopes, and lie well within our own Milky Way galaxy. The faint but pervasive clouds of interstellar dust ride above the galactic plane and dimly reflect the Milky Way's combined starlight. Known as high latitude cirrus or integrated flux nebulae they are associated with molecular clouds. In this case, the diffuse cloud cataloged as...
  • Astronomy Picture of the Day -- Pan-STARRS and Nebulae

    10/12/2012 3:08:20 AM PDT · by SunkenCiv · 2 replies
    NASA ^ | October 12, 2012 | (see photo credit)
    Explanation: A single image from the world's most powerful survey instrument captured this spectacular skyview. Looking toward Sagittarius, the scene spans nearly 3 degrees or six times the width of the Full Moon. At bottom, upper right, and lower left it covers the Lagoon Nebula (M8), the Trifid Nebula (M20), and NGC 6559, in the crowded, dusty starfields of the central Milky Way. The adopted color scheme shows dust reddened starlight in red hues and normally red emission from hydrogen atoms in green. Built and operated by the Pan-STARRS project, the instrument features a 1.4 gigapixel (billion pixel) digital camera...
  • Astronomy Picture of the Day -- Aurorae over Planet Earth

    10/11/2012 4:14:24 AM PDT · by SunkenCiv · 8 replies
    NASA ^ | October 11, 2012 | (see photo credit)
    Explanation: North America at night is easy to recognize in this view of our fair planet from orbit, acquired by the Suomi-NPP satellite on October 8. The spectacular waves of visible light emission rolling above the Canadian provinces of Quebec and Ontario in the upper half of the frame are the Aurora Borealis or northern lights. Encircling the poles and extending to lower latitudes, impressive aurorae seen during the past few days are due to strong geomagnetic storms. The storms were triggered by a solar coronal mass ejection on October 4/5, impacting Earth's magnetosphere some three days later. The curtains...
  • Astronomy Picture of the Day -- Nauset Light Star Trails

    10/10/2012 6:01:53 PM PDT · by SunkenCiv · 8 replies
    NASA ^ | October 10, 2012 | (see photo credit)
    Explanation: In myth, Atlas holds up the heavens, but in this scene they seem to pivot around a lighthouse beacon. Photographed with a camera fixed to a tripod, the well-planned 30 minute exposure records star trails in the northern sky, reflecting the daily rotation of planet Earth. Hidden behind the top of the prominent Nauset Lighthouse on Cape Cod, Massachusetts, USA, the North Celestial Pole is at the center of all the star trail arcs. Making a complete circle, 360 degrees, in 24 hours, the star trail arcs cover 15 degrees each hour or 7.5 degrees in thirty minutes. Foreground...