Astronomy and Stars
Discussions about astronomy and stars. As we look further out what can we find in the universe beyond Earth's atmosphere?
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Until now, the dim, small stars were considered ideal candidates for dark matter. Whatever dark matter is, its gravitational pull ultimately will determine whether the universe will expand forever or will someday collapse. Picking a region in our Milky Way Galaxy, astronomers predicted that Hubble should have spied 38 red dwarf stars if this class of objects harbored most of the dark matter. The diamond-shaped symbols in the left-hand image illustrate what scientists expected to see. Instead, they saw no stars. View the full article
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This series of eight NASA Hubble Space Telescope "snapshots" shows the evolution of the P-Q complex, also called the "gang of four" region, of comet P/Shoemaker-Levy 9. The eight individual frames chronicle changes in the comet during the 12 months before colliding with Jupiter. The sequence shows that the relative separations of the various cometary fragments, thought to range in size from about 500 meters to almost 4 km (2.5 miles) across, changed dramatically over this period. The apparent separation of Q1 and Q2 was only about 1100 kilometers (680 miles) on 1 July 1993 and increased to 28,000 kilometers (17,400 miles) by 20 July 1994. View the full article
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These four NASA Hubble Space Telescope images of Jupiter, as seen in visible (violet) and far-ultraviolet (UV) wavelengths, show the remarkable spreading of the clouds of smoke and dust thrown into the atmosphere after the impacts of the fragments of comet P/Shoemaker-Levy 9. These dark regions provide the only information ever obtained on the wind direction and speed in Jupiter's upper atmosphere. View the full article
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In the Jupiter campaign, scientists wanted to see how the comet collisions affected the Jovian aurorae, rapid and irregular displays of colorful light in a planet's night sky caused by the leakage of charged particles from the magnetosphere into the atmosphere. Following the impacts, some of the resulting debris became electrically charged and traveled along Jupiter's magnetic field lines and created new aurorae in Jupiter's northern hemisphere, as shown in this image. Scientists had never before observed aurorae this far south of where aurorae are typically seen in Jupiter's northern hemisphere. View the full article
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This series of snapshots, taken with NASA's Hubble Space Telescope, shows evolution of the comet P/Shoemaker-Levy 9 impact region called the D/G complex. This feature was produced by two nuclei of comet P/Shoemaker-Levy 9 that collided with Jupiter on 17 and 18 July 1994, respectively, and was later modified again by the impact of the S fragment on 21 July 1994. View the full article
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This series of color-composite maps of Jupiter, assembled from images taken with NASA's Hubble Space Telescope, allows astronomers to trace changes in the dark impact sites that resulted from the July 1994 impact of comet P/Shoemaker-Levy 9 with the giant planet. Through computer image processing, researchers "peel" the atmosphere of Jupiter off its globe and spread it flat into a map. These cylindrical projections show the entire atmosphere of Jupiter in one map. The HST's images show clearly that dark material produced in the comet explosion has continued to spread in Jupiter's atmosphere. However, the "band" of dark material is still clumpy, which suggests that the maj…
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In the weeks following comet P/Shoemaker-Levy 9's spectacular July collision with Jupiter, a team of Hubble telescope astronomers has pored over imaging and spectroscopic data gleaned during the interplanetary bombardment. Their initial findings, combined with results from other space-borne and ground-based telescopes, shed new light on Jupiter's atmospheric winds, its immense magnetic field, the mysterious dark debris from the impacts, and the composition of the doomed comet itself. These four Hubble telescope images of Jupiter, as seen in visible and far-ultraviolet wavelengths, show the remarkable dispersion of the clouds of smoke and dust thrown into the atmosphere …
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Astronomers using NASA's Hubble Space Telescope (HST) have found, to their surprise, that a relatively nearby galaxy harbors a powerful quasar. This active galaxy, known as Cygnus A, is the second strongest radio source in the sky. View the full article
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A natural color NASA Hubble Space Telescope view of the full disk of the giant planet Jupiter shows numerous comet Shoemaker-Levy 9 impact sites as seen on July 22, 1994. View the full article
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Ultraviolet image of Jupiter taken by the Wide Field Camera of the Hubble Space Telescope. The image shows Jupiter's atmosphere at a wavelength of 2550 Angstroms after many impacts by fragments of comet Shoemaker-Levy 9. View the full article
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This is a NASA's Hubble Space Telescope image of the impact sites of fragments "D" and "G" from Comet Shoemaker-Levy 9 which collided with the giant planet Jupiter. The picture has been image processed to correct for the curvature of the disk of Jupiter, so that the spot appears flat, as if the viewer were hovering directly overhead. The large feature was created by the impact of comet fragment "G" which impacted Jupiter on July 18, 1994. The smaller feature to the left was created on July 17, by the impact of comet fragment "D". View the full article
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This series of images, which spans more than five days beginning at 5:33 p.m. EDT on July 16, 1994, was obtained with NASA's Hubble Space Telescope's Wide Field Planetary Camera-2 using the methane filter that reveals details in Jupiter's higher atmosphere. These images show the development of the ejecta from site A, formed by the impact of the first fragment of comet P/Shoemaker-Levy 9. View the full article
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Image of Jupiter with NASA's Hubble Space Telescope's Planetary Camera. Eight impact sights are visible. From left to right are the E/F complex (barely visible on the edge of the planet), the star shaped H site, the impact sites for tiny N, Q1, small Q2, and R, and on the far right limb the D/G complex. The D/G complex also shows extended haze at the edge of the planet. The features are rapidly evolving on timescales of days. The smallest features in the this image are less than 200 kilometers across. This image is a color composite of three filters at 9530, 5500, and 4100 Angstroms. View the full article
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This Hubble telescope image of the giant planet Jupiter reveals the impact sites of two fragments from comet Shoemaker-Levy 9. Twenty-one large chunks of the comet rained down upon Jupiter in July 1994. The impact sites, located in the planet's Southern Hemisphere, are the dark spots in the upper left of the photograph. View the full article
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These images of Jupiter, by NASA's Hubble Space Telescope, reveal the impact sites of fragments "D" and "G" from Comet Shoemaker-Levy 9. The upper right corners of each image points north, showing the impact sites located in Jupiter's southern hemisphere at a latitude of 44 degrees. View the full article
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This comparison of visible light (blue) and far-ultraviolet (FUV) images of Jupiter taken with the Wide Field Planetary Camera-2 (WFPC-2) on NASA's Hubble Space Telescope show how the appearance of the planet and of comet Shoemaker-Levy 9 impact sites differ at these two wavelengths (1400-2100 and 3100-3600 Angstroms). The images taken 20 minutes apart on July 17,1994 (around 19:00 UT), show the impact sites on the southern hemisphere, from left to right, of comet fragments C, A, and E, about 12, 23, and 4 hours after each collision. Jupiter's satellite 10 is seen crossing above the center of the disk, and the famous Great Red Spot is near the eastern limb. View th…
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This NASA Hubble Space Telescope image of Jupiter's cloudtops was taken at 5:32 EDT on July 16, 1994, shortly after the impact of the first fragment (A) of comet Shoemaker-Levy 9. A violet (410 nanometer) filter of the Wide Field Planetary Camera 2 was used to make the image 1.5 hours after the impact. View the full article
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Astronomers at the Space Telescope Science Institute huddle around monitors to get a glimpse of images from fragment A of comet P/Shoemaker-Levy 9's collision with Jupiter in July 1994. View the full article
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Sequence of images showing evidence for a plume near the terminator of Jupiter at the time of comet P/Shoemaker-Levy 9's fragment A impact with Jupiter in July 1994. View the full article
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This is a composite photo, assembled from separate images of Jupiter and cornet P/Shoemaker-Levy 9, as imaged by the Wide Field & Planetary Camera 2 (WFPC2), aboard. NASA's Hubble Space Telescope (HST). View the full article
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Astronomers using the Hubble telescope have uncovered the strongest evidence yet that the planet-making process is common in the Milky Way Galaxy. Observations clearly reveal that great disks of dust – the raw material for planet formation – are swirling around at least half and probably many more of the stars in the Orion Nebula, a star-forming region only 1,500 light-years from Earth. View the full article
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Astronomers using the Hubble telescope have found seemingly conclusive evidence for a massive black hole in the center of the giant elliptical galaxy M87, located 50 million light-years from Earth in the constellation Virgo. Earlier observations suggested that the black hole was present, but they were not decisive. This observation provides very strong support for the existence of gravitationally collapsed objects, which were predicted 80 years ago by Albert Einstein's general theory of relativity. This image shows a spiral-shaped disk of hot gas in the core of M87. Hubble measurements indicate that the disk's rapid rotation is strong evidence that it contains a massive…
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The Hubble telescope has returned valuable new images of supernova 1994I in the inner regions of the "Whirlpool Galaxy," M51, located 20 million light-years from Earth in the constellation Canes Venatici. The arrow marks the supernova's location. The supernova was discovered by amateur astronomers on April 2, 1994 and has been the target of investigations by astronomers using ground-based optical and radio telescopes. At its brightest, around April 10, the supernova was about 100 million times more luminous than the Sun. A supernova is a violent stellar explosion that destroys a massive star. View the full article
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The Hubble telescope has obtained the best images yet of a mysterious mirror-imaged pair of rings of glowing gas encircling the site of the stellar explosion called supernova 1987A. One possibility for these "hula hoops" of gas is that the two rings might be caused by a high-energy beam of radiation that is sweeping across the gas, like a searchlight sweeping across clouds. Though all of the rings appear inclined to our view (so that they appear to intersect), they are probably in three different planes. The small, bright ring lies in a plane containing the supernova; one larger ring lies in front of and the other behind the smallest one. View the full article
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This is a composite HST image taken in visible light showing the temporal evolution of the brightest region of comet P/Shoemaker-Levy 9. In this false-color representation, different shades of red color are used to display different intensities of light. View the full article
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