October 12, 2006, 7:48 PM CT

Jupiter's Little Red Spot Growing Stronger

The highest wind speeds in Jupiter's Little Red Spot have increased and are now equal to those in its older and larger sibling, the Great Red Spot, as per observations with NASA's Hubble Space Telescope.

The Little Red Spot's winds, now raging up to approximately 400 miles per hour, signal that the storm is growing stronger, as per the NASA-led team that made the Hubble observations. The increased intensity of the storm probably caused it to change color from its original white in late 2005, as per the team.

"No one has ever seen a storm on Jupiter grow stronger and turn red before," said Amy Simon-Miller of NASA's Goddard Space Flight Center, Greenbelt, Md., lead author of a paper describing the new observations appearing in the journal Icarus. "We hope continued observations of the Little Red Spot will shed light on the a number of mysteries of the Great Red Spot, including the composition of its clouds and the chemistry that gives it its red color."

Eventhough it seems small when viewed against Jupiter's vast scale, the Little Red Spot is actually about the size of Earth, and the Great Red Spot is around three Earth diameters across. Both are giant storms in Jupiter's southern hemisphere powered by warm air rising in their centers.

The Little Red Spot is the only survivor among three white-colored storms that merged together. In the 1940s, the three storms were seen forming in a band slightly below the Great Red Spot. In 1998, two of the storms merged into one, which then merged with the third storm in 2000. In 2005, amateur astronomers noticed that this remaining, larger storm was changing color, and it became known as the Little Red Spot after becoming noticeably red in early 2006.........

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October 12, 2006, 4:59 AM CT

Cassini Finds More Rings

Images taken by NASA's Cassini spacecraft, looking in the direction of the Sun, have provided researchers fresh insights into the dynamic nature of the rings and, in particular, the creation of new rings made from tiny particles released from larger bodies.

Cassini findings being presented this week at the Division for Planetary Sciences Meeting of the American Astronomical Society held in Pasadena, Calif. include several new faint ring structures formed by processes acting on and within Saturn's moons and main rings.

A series of unique observations gathered in mid-September by NASA's Saturn-orbiting Cassini spacecraft as it drifted slowly through Saturn's shadow, allowed the entire ring system to be seen from a perspective that highlights microscopic ring particles: in a number of cases, particles only recently released into Saturn orbit. While observing from this locale, Cassini spotted, a single faint new ring, announced previously, in the shared orbit of the moons Janus and Epimetheus.

Researchers are now ecstatic to find even more rings. A second new diffuse but narrow ring is coincident with the orbit of the tiny moon Pallene, also discovered by Cassini's imaging cameras and only 4 kilometers (2.5 miles) across. Curiously, another similar-sized moon called Methone, discovered earlier in the mission in roughly the same region, does not seem to sport a ring.........

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October 10, 2006, 10:05 PM CT

Gems Of Knowledge

By processing vast amounts of data, computers helped astronomers make new discoveries about the universe. Now they're helping banks and other companies learn more about their customers.

As telescopes scan the heavens they generate huge amounts of data. Take the Hubble Space Telescope, for example. It produces about 1,000 gigabytes of data each year - enough to fill more than 200 million pages. Newer telescopes generate even more.

So what does all this data tell us? That's the question PPARC asked researchers at the University of Edinburgh more than 10 years ago.

All and nothing.

The answer is both all and nothing.

Like other scientific instruments, telescopes only give us the basic facts. They report everything they find - the positions of the objects in space, their brightness and more. And they report it all as accurately as they are able.

Unfortunately telescopes don't explain anything. Why are the stars where they are? What makes them move? Which stars are in which galaxy? And why does their brightness change? Telescopes haven't a clue.

To answer questions like these, astronomers have to put the facts together. Patterns in the data give them vital clues about how the universe works. The problem is that there is so much data to look through.........

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October 9, 2006, 9:18 PM CT

Planets Form From Disks Around Stars

The NASA/ESA Hubble Space Telescope, in collaboration with ground-based observatories, has at last confirmed what philosopher Emmanuel Kant and researchers have long predicted: that planets form from debris disks around stars.

More than 200 years ago, the philosopher Emmanuel Kant first proposed that planets are born from disks of dust and gas that swirl around their home stars. Though astronomers have detected more than 200 extrasolar planets and have seen a number of debris disks around young stars, they have yet to observe a planet and a debris disk around the same star. Now, the NASA/ESA Hubble Space Telescope, in collaboration with ground-based observatories, has at last confirmed what Kant and researchers have long predicted: that planets form from debris disks around stars.

The Hubble observations by an international team of astronomers led by G. Fritz Benedict and Barbara E. McArthur of the University of Texas, Austin, USA, show for the first time that a planet is aligned with its star's circumstellar disk of dust and gas. The planet, detected in year 2000, orbits the nearby Sun-like star Epsilon Eridani, located 10.5 light-years from Earth in the constellation Eridanus. The planet's orbit is inclined 30 degrees to Earth, the same angle at which the star's disk is tilted. The results will appear in the recent issue of the Astronomical Journal.........

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October 8, 2006, 6:42 PM CT

Detailed view of Victoria Crater

With stunningly powerful vision, the HiRISE camera on NASA's Mars Reconnaissance Orbiter has taken a remarkable picture that shows the exploration rover Opportunity poised on the rim of Victoria crater on Mars.

The High Resolution Imaging Science Experiment (HiRISE) camera detailed the entire 800-meter (roughly half-mile) Victoria crater and the rover -- down to its rover tracks and shadows -- in a single high-resolution image taken Wednesday (Oct. 3).

Alfred S. McEwen of the University of Arizona Lunar and Planetary Laboratory released portions of the image that show views of the rover and crater at a NASA press conference in Washington, D.C., today. McEwen is principal investigator for HiRISE, which is operated from UA's Lunar and Planetary Laboratory in Tucson.

"We're poised to have a fantastic mission, and we're not even at prime science mission yet," McEwen said at NASA press briefing this morning. "This was our very first attempt to image 'off-nadir' (at an angle as opposed to straight down), and it worked fabulously well," McEwen added. "It's been an exciting week."

The HiRISE images for Victoria crater are available online at http://hiroc.lpl.arizona.edu/images/TRA/TRA_000873_1780/........

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October 6, 2006, 4:53 AM CT

Black Hole Musical: Epic But Off-Key

A gigantic sonic boom generated by a supermassive black hole has been found with NASA's Chandra X-ray Observatory, along with evidence for a cacophony of deep sound.

This discovery was made by using data from the longest X-ray observation ever of M87, a nearby giant elliptical galaxy. M87 is centrally located in the Virgo cluster of galaxies and is known to harbor one of the Universe's most massive black holes.

Researchers detected loops and rings in the hot, X-ray emitting gas that permeates the cluster and surrounds the galaxy. These loops provide evidence for periodic eruptions that occurred near the supermassive black hole, and that generate changes in pressure, or pressure waves, in the cluster gas that manifested themselves as sound.

"We can tell that a number of deep and different sounds have been rumbling through this cluster for most of the lifetime of the Universe," said William Forman of the Harvard-Smithsonian Center for Astrophysics (CfA).

The outbursts in M87, which happen every few million years, prevent the huge reservoir of gas in the cluster from cooling and forming a number of new stars. Without these outbursts and resultant heating, M87 would not be the elliptical galaxy it is today.

"If this black hole wasn't making all of this noise, M87 could have been a completely different type of galaxy," said team member Paul Nulsen, also of the CfA, "possibly a huge spiral galaxy about 30 times brighter than the Milky Way".........

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October 4, 2006, 10:29 PM CT

Sun Was Born In Star Cluster

The death of a massive nearby star billions of years ago offers evidence the sun was born in a star cluster, say astronomers at the University of Illinois at Urbana-Champaign. Rather than being an only child, the sun could have hundreds or thousands of celestial siblings, now dispersed across the heavens.

In a paper accepted for publication in the Astrophysical Journal, astronomy professors Leslie W. Looney and Brian D. Fields, and undergraduate student John J. Tobin take a close look at short-lived radioactive isotopes once present in primitive meteorites. The researchers' conclusions could reshape current theories on how, when and where planets form around stars.

Short-lived radioactive isotopes are created when massive stars end their lives in spectacular explosions called supernovas. Blown outward, bits of this radioactive material mix with nebular gas and dust in the process of condensing into stars and planets.

When the solar system was forming, some of this material hardened into rocks and later fell to Earth as meteorites.

The radioisotopes have long since vanished from meteorites found on Earth, but they left their signatures in daughter species. By examining the abundances of those daughter species, the researchers could calculate how far away the supernova was, in both distance and time.........

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October 1, 2006, 7:10 PM CT

Stellar Birth Control In The Early Universe

An international team of astronomers based at Yale and Leiden University in The Netherlands observed that "old stars" dominated a number of large galaxies in the early universe, raising the new question of why these galaxies progressed into "adulthood" so early in the life of the universe.

Every year only a handful of new stars are born out of the gas that fills the space between the stars in galaxies like the Milky Way. To account for the large number of stars in the Universe today, about 400 billion in the Milky Way alone, it was thought that the "stellar birth rate" must have been much higher in the past.

Surprisingly, in this study appearing in the October 2 issue of Astrophysical Journal, astronomers using the 8.1m Gemini telescope in Chile report that a number of of the largest galaxies in the Universe had a very low stellar birth rate even when the Universe was only about 20 percent of its present age.

"Our new results imply that the stars in a number of large galaxies were born when the Universe was in its infancy, in the first few billion years after the Big Bang," said team leader Mariska Kriek, a PhD student from Leiden University and Yale. "The results confirm what some astronomers had suspected -- galaxies seem to have some method of 'birth control' that is very effective".........

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September 28, 2006, 10:16 PM CT

Watch How Planets Form

With the VISIR instrument on ESO's Very Large Telescope, astronomers have mapped the disc around a star more massive than the Sun. The very extended and flared disc most likely contains enough gas and dust to spawn planets. It appears as a precursor of debris discs such as the one around Vega-like stars and thus provides the rare opportunity to witness the conditions prevailing previous to or during planet formation.

"Planets form in massive, gaseous and dusty proto-planetary discs that surround nascent stars. This process must be rather ubiquitous as more than 200 planets have now been found around stars other than the Sun," said Pierre-Olivier Lagage, from CEA Saclay (France) and leader of the team that carried out the observations. "However, very little is known about these discs, particularly those around stars more massive than the Sun. Such stars are much more luminous and could have a large influence on their disc, possibly quickly destroying the inner part".

The astronomers used the VISIR instrument [1] on ESO's Very Large Telescope to map in the infrared the disc surrounding the young star HD 97048. With an age of a few million years [2], HD 97048 belongs to the Chameleon I dark cloud, a stellar nursery 600 light-years away. The star is 40 times more luminous than our Sun and is 2.5 times as massive.........

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September 26, 2006, 9:23 PM CT

Intelligent Aircraft Flying

The U.S. military depends on small, unmanned aerial vehicles (UAVs) to perform such tasks as serving as "eyes in the sky" for battalion commanders planning maneuvers. While some of these UAVs can be easily carried in a backpack and launched by hand, they typically require a team of trained operators on the ground, and they perform only short-term tasks individually rather than sustained missions in coordinated groups.

MIT researchers, in collaboration with Boeing's advanced research and development arm, Phantom Works, are working to change that.

They have developed a multiple-UAV test platform that could lay the groundwork for an intelligent airborne fleet that requires little human supervision, covers a wide area, and automatically maintains the "health" of its vehicles (for example, vehicles anticipate when they need refueling, and new vehicles launch to replace lost, damaged, or grounded ones).

Aeronautics and Astronautics Professor Jonathan How, who heads the research team, believes it is the first platform to publicly demonstrate sustained, coordinated, autonomous flight with multiple UAVs.

At the Boeing Tech Expo at Hanscom Air Force Base in May, students on the team conducted more than 60 flights on demand with two UAVs. In the MIT Aerospace Controls Laboratory, the research team regularly conducts flights using three to five UAVs, which have achieved complex tasks such according tosistent surveillance of a defined area.........

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