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Auto-locating And Identifying Stars
Simply point the SkyScout at any star in the sky and click the "target" button. The SkyScout will instantly tell you what object you are looking at. To locate a star or planet, select the object's name from the menu and follow the directional arrows through the viewfinder. The SkyScout includes entertaining and educational audio and text information, including facts, trivia, history and mythology about our most popular celestial objects......... Posted by: Brooke Permalink Source March 16, 2006, 6:16 PM CT Years of observing combined into best-yet look at Mars canyon A new view of the biggest canyon in the solar system, merging hundreds of photos from NASA's Mars Odyssey orbiter, offers scientists and the public an online resource for exploring the entire canyon in detail.This canyon system on Mars, named Valles Marineris, stretches as far as the distance from California to New York. Steep walls nearly as high as Mount Everest give way to numerous side canyons, possibly carved by water. In places, walls have shed massive landslides spilling far out onto the canyon floor.
Using new Hubble Space Telescope observations, a research team led by Dr. Hal Weaver of the Johns Hopkins University Applied Physics Laboratory and Dr. Alan Stern of Southwest Research Institute has found that Pluto's three moons are essentially the same color - boosting the theory that the Pluto system formed in a single, giant collision.
Low solar elevation on the landscape produces long shadows of several craters reshaped by lava, debris and erosion, and other geological features.
Double Helix Nebula Near Center Of The Milky Way
"We see two intertwining strands wrapped around each other as in a DNA molecule," said Mark Morris, a UCLA professor of physics and astronomy, and lead author. "Nobody has ever seen anything like that before in the cosmic realm. Most nebulae are either spiral galaxies full of stars or formless amorphous conglomerations of dust and gas -- space weather. What we see indicates a high degree of order." The double helix nebula is approximately 300 light years from the enormous black hole at the center of the Milky Way. (The Earth is more than 25,000 light years from the black hole at the galactic center.). The Spitzer Space Telescope, an infrared telescope, is imaging the sky at unprecedented sensitivity and resolution; Spitzer's sensitivity and spatial resolution were mandatory to see the double helix nebula clearly. "We know the galactic center has a strong magnetic field that is highly ordered and that the magnetic field lines are oriented perpendicular to the plane of the galaxy," Morris said. "If you take these magnetic field lines and twist them at their base, that sends what is called a torsional wave up the magnetic field lines......... Posted by: Brooke Permalink Source Life In Space Discovery A Step Closer
Image courtesy of Franklin Institute
While over 100 gaseous Jupiter-sized planets have been discovered in the last decade, and four medium Neptune-sized planets, until now there have been no discoveries of Earth-sized terrestrial planets that could support life. Dr Philip Yock from The University of Auckland's Faculty of Science says the latest find brings the goal of locating an Earth-like planet in the Milky Way a step closer. The astronomers used the gravitational fields of stars as huge, naturally occurring lenses, as originally proposed by Einstein. This technique is called "gravitational microlensing". "The new planet is Neptune-sized and icy, but unlikely to be covered with a layer of gas like Neptune. Instead it may be more akin to a large, chilly version of our own Earth. The scientists were able to deduce this because they showed that the new planet has no Jupiter-like companion. "Ten years ago, such a finding would have been unthinkable. At the time only a handful of Jupiter-like planets had been found, and medium Neptune-sized planets weren't even on the horizon. Competition between the various groups involved in the hunt for an Earth-twin spurs development onwards."........ Posted by: Brooke Permalink Source How Does The Other Side Of Sun Look Like?
Only half of the sun--the near side--is directly observable. The far side always faces away from Earth and is therefore out of view. But the new technology allows anyone with a computer to download images of the entire solar surface--an important advance with practical applications, say researchers, because potentially damaging solar storms that form on the far side now can be detected days, or even weeks, before they wreak havoc on Earth. "Sunspots, solar flares and other active regions on the surface of the sun emit radiation that can interfere with orbiting satellites, telecommunications and power transmission," says Philip Scherrer, research professor in the Stanford Department of Physics. "This new method allows more reliable warning of magnetic storms brewing on the far side that could rotate with the sun and threaten the Earth." It takes about 27 days for the sun to rotate on its axis, so an active region that forms on the far side can remain hidden for up to 13 days, surprising Earth-bound observers when it finally rotates into view. That's what happened in October 2003, when active regions from the back side suddenly appeared on the eastern edge of the sun, spewing X-rays, ultraviolet radiation and high-energy particles into space. "We were not able to make a public prediction about the intensity of that activity, because at the time we could only image about a quarter to a third of the far side," Scherrer says. "The new method allows us to see the entire far side, including the poles."........ Posted by: Brooke Permalink Source Enceladus Is The Source Of Saturn's E-ring
Writing in the journal Science, researchers show how a plume of icy water vapour bursting out of the South Pole of Enceladus replenishes the water particles that make up the E-ring and creates a dynamic water-based atmosphere around the small moon. The E-ring is Saturn's outermost ring and is composed of microscopic particles. It is very diffuse and stretches between the orbit of two of Saturn's moons, Mimas and Titan. Researchers discovered the dynamic atmosphere during three separate fly-bys of Enceladus by the Cassini spacecraft in February, March and July 2005. Cassini Huygens is a joint NASA/ESA mission to study the Saturnian system. The team working on results from the magnetometer instrument were surprised to discover what they believed was an atmosphere on their first fly-by, 1176km from the moon's surface. After a second flyby at 500km confirmed their observations, they persuaded the Cassini Project to take the next flyby much closer to Enceladus in order to investigate further. On this flyby, at 175km, measurements from all the different instruments on the spacecraft confirmed the presence of an atmosphere. Later remote sensing observations of the moon revealed a plume of water vapour coming from the moon's South Pole......... Posted by: Brooke Permalink Source March 12, 2006, 3:58 PM CT Cometary Globule CG4
Permalink Source: Measuring Geysers Of Enceladus
Announced by the Cassini Imaging Science Team in today's issue of Science, the theory is bolstered by measurements from the Cassini Plasma Spectrometer (CAPS), as published in the same issue by a team led by Robert Tokar of Los Alamos National Laboratory. CAPS was partly designed and built at Los Alamos. "During the July 14 close flyby we began getting signatures, far from Enceladus, of water ejection. From the deflections we could measure of the ionized gas in the magnetosphere, it was erupting at 100 kg per second (220 lbs per second), and the data are consistent with measurements from the spacecraft's other instruments. It is actual H20 molecules," said Tokar. Enceladus is a small moon, but highly reflective due to the fresh layer of snow and ice on its surface. Tokar suggests that the icy geysers at the south pole, erupting from a series of cracks, are pumping a continuous flow of water particles into the area above the moon. Much of the material falls back to the surface as snow......... Posted by: Brooke Permalink Potential Liquid Water On Enceladus
We realize that this is a radical conclusion -- that we may have evidence for liquid water within a body so small and so cold," said Dr. Carolyn Porco, Cassini imaging team leader at Space Science Institute, Boulder, Colo. "However, if we are right, we have significantly broadened the diversity of solar system environments where we might possibly have conditions suitable for living organisms." High-resolution Cassini images show icy jets and towering plumes ejecting large quantities of particles at high speed. Researchers examined several models to explain the process. They ruled out the idea that the particles are produced by or blown off the moon's surface by vapor created when warm water ice converts to a gas. Instead, researchers have found evidence for a much more exciting possibility -- the jets might be erupting from near-surface pockets of liquid water above 0 degrees Celsius (32 degrees Fahrenheit), like cold versions of the Old Faithful geyser in Yellowstone. Mission researchers report these and other Enceladus findings in this week's issue of Science......... Posted by: Brooke Permalink Source Planetary Nebula M2-9
Credit: Gemini Observatory/Travis Rector, University of Alaska Anchorage
Source: Gemini Observatory........ Posted by: Brooke Permalink Source |
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Finding supports theory that single collision created ninth planet's three satellites.
This composite image, obtained by the Advanced Moon Imaging Experiment (AMIE) on board ESA's SMART-1 spacecraft, shows a nice scene near the Moon terminator (the line separating lunar day and night).
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