September 3, 2006, 7:07 AM CT

The Eternal Life of Stardust

A new image from NASA's Spitzer Space Telescope is helping astronomers understand how stardust is recycled in galaxies.

The cosmic portrait shows the Large Magellanic Cloud, a nearby dwarf galaxy named after Ferdinand Magellan, the seafaring explorer who observed the murky object at night during his fleet's historic journey around Earth. Now, nearly 500 years after Magellan's voyage, astronomers are studying Spitzer's view of this galaxy to learn more about the circular journey of stardust, from stars to space and back again.

The Large Magellanic Cloud is like an open book," said Dr. Margaret Meixner of the Space Telescope Science Institute, Baltimore, Md. "We can see the entire lifecycle of matter in a galaxy in this one snapshot." Meixner is lead author of a paper on the findings to appear in the November 2006 issue of the Astronomical Journal.

The vibrant false-color image, a mosaic of approximately 300,000 individual frames, shows a central blue sea of stars amidst lots of colorful, choppy waves of dust. It can be viewed at: http://www.spitzer.caltech.edu/Media/releases/ssc2006-17/ssc2006-17b.shtml.

Space dust is important for making stars, planets and even people. The tiny particles -- flecks of minerals, ices and carbon-rich molecules -- are everywhere in the universe. Developing stars and solar systems are constantly consuming dust, while older stars shed dust back into space, where it will one day provide the ingredients for new generations of stars.........

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September 3, 2006, 6:55 AM CT

Lockheed to Build Orion Crew Vehicle

NASA has selected Lockheed Martin Corp. as the prime contractor to design, develop, and build Orion, America's spacecraft for a new generation of explorers.

The Orion crew capsule will carry astronauts back to the moon and later to Mars. The first flight with astronauts aboard is planned for no later than 2014. Orion's first flight to the moon is planned for no later than 2020.

Lessons from the past are guiding NASA's next step into the future, as the space agency prepares to replace the space shuttle with an Apollo-style vehicle for human explorers.

The vehicle is Orion, named for one of the brightest and most recognizable star formations in the sky. It will be a multi-purpose capsule -- the central member of a family of spacecraft and shuttle-derived launchers that NASA's Constellation Program is developing to carry astronauts back to the moon and later to Mars. The first flight with astronauts aboard is planned for no later than 2014. Orion's first flight to the moon is planned for no later than 2020.

In what amounts to one of the most significant NASA procurements in more than 30 years, two industry teams, Northrop Grumman/Boeing and Lockheed Martin, spent the past 13 months refining concepts, analyzing requirements and sketching designs for Orion. On Thursday, managers of NASA's Exploration Systems Mission Directorate revealed that Lockheed Martin Corp. of Bethesda, Md., has been chosen to build it.........

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August 28, 2006, 9:57 PM CT

Rare high-altitude clouds found on Mars

Planetary researchers have discovered the highest clouds above any planetary surface. They found them above Mars using the SPICAM instrument on board ESA's Mars Express spacecraft. The results are a new piece in the puzzle of how the Martian atmosphere works.

Until now, researchers had been aware only of the clouds that hug the Martian surface and lower reaches of the atmosphere. Thanks to data from the SPICAM Ultraviolet and Infrared Atmospheric Spectrometer onboard Mars Express, a fleeting layer of clouds have been discovered at an altitude between 80 and 100 kilometres. The clouds are most likely composed of carbon dioxide.

SPICAM made the discovery by observing distant stars just before they disappeared behind Mars. By looking at the effects on the starlight as it travelled through the Martian atmosphere, SPICAM built up a picture of the molecules at different altitudes. Each sweep through the atmosphere is called a profile.

The first hints of the new cloud layer came when certain profiles showed that the star dimmed noticeably when it was behind the 90100 kilometre high atmospheric layer. Eventhough this happened in only one percent of the profiles, by the time the team had collected 600 profiles, they were confident that the effect was real.........

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August 27, 2006, 9:17 PM CT

Low Altitude Flying With Coarse Maps

What exactly determines the time of the SMART-1 impact? What causes the uncertainty in the impact time?

The SMART-1 spacecraft is currently expected to impact the Moon's surface on 3 September 2006, at 07:41 CEST (05:41 UT). However, it is also possible that the small satellite hits the Moon on the prior orbit at 02:37 CEST (00:37 UT). Why?.

The time of impact has been determined by orbit predictions following the major thruster manoeuvres performed from 23 June to 2 July 2006 (plus a few trajectory correction manoeuvres performed on 27 and 28 July 2006) - aimed at changing the impact site from the lunar far-side to the lunar near-side, taking into account the Sun-Earth-Moon gravity perturbations. These make the SMART-1 orbit perilune (point of closest approach to the lunar surface) naturally drift down about one kilometre per orbit.

In determining the impact orbit, ESA's spacecraft control experts are also taking into account the tiny perturbations to the trajectory induced by the small hydrazine thrusters to offload the spacecraft reaction wheels, and some slight additional gravity perturbations. An additional slot is also available for a corrective manoeuvre on 1 and 2 September 2006 if needed, to maintain the impact time as planned and allow ground based observations.........

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August 24, 2006, 9:50 PM CT

Microscopic passengers to hitch ride

When space shuttle Atlantis rockets into space later this week, it will take along three kinds of microbes so scientists can study how their genetic responses and their ability to cause disease change.

The 'Microbe' experiment, part of the STS-115 space shuttle mission scheduled for launch Aug. 27, will study three common microorganisms -- Salmonella typhimurium, Pseudomonas aeruginosa and Candida albicans -- that have been identified as potential threats to crew health. Sending these microbes into space will allow scientists to investigate the microbes' genetic adaptation and ability to cause infectious disease in microgravity, and to better understand the astronauts' space environment. The results of this experiment will help NASA scientists evaluate the risks to astronauts on future exploration missions planned to go to the moon and Mars.

"Spaceflight holds tremendous potential for the development of novel therapeutics, vaccines and diagnostics to treat, prevent and control infectious diseases," said Cheryl A. Nickerson, Ph.D., the experiment's principal investigator and a researcher at the Biodesign Institute at Arizona State University, Tempe. "Our Microbe experiment will be the first to investigate the effects of spaceflight on the disease-causing potential and gene expression profiles of disease-causing microbes." NASA Ames Research Center, Moffett Field, Calif., developed the Microbe payload for flight.........

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August 24, 2006, 9:19 PM CT

Smackdown in the Lake of Excellence

The European Space Agency's Smart-1 mission ends on September 3rd 2006. Appropriately for such a successful mission, its final resting place will be an area of the Moon known as the 'Lake of Excellence'. During its 3-year lifespan, Europe's first mission to the Moon has advanced both lunar science and the technology that underpins it.

UK participation in Smart-1 was funded by the Particle Physics and Astronomy Research Council with additional funds from the British National Space Centre. PPARC CEO Professor Keith Mason hailed the mission's success "Smart-1 has been amazingly successful, both in proving new technologies that will help shape how Europe explores space in the future and in dramatically increasing our understanding of the Moon. With Smart-1 UK and European researchers and engineers have made a significant contribution to future international lunar exploration programmes".

Scientific Success

Smart-1's scientific instruments have subjected the Moon to new scrutiny and worked so well that the mission was extended by an additional year. The UK instrument D-CIXS (a demonstrator compact X-ray spectrometer) has obtained mineral maps of the Moon's composition, looking at the distribution of calcium, magnesium, aluminium, silicon and iron. These will help to determine if the Moon was formed from terrestrial debris after a collision or mostly from a planet-sized object that crashed into the Earth.........

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August 24, 2006, 9:10 PM CT

Pluto is not a planet

The "United Nations" of astronomers has announced a new definition of what a planet is, slightly revising the description preferred by an international panel including an MIT professor that was tasked with the challenge.

Members of the International Astronomical Union (IAU) voted on August 24 to define a planet as an object that is in orbit around the sun, is large enough for its own gravity to pull it into a nearly spherical shape, and has cleared the neighborhood around its orbit -- in other words, it has no other large bodies crossing its path.

The third condition was added to the draft definition of a planet submitted to the IAU about a week ago by MIT's Richard Binzel and his colleagues. Binzel, a professor of planetary science in the Department of Earth, Atmospheric and Planetary Sciences, took responsibility for presenting the final version of the resolution at the time of the final vote.

This means that while Pluto will still be considered a planet, it will technically be a dwarf planet because it is smaller than Mercury. It will be joined in that category by Ceres and 2003 UB313 (a temporary name for an object discovered only three years ago). More "dwarf planets" are expected to be announced by the IAU in the coming months and years.

As a result of the new definition, our solar system now contains eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, plus the three dwarf planets led by Pluto.........

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August 23, 2006, 9:18 PM CT

Studying Atoms Linked To Black Holes

Super-hot atoms in space hold the key to an astronomical mystery, and an Ohio State University astronomer is leading an effort to study those atoms here on Earth.

Anil Pradhan, professor of astronomy, and his team have used supercomputers to perform the most precise energy calculations ever made for these atoms and their properties. As a result, astronomers -- in particular, those hunting black holes -- will have a better idea of what they are looking at when they examine faraway space matter using X-ray telescopes.

The results appear in the recent issue of the Journal of Physics B: Atomic, Molecular and Optical Physics. And while the paper's subject matter is highly technical, it tells a story that weaves together atomic physics, Einstein's theory of relativity, cutting-edge astronomical observations, and some of the world's fastest supercomputers.

Astronomers have spied seas of super-hot atoms in plasma form, circling the centers of very bright galaxies, called active galactic nuclei. The plasma is thought to be a telltale sign of a black hole; the black hole itself is invisible, but any material spiraling into it should be very hot, and shine brightly with X-rays.

Before anyone can prove definitively whether active galaxies contain black holes, astronomers need to measure the energy levels of the excited atoms in the plasma very precisely, and match the measurements with what they know about atomic physics.........

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August 22, 2006, 7:00 PM CT

Close-up on Cuvier crater ridge

This high-resolution image, taken by the Advanced Moon Imaging Experiment (AMIE) on board ESA's SMART-1 spacecraft, shows the young crater 'Cuvier C' on the Moon.

Click for high resolution image

AMIE obtained this sequence on 18 March 2006 from a distance of 591 kilometres from the surface, with a ground resolution of 53 metres per pixel. The imaged area is centred at a latitude of 50.1º South and a longitude of 11.2º East, with a field of view of 27 km. The North is on the right of the image.

"This image shows the resolving power of the SMART-1 camera to measure the morphology of rims and craters in order to diagnose impact processes", says SMART-1 Project scientist Bernard Foing, "or to establish the statistics of small craters for lunar chronology studies".

Cuvier C, a crater about 10 kilometres across, is visible in the lower right part of the image. Cuvier C is located at the edge of the larger old crater Cuvier, a crater 77 kilometres in diameter. The upper left quadrant of the image contains the smooth floor of Cuvier, only one fourth of which is visible in this image.

Crater Cuvier was named after the creator of the comparative anatomy, Georges Cuvier, a 19th century French naturalist (1769 - 1832).........

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August 20, 2006, 9:49 PM CT

SMART-1 on the trail of the Moon's beginnings

The D-CIXS instrument on ESA's Moon mission SMART-1 has produced the first detection from orbit of calcium on the lunar surface. By doing this, the instrument has taken a step towards answering the old question: did the Moon form from part of the Earth?

Scientists responsible for the D-CIXS instrument on SMART-1 are also announcing that they have detected aluminium, magnesium and silicon. "We have good maps of iron across the lunar surface. Now we can look forward to making maps of the other elements," says Manuel Grande of the University of Wales, Aberystwyth UK, and D-CIXS' Principal Investigator.

Knowing how to translate the D-CIXS orbital data into 'ground truth' has been helped by a cosmic coincidence. On 9 August 1976, the Russian spacecraft Luna 24 was launched. On 18 August it touched down in a region of the Moon known as Mare Crisium and returned a sample of the lunar soil to Earth.

In January 2005, SMART-1 was high above Mare Crisium when a giant explosion took place on the Sun. Scientists often dread these storms because they can damage spacecraft but, for the scientists responsible for D-CIXS, it was just what they needed.

The D-CIXS instrument depends on X-ray emission from the Sun to excite elements on the lunar surface, which then emit X-rays at characteristic wavelengths. D-CIXS collects these X-ray fingerprints and translates them into the abundance of each chemical element found on the surface of the Moon. Grande and his colleagues could relate the D-CIXS Mare Crisium results to the laboratory analysis of the Russian lunar samples.........

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