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August 19, 2006, 9:12 PM CT

Stellar Pinwheels At Our Galaxy's Core

Stellar Pinwheels At Our Galaxy's Core
Astronomers have finally learned the identity of a mysterious "Quintuplet Cluster" of stars situated near the supermassive black hole at our galaxy's core: At least two of the objects are not individual stars, but binary pairs that live fast and die young, forming fiery pinwheels as they spin around one another.

A multinational team led by Peter Tuthill of the University of Sydney in Australia, used the extraordinary resolution of the 10-meter telescope at the W.M. Keck Observatory in Hawaii, to determine the nature of the enigmatic objects. They report their findings in the Aug. 18 issue of the journal Science.

Until these observations, scientists had not known whether the extremely red "cocoon" quintuplets were aging stars surrounded by shells of dust, or young stars accompanied by disks of bright gas. Neither hypothesis was convincing, and neither fully explained the enormous light output: Each quintuplet emits 10,000 to 100,000 times as much radiation as the Sun.

The new findings indicate the quintuplets are members of a rare class called "Wolf-Rayet colliding-wind binaries" -- massive, fast-burning star pairs that live only a few million years before exploding in terminal supernovae. By contrast, the Sun is about 5 billion years old and only middle-aged. The pinwheel effect is caused by the way each star's dusty mantle is affected by that of its partner, producing spiral plumes.........

Posted by: Edwin      Permalink         Source

August 14, 2006, 10:00 PM CT

Large and small stars in harmonious coexistence

Large and small stars in harmonious coexistence
The latest photo from the Hubble Space Telescope, presented at the 2006 General Assembly of the International Astronomical Union in Prague this week, shows a star forming region in the Large Magellanic Cloud (LMC).

This image reveals a large number of low-mass infant stars coexisting with young massive stars.........

Posted by: Edwin      Permalink         Source

August 12, 2006, 2:35 PM CT

Art On The Moon

Art On The Moon
The only piece of art on the moon (depending, we suppose, on one's definition of art) is a 3?-tall aluminum sculpture titled "Fallen Astronaut."

It was created by Belgian artist Paul Van Hoeydonck and installed by Apollo 15 astronaut David Scott, along with a plaque bearing the names of the 14 astronauts and cosmonauts who died in the service of space exploration.........

Posted by: Edwin      Permalink         Source

August 9, 2006, 11:59 PM CT

An Oblique Look On The North Lunar Far West

An Oblique Look On The North Lunar Far West An 'oblique' view of the lunar surface towards the limb, around the Mezentsev, Niepce and Merrill craters
This image, taken by the Advanced Moon Imaging Experiment (AMIE) on board ESA's SMART-1 spacecraft, provides an 'oblique' view of the lunar surface towards the limb, around the Mezentsev, Niepce and Merrill craters, on the far side of the Moon.

"This cratered terrain is similar in topography to near-side highlands," says SMART-1 Project scientist Bernard Foing, "while the far-side equator bulge can reach heights of 7 km, and the South Pole Aitken basin has depths down to 8 km".

AMIE obtained this sequence on 16 May 2006. The imaged area is centred at a latitude of 73º North and a longitude of 124º West(or 34 º further than the West limb seen from Earth).

Normally, the SMART-1 spacecraft points the AMIE camera straight down, in the so-called Nadir pointing mode. In this image, AMIE was looking out 'the side window' and pointing towards the horizon, showing all craters in an oblique view. The largest craters shown are Mezentesev, Niepce and Merrill, located on the lunar far side, not visible from the Earth. Mezentsev is an eroded crater 89 kilometres in diameter, while Niepce and Merrill have the same size 57 km.

Mezentsev is named after Yourij Mezentsev, a Soviet engineer (1929 - 1965) who was one of the first people to design rocket launchers. Joseph Niepce was the French inventor of photography (1765 - 1833), while Paul Merrill was an American astronomer (1887 - 1961).........

Posted by: Edwin      Permalink         Source

August 8, 2006, 9:44 PM CT

Learning From Near-impossible Missions

Learning From Near-impossible Missions Artist's impression of Huygens' descent
Projects for space researchers and astronomers taught LogicaCMG a lot about building mission-critical systems. Customers across the world have benefited from this experience.

"Your mission is almost impossible. If you choose to accept it, you'll have to land a small probe on the surface of Titan, Saturn's giant moon".

"We don't know what it's like there - no one has been before. Your mission is to gather data and get it back to Earth. There's only one chance to get it right".

"Oh, and there's one more thing. The spacecraft that will carry the probe to Saturn will take seven years to get to the launch point. The software to control the probe and its instruments must be tested before it leaves".

Perfect delivery.

LogicaCMG is used to briefs like this. The British company has been writing software for tough space missions ever since the European Space Agency was created.

In 1992 LogicaCMG was selected to develop software to control the Huygens probe's descent onto Titan. It also had to operate the scientific instruments and report their findings to mission control.

The probe would be launched on board the Cassini spacecraft in 1997. The descent would happen seven years later after a journey of 1.2 billion kilometres.........

Posted by: Edwin      Permalink         Source

August 7, 2006, 7:40 AM CT

Station Crew to 'Kick It Up a Notch' With Chef

Station Crew to 'Kick It Up a Notch' With Chef
The crew of the International Space Station will indulge next week in the ultimate "take-out" food, a meal delivered by a NASA space shuttle and designed by chef Emeril Lagasse of the Food Network's "Emeril Live." After tasting several of Lagasse's creations, the three-person crew will talk to the chef at 1:30 p.m. EDT Aug. 10 in a special hookup carried live on NASA TV.

Lagasse sent NASA some of his special recipes for potential use in space. After the mandatory testing and processing, five different meals were selected. Emeril's Mardi Gras jambalaya, mashed potatoes with bacon, green beans with garlic, rice pudding and mixed fruit were delivered to the station aboard the shuttle Discovery in July.

The station is home to NASA astronaut Jeff Williams, Russian cosmonaut Pavel Vinogradov and European Space Agency astronaut Thomas Reiter. Station crews commonly live and work in space for six months. "Our research has indicated that quality, appetizing food is important for the health and morale of astronauts during space missions, particularly long ones," said NASA's Vickie Kloeris, who oversees the development and distribution of food on the space station.

Menu options for shuttle and station crews are more extensive than ever before, with about 200 U.S. food items available. Russian food also is available.........

Posted by: Edwin      Permalink         Source

August 3, 2006, 6:49 AM CT

Shockless Future Spacewalkers' Aim

Shockless Future Spacewalkers' Aim Jeff Williams participates in the first session of extravehicular activity performed by the Expedition 13 crew. Image credit: NASA
Space Station crew members Jeff Williams and Thomas Reiter will work to avoid future shocks during a scheduled 6-hour-plus spacewalk Aug. 3.

They also will have a third station crew member for the first time in more than three years. Expedition 13 Commander Pavel Vinogradov will coach them through their prebreathe exercise program and help them suit up for their outing.

The station crew was reduced to two members in May 2003 in the wake of the Columbia accident. Since then, spacewalkers have had to reconfigure station systems before donning their spacesuits without help.

Once the spacewalk begins, Williams and Reiter will be coached through their tasks by Astronaut Steve Bowen. He will act as spacewalk intravehicular officer from the International Space Station Flight Control Room in Houston's Mission Control Center.

The first and longest major task of the spacewalk is installation of the Floating Potential Measurement Unit (FPMU). That device is designed to measure the electrical potential of the station so ways can be verified or devised to minimize arcing hazards as the ISS grows.

Williams, designated lead spacewalker (EV1), will wear the U.S. spacesuit with red stripes. Reiter, EV2, will wear the all-white suit.

They will spend about half an hour setting up equipment after they emerge from the Quest airlock shortly before 10 a.m. EDT. They'll then move with the FPMU to a camera mount near the upper outboard end of the S1 (starboard one) truss. Total time allotted for the installation is 1 hour, 50 minutes.........

Posted by: Edwin      Permalink         Source

August 2, 2006, 6:44 AM CT

15 Billion Kms And Counting

15 Billion Kms And Counting
The Voyager 1 spacecraft set off from the Earth in 1977 and has clocked up quite a few miles since. On 16th August it is due to reach a whopping 100 AU - 14,959,787,069 km or 9,295,573,000 miles - from the Sun. Eventhough 15 billion kilometres is peanuts by the standards of our local stars, that is well beyond all the planets in our Solar System and is the furthest that any artificial object from the Earth has ever been.

Voyager 1 is now heading away from the Sun at a speedy 17 km/s (38,250 mph) through the heliosheath and should pass beyond the heliopause - the point where the wind from the Sun is balanced by the wind from other stars which demarks interstellar space - within the next 10 years. The flight controllers expect that Voyager 1 (and Voyager 2) will still keep returning data up until 2020, so hopefully our first interstellar travellers will then be able to send back some interesting information about the heliopause.

For more information listen to a nice JPL podcast (13.3 MB).........

Posted by: Edwin      Permalink         Source

July 29, 2006, 8:36 PM CT

Insights Into Granicus And Tinjar Valles

Insights Into Granicus And Tinjar Valles
Granicus Valles and Tinjar Valles

For high resolution images See this page

These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA's Mars Express spacecraft, show the regions of Granicus Valles and Tinjar Valles, which may have been formed partly through the action of subsurface water, due to a process known as sapping.

The HRSC obtained these images during orbit 1383 at a ground resolution of approximately 23.7 metres per pixel. The images have been rotated 90 degrees counter-clockwise, so that North is to the left.

They show the regions of Granicus Valles and Tinjar Valles, lying at approximately 26.8 degree North and 135.7 degree East. The northwest-aligned Granicus Valles and Tinjar Valles are part of the Utopia-Planitia region, an area thought to be covered by a layer of lava that flowed from the northwest flanks of Elysium Mons into the Utopia-Planitia Basin.

Today, this once-smooth volcanic plain is incised by channels of variable size and appearance, including Granicus Valles (towards the West) and Tinjar Valles (towards the North).

Both channel systems evolve from a single main channel entering the image scene from southeast (upper right), exhibiting an approximate width of 3 km and extending 300 m below the surrounding terrain at maximum. The impressive sinuous lava channel emanates from the mouth of a radial, a circular drainage area, and runs to the Elysium rise trending into a graben, which is terrain dissected by tectonic deformation.........

Posted by: Edwin      Permalink         Source

July 28, 2006, 9:47 PM CT

Making Clearer Pictures

Making Clearer Pictures
Software makes pictures clearer.

Software helps astronomers see what's hidden in noisy and blurred images of stars and galaxies. Metropolis Data Consultants uses the same techniques to give doctors and the police clearer pictures to work on.

Astronomers use all sorts of telescopes to explore outer space. Some are optical telescopes - bigger and better versions of those you might have at home. Using lenses and mirrors, they make distant objects seem much nearer than they are.

Other telescopes look for radio waves, x-rays and other types of radiation. They give astronomers a different view of the universe - one that deepens their understanding.

But whichever they use, the problem for astronomers is the same. When they're looking at faint objects far out into space, they don't get perfect pictures.

Blur and noise.

To start with, things move. The Earth is rotating, for example, and the satellites that carry telescopes aren't absolutely stationary. Blurring is inevitable.

To make things even worse, some kinds of telescope add noise to the picture. When the image itself is faint, the result is the sort of picture you get when your TV isn't tuned in properly. You can see that something is there but you can't see it clearly.........

Posted by: John      Permalink         Source

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