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09/08/2019

Science & Technology - Astronomy picture of the day : Atlas at Dawn

2019 August 9
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Atlas at Dawn 
Image Credit & CopyrightMichael Seeley
Explanation: This single, 251-second long exposure follows the early flight of an Atlas V rocket on August 8, streaking eastward toward the dawn from Cape Canaveral Air Force Station, planet Earth. The launch of the United Launch Alliance rocket was at 6:13am local time. Sunrise was not until 6:48am, but the rocket's downrange plume at altitude is brightly lit by the Sun still just below the eastern horizon. Waters of the Indian River Lagoon in Palm Shores, Forida reflect subtle colors and warming glow of the otherwise calm, predawn sky. The mighty Atlas rocket carried a military communications satellite into Earth orbit. Of course, this weekend the streaks you see in clear skies before the dawn could be Perseid Meteors.

07/08/2019

Science & Technology - Astronomy picture of the day : Jupiter Engulfed and the Milky Way

2019 August 7
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Jupiter Engulfed and the Milky Way 
Image Credit & Copyright: Mohammad S. Hayati
Explanation: This is a good month to see Jupiter. To find our Solar System's largest planet in your sky, look toward the southeast just after sunset -- Jupiter should be the brightest object in that part of the sky. If you have a binoculars or a small telescope, you should be able to see Jupiter's four brightest moons right nearby, and possibly some cloud bands. The featured image was taken about a month ago from the Persian Gulf. The image shows Jupiter just to the right of the nearly vertical band of the central disk of our Milky Way Galaxy. The unnamed rock formations appear in projection like the jaws of a giant monster ready to engulf the Jovian giant. When you see Jupiter, it may be interesting to know that NASA's robotic Juno spacecraft is simultaneously visiting and studying the giant planet. Saturn is also visible this month, and although it is nearby to Jupiter, it is not as bright.

04/08/2019

Science & Technology - Astronomy picture of the day : Rumors of a Dark Universe

2019 August 4
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Rumors of a Dark Universe 
Image Credit: High-Z Supernova Search TeamHSTNASA
Explanation: Twenty-one years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant -- dark energy -- was directly implied by new distant supernova observations. Suggestions of a cosmological constant were not new -- they have existed since the advent of modern relativistic cosmology. Such claims were not usually popular with astronomers, though, because dark energy was so unlike known universe components, because dark energy's abundance appeared limited by other observations, and because less-strange cosmologies without a signficant amount of dark energy had previously done well in explaining the data. What was exceptional here was the seemingly direct and reliable method of the observations and the good reputations of the scientists conducting the investigations. Over the two decades, independent teams of astronomers have continued to accumulate data that appears to confirm the existence of dark energy and the unsettling result of a presently accelerating universe. In 2011, the team leaders wereawarded the Nobel Prize in Physics for their work. The featured picture of a supernova that occurred in 1994 on the outskirts of a spiral galaxy was taken by one of these collaborations.


02/08/2019

Science & Technology - Astronomy picture of the day : Chamaeleon II Dark Cloud

019 August 2
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Chamaeleon II Dark Cloud 
Image Credit & Copyright: Don Goldman
Explanation: A small constellation hiding near the south celestial pole, The Chamaeleon boasts no bright stars. Stars are forming within its constellation boundaries though, in a complex of dark, dusty molecular clouds. Some 500 light-years distant, the Chamaeleon II dark nebula inhabits this view where the cosmic dust clouds standout mostly in silhouette against the starry southern sky. The telescopic frame is about the angular size of a Full Moon and so spans about 5 light-years at the dark cloud's estimated distance. Scattered near center a telltale reddish glow from identified Herbig-Haro objects is seen in the sharp image, jets of shocked glowing gas emanating from recently formed stars.

01/08/2019

Science & Technology - Astronomy picture of the day : Elements in the Aftermath

2019 August 1
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Elements in the Aftermath 
Image Credit: NASA/CXC/SAO
Explanation: Massive stars spend their brief lives furiously burning nuclear fuel. Through fusion at extreme temperatures and densities surrounding the stellar core, nuclei of light elements ike Hydrogen and Helium are combined to heavier elements like Carbon, Oxygen, etc. in a progression which ends with Iron. So a supernova explosion, a massive star's inevitable and spectacular demise, blasts back into space debris enriched in heavier elements to be incorporated into other stars and planets and people). This detailed false-color x-ray image from the orbiting Chandra Observatory shows such a hot, expanding stellar debris cloud about 36 light-years across. Cataloged asG292.0+1.8, this young supernova remnant is about 20,000 light-years distant toward the southern constellation Centaurus. Light from the inital supernova explosion reached Earth an estimated 1,600 years ago. Bluish colors highlight filaments of the mulitmillion degree gas which are exceptionally rich in Oxygen, Neon, and Magnesium. This enriching supernova also produced a pulsar in its aftermath, a rotating neutron star remnant of the collapsed stellar core. The stunning image was released as part of the 20th anniversary celebration of the Chandra X-ray Observatory.

31/07/2019

Science & Technology - Astronomy picture of the day : IC 1795: The Fishhead Nebula

2019 July 31
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IC 1795: The Fishhead Nebula 
Image Credit & Copyright: Alan Pham
Explanation: To some, this nebula looks like the head of a fish. However, this colorful cosmic portrait really features glowing gas and obscuring dust clouds in IC 1795, a star forming region in the northern constellation Cassiopeia. The nebula's colors were created by adopting the Hubble color palette for mapping narrow emission from oxygen, hydrogen, and sulfur atoms to blue, green and red colors, and further blending the data with images of the region recorded through broadband filters. Not far on the sky from the famous Double Star Cluster in Perseus, IC 1795 is itself located next to IC 1805, the Heart Nebula, as part of a complex of star forming regions that lie at the edge of a large molecular cloud. Located just over 6,000 light-years away, the larger star forming complex sprawls along the Perseus spiral arm of our Milky Way Galaxy. At that distance, this picture would span about 70 light-years across IC 1795.

30/07/2019

Science & Technology - Astronomy picture of the day : Star Forming Region NGC 3582 without Stars

2019 July 30
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Star Forming Region NGC 3582 without Stars 
Image Credit & Copyright: Andrew Campbell
Explanation: What's happening in the Statue of Liberty nebula? Bright stars and interesting molecules are forming and being liberated. The complex nebula resides in the star forming region called RCW 57, and besides the iconic monument, to some looks like a flying superhero or a weeping angel. By digitally removing the stars, this image showcases dense knots of dark interstellar dust, fields of glowing hydrogen gas ionized by these stars, and great loops of gas expelled by dying stars. A detailed study of NGC 3576, also known as NGC 3582 and NGC 3584, uncovered at least 33 massive stars in the end stages of formation, and the clear presence of the complex carbon molecules known as polycyclic aromatic hydrocarbons (PAHs). PAHs are thought to be created in the cooling gas of star forming regions, and their development in the Sun's formation nebula five billion years ago may have been an important step in the development of life on Earth.

Music - Video - F. Schubert - Anastasiya Petryshak, Violin : "Ave Maria"

"Ave Maria"
    

29/07/2019

Science & Technology - Astronomy picture of the day : Lightning over the Volcano of Water

2019 July 29
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Lightning over the Volcano of Water 
Image Credit & Copyright: Sergio Montúfar (Pinceladas Nocturnas)
Explanation: Have you ever watched a lightning storm in awe? Join the crowd. Details of what causes lightning are still being researched, but it is known that inside some clouds, internal updrafts cause collisions between ice and snowthat slowly separate charges between cloud tops and bottoms The rapid electrical discharges that are lightning soon result. Lightning usually takes a jagged course, rapidly heating a thin column of air to about three times the surface temperature of the Sun. The resulting shock wave starts supersonically and decays into the loud sound known as thunder. On average, around the world, about 6,000 lightning bolts occur between clouds and the Earth every minute.Pictured earlier this month in a two-image composite, lightning stems from communication antennas near the top of Volcán de Agua (Volcano of Water) in Guatemala.

28/07/2019

Science & Technology - Astronomy picture of the day : The North America Nebula in Infrared

2019 July 28
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The North America Nebula in Infrared 
Image Credit & Copyright: NASAJPL-CaltechL. Rebull (SSC, Caltech); Optical Rollover: DSS, D. De Martin
Explanation: The North America Nebula can do what most North Americans cannot -- form stars. Precisely where in the nebula these stars are forming has been mostly obscured by some of the nebula's thick dust that is opaque to visible light. However, a view of the North America Nebula in infrared light by the orbiting Spitzer Space Telescope has peered through much of the dust and uncovered thousands of newly formed stars. Rolling your cursor over theabove scientifically-colored infrared image will bring up a corresponding optical image of the same region for comparison. The infrared image neatly captures young stars in many stages of formation, from being imbedded in dense knots of gas and dust, to being surrounded by disks and emitted jets, to being clear of their birth cocoons. The North America Nebula (NGC 7000) spans about 50 light years and lies about 1,500 light years away toward the constellation of the Swan (Cygnus). Still, of all the stars known in the North America Nebula, which massive stars emit the energetic light that gives the ionized red glow is still debated.

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