• What causes the surrounding shells in peculiar galaxy Cen A? In 2002 a fascinating image of peculiar galaxy Centaurus A was released, processed to highlight a faint blue arc indicating an ongoing collision with a smaller galaxy. Another interesting feature of Cen A, however, is the surrounding system of shells, better visible here in this recently released wider pan from
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  • Now shining in eastern skies at dawn, bright planets Venus and Jupiter join the Pleiades star cluster in this sea and sky scape, recorded earlier this week near Buenos Aires, Argentina. Venus dominates the scene that includes bright star Aldebaran just below and to the right. The planets are easy to spot for early morning risers, but this sky also
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  • Part of a dark expanse that splits the crowded plane of our Milky Way galaxy, the Aquila Rift arcs through the northern hemisphere’s summer skies near bright star Altair and the Summer Triangle In silhouette against the Milky Way’s faint starlight, its dusty molecular clouds likely contain raw material to form hundreds of thousands of stars and astronomers eagerly search
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  • The glare of Alpha Centauri, one of the brightest stars in planet Earth’s night sky, floods the left side of this southern skyscape. A mere 4.3 light-years distant, Alpha Centauri actually consists of two component stars similar in size to the Sun, locked in a mutual orbit. Much smaller and cooler, a third member of the same star system, Proxima
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  • When stars form, pandemonium reigns. A particularly colorful case is the star forming region Simeis 188 which houses an unusual and bright cloud arc cataloged as NGC 6559. Visible above are red glowing emission nebulas of hydrogen, blue reflection nebulas of dust, dark absorption nebulas of dust, and the stars that formed from them. The first massive stars formed from
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  • What time is it? If the time and day are right, this sundial will tell you: SOLSTICE. Only then will the Sun be located just right for sunlight to stream through openings and spell out the term for the longest and shortest days of the year. And that happened last week and twice each year. The sundial was constructed by
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  • Sometimes, if you wait long enough for a clear and moonless night, the stars will come out with a vengeance. One such occasion occurred earlier this month at the Piton de l’Eau on Reunion Island. In the foreground, surrounded by bushes and trees, lies a water filled volcanic crater serenely reflecting starlight. A careful inspection near the image center will
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  • In December of 1972, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt spent about 75 hours on the Moon in the Taurus-Littrow valley, while colleague Ronald Evans orbited overhead. This sharp image was taken by Cernan as he and Schmitt roamed the valley floor. The image shows Schmitt on the left with the lunar rover at the edge of Shorty
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  • As seen from Frösön island in northern Sweden the Sun did set a day after the summer solstice. From that location below the arctic circle it settled slowly behind the northern horizon. During the sunset’s final minute, this remarkable sequence of 7 images follows the distorted edge of the solar disk as it just disappears against a distant tree line,
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  • Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small, irregular galaxies form stars too. In fact dwarf galaxy IC 2574 shows clear evidence of intense star forming activity in its telltale pinkish regions of glowing hydrogen gas. Just as in spiral galaxies, the turbulent star-forming
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  • Made with narrow and broad band filters, this colorful cosmic snap shot covers a field of view about the size of the full Moon within the boundaries of the constellation Cygnus. It highlights the bright edge of a ring-like nebula traced by the glow of ionized hydrogen and oxygen gas. Embedded in the region’s interstellar clouds of gas and dust,
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  • Today’s solstice, the astronomical beginning of summer in the north, is at 23:09 UT when the Sun reaches the northernmost declination in its yearly trek through planet Earth’s sky. While most in the northern hemisphere will experience the longest day of the year, for some the Sun won’t set at all, still standing just above the horizon at midnight as
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  • What’s left after a star explodes? To help find out, NASA launched the Nuclear Spectroscopic Telescope Array (NuSTAR) satellite into Earth orbit last week. NuSTAR‘s ability to focus hard X-rays emitted from the nuclei of atoms will be used, among other things, to inspect the surroundings of supernova remnants so as to better understand why these supernovas occurred, what types
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  • Why were the statues on Easter Island built? No one is sure. What is sure is that over 800 large stone statues exist there. The Easter Island statues, stand, on the average, over twice as tall as a person and have over 200 times as much mass. Few specifics are known about the history or meaning of the unusual statues,
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  • Why does Jupiter have rings? Jupiter’s rings were discovered in 1979 by the passing Voyager 1 spacecraft, but their origin was a mystery. Data from the Galileo spacecraft that orbited Jupiter from 1995 to 2003 later confirmed that these rings were created by meteoroid impacts on small nearby moons. As a small meteoroid strikes tiny Adrastea, for example, it will
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