Posted by
Nexus – 23/03/2010
[via APOD]
Ghostly Zodiacal light, featured near the center of this remarkable panorama, is produced as sunlight is scattered by dust in the Solar System’s ecliptic plane.
In the weeks surrounding the March equinox (today at 1732 UT) Zodiacal light is more prominent after sunset in the northern hemisphere, and before sunrise in the south, when the ecliptic makes a steep angle with the horizon.
In the picture, the narrow triangle of Zodiacal light extends above the western horizon and seems to end at the lovely Pleiades star cluster. Arcing above the Pleiades are stars and nebulae along the plane of our Milky Way Galaxy.
Posted by
Nexus – 23/03/2010
[via APOD]
What shapes the remarkable dust tapestry of the nearby Milky Way Galaxy? No one knows for sure. The intricate structures, shown above, were resolved in new detail recently in a wide region of the sky imaged in far infrared light by the European Space Agency’s Planck satellite.
The above image is a digital fusion of three infrared colors: two taken at high resolution by Planck, while the other is an older image taken by the now defunct IRAS satellite. At these colors, the sky is dominated by the faint glow of very cold gas within only 500 light years of Earth.
Posted by
Nexus – 09/03/2010
[via APOD]
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An eerie blue glow and ominous columns of dark dust highlight M78 and other bright reflection nebula in the constellation of Orion.
The dark filamentary dust not only absorbs light, but also reflects the light of several bright blue stars that formed recently in the nebula. Of the two reflection nebulas pictured above, the more famous nebula is M78, in the image center, while NGC 2071 can be seen to its lower left.
Posted by
Nexus – 08/03/2010
[via APOD]
Reddened light from the setting Sun illuminates the cloud banks hugging this snowy, rugged terrain.
Inspiring a moment of quiet contemplation, the sunset scene included a remarkable pillar of light that seemed to connect the clouds in the sky with the mountains below. Known as a Sun pillar, the luminous column was produced by sunlight reflecting from flat, six-sided ice crystals formed high in the cold atmosphere and fluttering toward the ground.
Last Monday, astronomers watched this Sun pillar slowly fade, as the twilight deepened and clearing, dark skies came to Mt. Jelm and the Wyoming Infrared Observatory.
Posted by
Nexus – 05/03/2010
[via APOD]
Click image for full-size picture (1800x1394)
Magnificent spiral galaxy NGC 4565 is viewed edge-on from planet Earth. Also known as the Needle Galaxy for its narrow profile, bright NGC 4565 is a stop on many telescopic tours of the northern sky, in the faint but well-groomed constellation Coma Berenices.
This sharp, colorful image reveals the galaxy’s bulging central core cut by obscuring dust lanes that lace NGC 4565′s thin galactic plane. An assortment of other galaxies is included in the pretty field of view. Neighboring galaxy NGC 4562 is at the upper right. NGC 4565 itself lies about 40 million light-years distant, spanning some 100,000 light-years.
Posted by
Nexus – 21/02/2010
Put a satellite in a circular orbit about 42,000 kilometres from the center of the Earth (36,000 kilometres or so above the surface) and it will orbit once in 24 hours. Because that matches Earth’s rotation period, it is known as a geosynchronous orbit. If that orbit is also in the plane of the equator, the satellite will hang in the sky over a fixed location in a geostationary orbit.
As predicted in the 1940s by futurist Arthur C. Clarke, geostationary orbits are in common use for communication and weather satellites, a scenario now well-known to astroimagers.
Posted by
Nexus – 13/02/2010
[via APOD]
The snow capped Teide volcano is reflected in a pool of water in this nearly symmetric night sky view from the Canary Island Tenerife.
Bright north star Polaris stands above the peak in an exposure that also captures the brilliant trail of a polar orbiting Iridium satellite.
Of course, with the camera fixed to a tripod, the stars themselves produce concentric trails in long exposures, a reflection of the Earth’s rotation around its axis.
Large astronomical observatories also take advantage of the calm Canary Island sky.
Posted by
Nexus – 03/02/2010
[via discovery.com]
Astronomers presenting at the American Astronomical Society (AAS) meeting in Washington D.C. on Jan. 4, have reported the detection of the emission generated by a black hole as it devoured a white dwarf star in the elliptical galaxy NGC 1399.
This may not appear to be a huge deal to begin with — stars being eaten by supermassive black holes in the centers of galaxies have been detected before — but it would appear that this particular white dwarf was ripped apart and then devoured by a mysterious “intermediate-mass” black hole.
Posted by
Nexus – 29/01/2010
[via APOD]
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An asterism is just a recognized pattern of stars that is not one the 88 official constellations. For example, one of the most famous (and largest) asterisms is the Big Dipper within the constellation Ursa Major. But this pretty chain of stars, visible with binoculars towards the long-necked constellation of Camelopardalis, is also a recognized asterism. Known as Kemble’s Cascade, it contains about 20 stars nearly in a row, stretching over five times the width of a full moon.
Posted by
Nexus – 22/01/2010
[via APOD]
Click image for full-size picture (3018x2804)
Galaxies of the NGC 7771 Group are featured in this intriguing skyscape. Some 200 million light-years distant toward the constellation Pegasus, NGC 7771 is the large, edge-on spiral near center, about 75,000 light-years across, with two smaller galaxies just below it. Large spiral NGC 7769 is seen face-on to the right. Galaxies of the NGC 7771 group are interacting, making repeated close passages that will ultimately result in galaxy-galaxy mergers on a cosmic timescale.
