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From: "Moon, Larry J. (JSC-EA411)" <larry.j.moon@nasa.gov>
Date: August 15, 2014 10:05:17 AM CDT
To: "Moon, Larry J. (JSC-EA411)" <larry.j.moon@nasa.gov>
Subject: FW: NASA and Human Spaceflight News - Friday – August 15, 2014
Happy flex Friday everyone and have a safe and great weekend.NASA and Human Spaceflight NewsFriday – August 15, 2014HEADLINES AND LEADSSpecks of star dust likely first from beyond solar systemIrene Klotz – ReutersA NASA spacecraft dispatched 15 years ago to collect samples from a comet also snared what scientists suspect are the first dust specks from interstellar space.Specks Returned From Space May Be Alien VisitorsMarcia Dunn – APThere may be itsy-bitsy aliens among us.Scientists think they have dust specks from outside our solar systemAmina Khan – Los Angeles TimesCall them the seven wonders of interstellar space: Tiny specks of dust captured by a NASA spacecraft may be the first material from outside the solar system ever caught and brought to Earth.NASA Probe May Have Caught Dust from Interstellar Space, a FirstCharles Q. Choi - Space.comSeven tiny grains of rock captured by NASA's comet-chasing Stardust probe in 2004 may be visitors from the vast reaches of interstellar space, researchers say.Stardust team reveals first specks of interstellar dustRachel Ehrenberg – New ScientistCaptured dust grains that flew into our solar system from interstellar space are providing our first on-the-ground glimpse of the stuff between the stars. Having the particles in hand will hopefully shed light on the chemistry of the cosmos.How A Comet-Chasing Spacecraft 'Likely' Brought Interstellar Dust Back To EarthElizabeth Howell – Universe TodayIf the scientists are right, a NASA spacecraft brought stuff from outside the solar system back to Earth. The Stardust spacecraft, which was originally tasked with chasing after Comet Wild 2, brought our planet seven grains that look fluffier than expected.First dust grains from outside the Solar SystemCitizen-science project identifies particles caught by NASA craft as having likely interstellar origin.Nicole Skinner – NatureSeven particles captured by a NASA probe could be the first known samples of interstellar dust to be brought back to Earth.Former NASA Chief: U.S. Not On A Path To MarsMark Carreau - Aviation WeekU.S. policymakers and others passionate about a human Mars landing are delusional if they believe the nation that ended its first foray into deep space with the Apollo moon landings is on a calculated path to the Red Planet, according to former NASA administrator Mike Griffin.Sierra Nevada's space plane in the chase with SpaceX and Boeing to win NASA nodCompany's Dream Chaser orbital glider has yet to achieve orbit but still is a contender to ferry Americans to and from space stationGeoffrey Giller - Scientific AmericanNASA ended its space shuttle program in 2011, in part to focus on other goals such as putting humans in deep space and on Mars. But the agency still needs a reliable and cost-effective way to get astronauts to and from the International Space Station (ISS). For the past several years it has been paying Russia to do just that. But soon, it will no longer have to do so.Shuttle replica makes final landing atop 747 at Space Center Houston200-foot-tall crane was operated by Dutch company Mammoet, based in RosharonHarvey Rice – Houston ChronicleAs hundreds of eager onlookers watched, a crane on Thursday lifted the space shuttle replica Independence nearly three stories high to its resting place atop a Boeing 747 at Space Center Houston, where visitors will eventually be able to tour the attraction.NASA Chief On Past And Future Of U.S. Space ProgramWBUR-FMNASA Administrator Charles Bolden joins Here & Now's Jeremy Hobson for a wide-ranging conversation about the past and future of NASA's effort to explore the universe.Space Station Supply Ship Exits, Now Packing TrashMarcia Dunn – APA commercial cargo ship has ended its monthlong space station visit.COMPLETE STORIESSpecks of star dust likely first from beyond solar systemIrene Klotz – ReutersA NASA spacecraft dispatched 15 years ago to collect samples from a comet also snared what scientists suspect are the first dust specks from interstellar space.The Stardust robotic spacecraft was launched in 1999 to fly by a comet and collect samples from Comet Wild 2 (pronounced "Vilt 2") and parachute them back to Earth in 2006. Before reaching the comet, the spacecraft also twice opened a collection tray to fish for particles that may have come into the solar system from interstellar space.Now, after a Herculean effort involving thousands of volunteer researchers, scientists say they have what they believe are the first seven specks of freshly plucked dust hailing from exploded stars and other cosmic phenomena beyond the solar system.The grains, described in a paper in this week's edition of the journal, Science, are unexpectedly diverse in shape, size and content, indicating that interstellar dust likely has a more complex and varied evolution than originally thought, said lead author Andrew Westphal, a physicist with the University of California Berkeley's Space Science Laboratory.Two of the particles are bigger than the rest, though that is a very relative term when speaking of specks that are about 4 microns, or one-16,000th of an inch (0.0004 cm) across.These two dust grains, which appear fluffy, like snowflakes, contain a magnesium-iron-silicate mineral called olivine, a hint that they may have come from disks around other stars before being altered by interstellar travel, Westphal said.Some of the interstellar grains also may have organics, added space scientist Michael Zolensky, who oversees NASA's collection of extraterrestrial samples at the Johnson Space Center in Houston.Scientists hope to tease out more information from the dust motes, but not quite yet. They say more sophisticated equipment and processes are needed to analyze the tiny samples without destroying them."The prudent thing is just to put these away for a while and then wait until better techniques come along to make the analysis," Zolensky said.In the meantime, the volunteer effort to find other potential interstellar grains in Stardust's collection trays continues. The particles were trapped in a smoke-like substance called aerogel, but their telltale impact tracks are so tiny that scientists had no choice but to recruit volunteers to assist in the search."This takes real effort," Westphal said. "You're not just launching your computer off on a project. You're having to do it yourself."So far, about 30,700 self-described "dusters" have collectively done more than 100 million searches for interstellar dust particles by scanning digitized images of Stardust's translucent aerogel collectors.The next phase of the Stardust@home project starts on Friday.Specks Returned From Space May Be Alien VisitorsMarcia Dunn – APThere may be itsy-bitsy aliens among us.Scientists say seven microscopic particles collected by NASA's comet-chasing spacecraft, Stardust, appear to have originated outside our solar system. If confirmed, this would be the world's first sampling of contemporary interstellar dust."They are very precious particles," the team leader, physicist Andrew Westphal of the University of California, Berkeley, said in a statement Thursday.The dust collectors were exposed to what is believed to be the interstellar dust stream in the early 2000s and returned to Earth in 2006. Since then, dozens of scientists worldwide led by Westphal have examined scans of the collection panels to zero in on the particles. The team was assisted by 30,000 citizen-scientists, dubbed Dusters, who reviewed more than 1 million images in search of elusive tracks made by incoming particles.The findings were published Thursday in the journal Science.Westphal said the suspected interstellar particles are surprisingly diverse. Some are fluffy like snowflakes.A few particles splatted a little when they hit the collection panels because of their speed and the fact that some ended up hitting the aluminum foils between the softer aerogel tiles meant to capture the grains. In fact, one particle believed to be following the flow of interstellar wind was vaporized because it was going so fast — an estimated 10 miles per second.The dust is considered young by cosmic standards: less than 50 million to 100 million years old, the life expectancy of interstellar dust.Westphal said additional testing is needed before concluding these seven specks are truly from outside our solar system. And there may be more: Roughly half the dust-collection panels have yet to be scanned. The physicist expects to find no more than a dozen interstellar dust specks in all, however, a tiny fraction of the amount of comet matter gathered by Stardust.More than 50 grains embedded in the Stardust collectors were deemed to be debris from the spacecraft itself.NASA launched Stardust in 1999 to collect debris from Comet Wild-2. The Stardust capsule parachuted back to Earth, landing in the Utah desert seven years later.Scientists think they have dust specks from outside our solar systemAmina Khan – Los Angeles TimesCall them the seven wonders of interstellar space: Tiny specks of dust captured by a NASA spacecraft may be the first material from outside the solar system ever caught and brought to Earth.Researchers studying the contents of a capsule returned to Earth in 2006 at the conclusion of the Stardust spacecraft's primary mission believe that they have found seven remarkable specks on its collection panels.Although they weigh about 10 trillionths of a gram in all, the microscopic motes of "alien" dust described in the journal Science could alter astronomers' perception of the galaxy beyond our own stellar neighborhood.The Stardust mission was launched in 1999 on a seven-year, 3-billion-mile journey with two separate goals: to collect particles from the tail of the comet Wild-2 and to gather what bits of interstellar dust it could find.Scientists began examining the collection panels for dust soon after the capsule returned. It was a daunting task."It's not easy to find these things.… What they've done in this paper is hugely impressive," said Scott Messenger, a cosmochemist at NASA's Johnson Space Center who was not involved in the study.Once located, the specks could be analyzed to determine their makeup. That research continues, as does study to verify that the dust came from interstellar space and to look for still more dust motes in the panels.With the seven samples, scientists can examine the individual chemical and structural characteristics of single grains — grains that are proving to be a lot more diverse than many scientists expected.Some are large and fluffy (about 2 micrometers wide). Others are smaller and denser.Only two have survived largely intact. Others were smashed out of shape when they crashed into the aluminum foil in the collectors. One was so fast that it probably vaporized, leaving little more than a ghostly trail.Some of the particles are rich in sulfides, which many scientists did not expect — and such molecules could potentially serve as excellent catalysts for prebiotic chemistry, said study coauthor Rhonda Stroud, a nanoastronomer at the Naval Research Laboratory in Washington.Two of the fluffy particles sport a crystalline mineral known as olivine — which is surprising because many researchers thought that the extremes of space turned most particles into amorphous, unstructured lumps. That should certainly be the case with any particles blasted out of the heart of an exploding star, which is often how such dust grains are thought to spread through the galaxy and seed other solar systems."We're all made out of recycled dust — and we're just inherently interested in knowing what the dust we came from was like," Stroud said. "And this contemporary interstellar dust is giving us an idea of what new solar systems will be made of."Each particle has its own unique set of traits — which could mean that they may come from different neighborhoods in the galaxy, or different types of stars, or even the same type of star but in different life stages, Messenger said. Each could have a different cosmic story to tell.Although each grain is very different from the other, all were incredibly difficult to find.The grains were caught using collectors shaped like tennis rackets filled with incredibly light silica aerogel and bits of aluminum foil. Many particles that this fragile, airy material was trying to catch were traveling about 20,000 mph. It's like trying to stop bullets with cotton candy, Stroud said.But even after Stardust's successful touchdown, there was another daunting challenge: Finding the tiny tracks in the aerogel that could represent dust grains from outside this solar system. Scientists had to separate them from little shards of spacecraft that had lodged themselves in the delicate material. Scientists also had to examine their paths through the aerogel to make sure they qualified as interstellar dust.Finding tracks, and telling them apart from other impacters, requires examining an overwhelming number of blown-up microscopic images to look for the right kinds of tracks. It was an impossible amount of work for the team."We did the math," said lead author Andrew Westphal, a physicist at UC Berkeley. "It would take decades of work — and there was just no way we could do it."So researchers took what, at the time, was an unusual course — they crowd-sourced the work, recruiting more than 30,000 citizen scientists to comb through the images looking for telltale signs: long, carrot-shaped paths through the aerogel and tiny 3-micrometer craters pocking the aluminum foil. Collectively, they looked through more than 1 million images.The researchers have gone through a portion of the sample collector. They hope to find a few more once they finish, Westphal said.Bruce Draine, an astrophysicist at Princeton University who was not involved in the project, said more work needed to be done to confirm that these really are traces of interstellar dust. If so, then there could be many more tracks embedded in the aerogel — they just haven't been found yet, because most such dust particles are far smaller than these samples."To me, this seems like an exciting prospect," he added.Understanding dust on such an intimate level is also crucial to understanding measurements of the ancient universe, which are often shrouded by layers of these interstellar grains, Draine said.That's not an abstract concept, he added. Such dust — and its effect on the light that reaches our telescopes —- is at the heart of the controversy surrounding recent results from a team of scientists that claimed to have found evidence of the universe's cosmic inflation after the Big Bang.NASA Probe May Have Caught Dust from Interstellar Space, a FirstCharles Q. Choi - Space.comSeven tiny grains of rock captured by NASA's comet-chasing Stardust probe in 2004 may be visitors from the vast reaches of interstellar space, researchers say.These interstellar dust motes from Stardust are fluffier and more diverse than expected, findings that could one day shed light on the origins of the solar system, scientists added.Interstellar dust motes are bits of rock that permeate the enormous spaces between the stars. Supernovas and ancient stars produce interstellar dust, which contains elements such as carbon, nitrogen and oxygen that are necessary for life."By analyzing interstellar dust, we can understand our own origins," said lead study author Andrew Westphal, a planetary scientist at the University of California at Berkeley. "Just as people go to Africa to look for fossil hominids, say, 4.5 million years old, trying to understand the origins of humanity, we want to look at stuff that helped form the solar system 4.5 billion years ago."A comet-chaser captures interstellar dustNASA launched the Stardust spacecraft in 1999 on a mission to collect dust from the wake of Comet Wild-2 (pronounced "Vilt-2"). Stardust rendezvoused with the comet in 2004 and, in 2006, returned its sample container back to Earth via parachute.But while Stardust captured samples of Comet Wild-2 on one side of the craft's collector tray, the other side was pointed away from the comet to catch bits of interstellar dust in a stream emanating from about the direction of the constellation Ophiuchus. The tray was exposed to space for 195 days to capture particles in tiles of silica aerogel, a porous material resembling frozen smoke, which possesses a sponge-like structure that is 99.8 percent air.Now, nearly a decade after Stardust's samples reached Earth, a preliminary analysis of the material suggests that seven of the dust motes the probe caught may have origins outside the solar system. If that is confirmed, these tiny flecks of rock will represent the first specks of interstellar dust a spacecraft has ever returned to Earth."These are the very first contemporary samples of solid material from outside the solar system that we've identified," Westphal told Space.com. "Instead of looking at interstellar dust with telescopes, now we get to look at samples we collected from space with microscopes."Volunteer Stardust scientistsThe scientists enlisted the aid of volunteers around the world in the Stardust@home project. These citizen scientists, who called themselves "Dusters," helped study more than a million digital images of the microscopic impacts that particles made on the aerogel and on pieces of aluminum foil on Stardust located between the aerogel tiles on the collector tray."The Dusters as a community are really good at finding tracks, much better than we are," Westphal said.The researchers and citizen scientists analyzed 71 tracks that particles made as they crashed into the aerogel tiles. The analysis was unable to identify two of the tracks, but revealed that 66 were caused by spacecraft debris, leaving three potential grains of interstellar dust. Their discoverers named these particles Orion, Hylabrook and Sorok.Bruce Hudson, a retired carpenter in Ontario, Canada, chose the name Orion due to his affinity with space; Naomi Wordsworth, in Buckinghamshire in England, took Hylabrook from a poem by Robert Frost; and Westphal and his colleagues named Sorok."Sorok was track 40, and 'sorok' means 40 in Russian," Westphal said.The scientists also looked at 25 craters made on Stardust's aluminum foil, which was not originally planned as a surface to collect interstellar dust. Four of these pits were lined with partially melted residues that were chemically different from anything on the spacecraft, hinting they came from interstellar dust."They were splatted a bit, but the majority of the particles were still there at the bottom of the crater," study co-author Rhonda Stroud, a physicist and nanoastronomer at the Naval Research Laboratory in Washington, D.C., said in a statement.Dust grains from interstellar spaceThe interstellar dust motes Stardust collected are extremely tiny."Three of the biggest particles weigh roughly 3 picograms, or trillionths of a gram — a trillion of them would fit onto a teaspoon," Westphal told Space.com. "The other particles are more like a femtogram in mass, which is a thousand times smaller than a picogram. All in all, the amount of interstellar dust Stardust captured was less than a millionth the amount of cometary material it collectedThe researchers analyzed these dust grains using powerful microscopes. "One X-ray microscope we used is the Advanced Light Source at Lawrence Berkeley Laboratory, which is a synchrotron the size of a small shopping mall," Westphal said. "Others we used are the Advanced Photon Source near Chicago and the European Synchrotron Radiation Facility in Grenoble, France, which are the size of large shopping malls. These are instruments we could never hope to fly in space — that's one major advantage of sample return missions."These seven grains proved surprisingly diverse in size, composition and structure. The small ones differ greatly from the large ones, and may have experienced different histories."The relatively simple picture of interstellar dust grains more or less having the same structures is not right," Westphal said. "Each particle must have its own individual complicated history."Three of the particles also contained sulfur compounds. This is significant, as some astronomers previously argued sulfur does not occur in interstellar dust particles, the researchers said.In addition, many of the bigger particles were unexpectedly fluffy, made up of an agglomeration of other particles. By contrast, the simplest models of interstellar particles suggest the motes should each consist of a dense particle."The fact that the two largest fluffy particles have crystalline material — a magnesium-iron-silicate mineral called olivine — may imply that these are particles that came from the disks around other stars and were modified in the interstellar medium," Westphal said in a statement. "We seem to be getting our first glimpse of the surprising diversity of interstellar dust particles, which is impossible to explore through astronomical observations alone."Galaxy samples locked in space dustScientists have previously looked at interstellar dust grains within primitive meteorites, and have also used aircraft to collect interstellar dust motes in Earth's stratosphere that probably came from comets.However, these are not contemporary interstellar dust grains like the ones Stardust returned. "We think those are much older than the solar system, survivors of the violent process involved in converting the solar nebula into the solar system," Westphal said. "They don't fully represent what interstellar dust is like, since they had to be tough to survive, while other stuff that is more fragile did not survive well at all."In comparison, the dust from Stardust "is relatively new, since the lifetime of interstellar dust is only 50 to 100 million years," study co-author Anna Butterworth, a research physicist at the University of California, Berkeley, said in a statement. "We are sampling our contemporary galaxy."The amount of interstellar dust particles Stardust collected is unexpectedly small based on observations of interstellar dust carried out by the earlier Galileo and Ulysses space probes, Westphal said."The number of particles Ulysses and Galileo saw was much larger than accounted for by astronomical observations of interstellar dust," Westphal said. "Our observations are more in line with the astronomical observations."One possible explanation for this discrepancy comes from the fluffiness some of the particles. "The pressure from sunlight is significant on such particles, and if the particles are sufficiently fluffy, instead of accelerating toward the solar system because of the sun's gravity, it might not make it into the solar system." In other words, when interstellar dust tries to get close to the sun, sunlight might be pushing many of the particles outward with more force than gravity draws them inward. Ulysses and Galileo may therefore have seen more interstellar dust particles than Stardust because they were in more-distant regions of the solar system.A taste of interstellar space?Westphal cautioned that the researchers still need to carry out additional tests before they can definitively say that these are pieces of debris from interstellar space. The scientists will analyze oxygen isotopes in the specimens; stable atoms of oxygen have anywhere from eight to 10 neutrons in their nuclei, and matter in the solar system has proportions of these distinct isotopes of oxygen that differ from materials found elsewhere in the galaxy.The potential interstellar material is difficult to analyze because there is so little of it. However, "instruments do exist to do these measurements, ones that did not exist when the spacecraft was launched," Westphal said. "That's the huge advantage of having sample- return missions. You can use state-of-the-art technology you could never fly in space, and that did not exist when the missions flew."The scientists noted that more interstellar dust could be discovered from the Stardust collector trays. An additional 100 tracks found by Dusters have yet to be analyzed, and only 77 of the 132 aerogel tiles have been scanned to date. Westphal said he expected to find no more than a dozen particles of interstellar dust in total."I invite people to participate in the ongoing Stardust@home project, and just have fun looking for interstellar dust," Westphal said. "Citizen scientists are making real contributions there."Westphal noted, "This is only the first glimpse we have of the diversity and complexity of interstellar particles. It's too early yet to take what we've learned about the interstellar medium here to learn more about the formation of the solar system, because we have so few particles in our collection. What we want now is a new mission whose goal is collecting hundreds or thousands of particles, not just a small handful."The scientists detailed their findings in the Aug. 15 issue of the journal ScienceStardust team reveals first specks of interstellar dustRachel Ehrenberg – New ScientistCaptured dust grains that flew into our solar system from interstellar space are providing our first on-the-ground glimpse of the stuff between the stars. Having the particles in hand will hopefully shed light on the chemistry of the cosmos."Dust grains are the place where things happen in space – they provide a place for molecules to meet," says Anthony Remijan at the National Radio Astronomy Observatory in Charlottesville, Virginia, who was not involved with the research. "It's very exciting, we've actually grabbed a piece of the universe that we can examine in the lab."The grains were captured by NASA's Stardust spacecraft, which launched in 1999 and collected particles from the tail of comet Wild 2. On the way to the comet, the spacecraft also exposed its dust collectors – made of aerogel and aluminium foil – to a dust stream thought to come from interstellar space. It delivered its precious cargo to Earth in 2006.Since then, the Stardust team has combed through millions of close-up images of the spacecraft's dust collectors, an effort aided online by more than 30,000 citizen scientists, dubbed "Dusters", who participated in the Stardust@home project.Now, the team has published results on the physical analyses of seven samples of debris that hit the collectors that they are confident came from interstellar space.Liquid smokeAlthough they have not yet found a smoking gun for interstellar origin, the team has ruled out a number of other origins for the grains. They showed that the grains contain a magnesium-iron-silicate mineral called olivine, meaning it could not have come from the spacecraft itself or its collectors.The impact tracks that the grains made in the collectors' aerogel – often called liquid smoke because its density approaches that of air – were also consistent with coming from high-speed interstellar particles. Because of the way the sun moves through the galaxy, material from interstellar space enters the solar system from a particular direction, creating a wind. To maximise the chance of catching interstellar grains, Stardust opened the collectors when the spacecraft was heading in the same direction as these interstellar winds.The team expected any grains they caught to be amorphous blobs, because earlier calculations suggested that the harsh radiation environment of the interstellar medium should smear out crystalline structure, and that the grains would be moving at velocities of at least 25 kilometres per second. Such velocities would mean that when they struck the collectors, they would probably have been crushed somewhat.Orion and HylabrookBut surprisingly, the grains they caught were intact. Two of the grains, dubbed Orion and Hylabrook by their Duster discoverers, are unexpectedly large – about two micrometres in diameter – and have an intricate structure, like fluffy snowflakes."Our models say they shouldn't be so big and they are more crystalline than expected," says Bruce Draine at Princeton University, an authority on interstellar dust. "But that doesn't mean they aren't interstellar grains."The particles could have survived thanks to radiation pressure exerted by the sun slowing them down to a velocity in the region of 5 kilometres per second, says Stardust scientist Andrew Westphal at the University of California, Berkeley. Similarly slow collisions created in lab experiments yield similar aerogel tracks as those left by the examined particles.Building blocksIt's too early to say how the dust grains might affect existing theories on the formation of the solar system or other galactic matters, says Westphal, who compares the effort to analysing a few bits of ancient bones in Africa and trying to say something meaningful about human evolution.But there's much more to discover. The team has only examined 71 tracks in the aerogel and 25 craters in the aluminium foil, and more than 150 tracks have yet to be investigated."The interstellar medium is interesting because fundamentally, it's what we're made of," says Westphal. "Like the Apollo mission, these samples are undoubtedly going to be studied for years to come."How A Comet-Chasing Spacecraft 'Likely' Brought Interstellar Dust Back To EarthElizabeth Howell – Universe TodayIf the scientists are right, a NASA spacecraft brought stuff from outside the solar system back to Earth. The Stardust spacecraft, which was originally tasked with chasing after Comet Wild 2, brought our planet seven grains that look fluffier than expected.While the scientists say that more tests are needed to determine these particles originated from outside the solar system, they are confident enough to publish a paper on the findings today."They are very precious particles," stated Andrew Westphal, a physicist at the University of California, Berkeley's space sciences laboratory who led 65 co-authors who created a paper on the research.What's more, the findings came with a big assist from volunteers who participated in a crowdsourced project to look at dust tracks in Stardust's aerogel detector.The Stardust spacecraft was launched in February 1999 to gather samples of Comet Wild 2 and return them to our planet. Stardust also attempted to collect interstellar dust twice in 2000 and 2002 for 195 days. Its mission was extended in 2011 to look at Comet Tempel-1, the comet that Deep Impact crashed into.The sample return capsule, however, separated from the spacecraft in January 2006 as planned while Stardust flew by our planet, landing safely on Earth. Comet samples and interstellar samples were stored separately. Scientists then began the work of seeing what the spacecraft had picked up.Here's where the volunteers came in. These people, who called themselves "Dusters", participated in a project called Stardust@home that put more than a million images online for people to examine.Three particles, dubbed "Orion", "Hylabrook" and "Sorok", were found in the aerogel detectors after volunteers discovered their tracks. (Many more tracks were discovered, but only a handful led to dust. Also, 100 tracks and about half of the 132 aerogel panels still need to be analyzed.)Four more particles were tracked down in aluminum foils between the aerogel tiles. That wasn't originally where they were supposed to be collectors, but despite their "splatted" and melted appearance there was enough left for scientists to analyze. (About 95% of the foils still need to be examined.)So what did the scientists see? They describe the particles as fluffy, sometimes appearing to come from a mix of particles. The largest ones included crystalline material called olivine (a magnesium-iron-silicate). More testing is planned to see what their abundances of different types of oxygen are, which could help better understand where they came from.Additionally, three of the foil particles had sulfur compounds, which is controversial because some astronomers believe that isn't possible in interstellar dust particles.The research was published in the journal Science. Twelve more papers on Stardust will be published in Meteoritics & Planetary Science.First dust grains from outside the Solar SystemCitizen-science project identifies particles caught by NASA craft as having likely interstellar origin.Nicole Skinner – NatureSeven particles captured by a NASA probe could be the first known samples of interstellar dust to be brought back to Earth.For the past eight years, a team of researchers — with the help of citizen scientists around the world — have been scanning and analysing the samples brought back to Earth by the Stardust spacecraftInterstellar dust flows continuously into the Solar System, but it is extremely sparse, so capturing particles is difficult. Until now, everything scientists knew about such dust has come from analysing spectra of scattered and absorbed light from the interstellar medium. But these observations do not reveal much about the properties of individual particles.A consortium of 65 scientists studied the microscopic impacts that particles made on Stardust's collectors, which are composed of tiles made from an ultralight material called aerogel. They report their findings today in Science1 and in 12 other papers in Meteoritics & Planetary Science.First of a kindAndrew Westphal, a physicist at the University of California, Berkeley, and lead author of the Science paper, explains that his team faced a chicken-and-egg problem. "Because we had never seen interstellar dust, it was difficult to recognize and differentiate it from interplanetary dust particles," he says. "What we did know were the expected trajectories of the particles as they propagate through the heliosphere," adds Westphal, referring to the vast region of space that covers the Solar System in which the solar wind has influence.In other words, researchers were looking for dust grains coming from a specific direction in the sky. Westphal says the situation is analogous to driving down a highway in a snowstorm: snowflakes hit the windshield more than they hit the side windows. Similarly, as the Solar System orbits the Galaxy, we see dust coming from one particular direction in the sky because of our motion with respect to the interstellar medium.Of the seven candidate interstellar particles, three — relatively large, at around two microns each — were found on the aerogel tiles of Stardust's collector. The other four particles, much smaller at just a few tenths of a micron across, were found in aluminium foils located between the tiles. Just over half of Stardust's aerogel tiles have been scanned to date, but Westphal does not expect to find more than a dozen particles in the entire collection.Two of the candidates were revealed at a meeting in 2010 (see 'Volunteer army catches interstellar dust grains'), but the team did not publish their analysis of those paricles — plus five more — until now.Don Brownlee, an astronomer at the University of Washington in Seattle and Stardust's principal investigator, says that he and his colleagues were quite pleased with the results. "We did not know how successful the collection would be, either in the aerogel tiles or aluminium foils, because no one had ever captured high-speed interstellar material before."The analyses show that the seven candidate particles are all different from each other in both structure and composition. "This is quite exciting," says Westphal, "because it's telling us this is a much richer and diverse collection of material than we originally expected."Dust lotteryAdolf Witt, an astronomer at the University of Toledo in Ohio, considers this a possible breakthrough development: "These are indeed intriguing results that have been awaited by the interstellar-dust community for a long time."Priscilla Frisch, an astronomer at the University of Chicago in Illinois, agrees. "Dust-grain models will need to be revised to take into account these results," she says. "Interstellar dust particles are a cosmic laboratory for studying the physics of microscopic surfaces and Stardust's results provide a more realistic basis for evaluating the way the grains are charged and the scattering of radiation due to them."Crucial to the project were the 30,714 volunteers participating in Stardust@home, one of the first online citizen-science initiatives. They collectively carried out more than 100 million image searches looking for tiny interstellar dust impacts on magnified fields of the aerogel.Naomi Wordsworth from Buckinghamshire, UK, saw the project advertised on the BBC and "thought it sounded fabulous to participate in a real science project open to anyone who wanted to use their skills to help". In 2010, four years after becoming a 'duster', she received an email from Westphal telling her that she had discovered one of the interstellar dust candidates. "It felt like winning the lottery," says Wordsworth. As a reward for her discovery, she was allowed to choose a name for the particle — Hylabrook, after her family's home.To confirm these preliminary results, the next crucial step will be to measure the relative oxygen isotope abundances in the particles through mass spectroscopy. The team has the necessary instruments, Westphal says, but the particles are still embedded in the aerogel and they are very difficult to handle. "We have such a small collection that we want to be absolutely certain the particles will not be lost. The plan is to spend the next three years, approximately, refining our techniques."Former NASA Chief: U.S. Not On A Path To MarsMark Carreau - Aviation WeekU.S. policymakers and others passionate about a human Mars landing are delusional if they believe the nation that ended its first foray into deep space with the Apollo moon landings is on a calculated path to the Red Planet, according to former NASA administrator Mike Griffin.Current efforts, focused on NASA's Asteroid Retrieval Mission (ARM) as a springboard, are fizzling because the U.S. is not the "spacefaring" nation most assume, he told the 17th Mars Society conference in League City, Texas, as part of an Aug. 9 session on exploration."There are reasons other than technical why that has not happened. It isn't about the money," Griffin told the conference organized around Mars Direct, the society's strategy for establishing a sustained human presence on Mars without intermediate destinations by using current technologies and extracting fuel, life support and construction materials from the planet's atmosphere and soil."The answer is because we are not a spacefaring nation," Griffin asserted. "The bottom line, for me, is that we have better stuff in museums than we have in operations today. I can't think of another technical discipline in which that statement would be true."As administrator during former President George W. Bush's second term, from 2005 through President Barack Obama's inauguration in 2009, Griffin led the early implementation of the Constellation program, an initiative to establish a lunar base as the predicate for a long-term strategy of reaching Mars and destinations beyond with humans.The strategy was quickly dismantled by the Obama administration, which cited a lack of funding and schedule delays. ARM, however, is rapidly becoming the focus of similar concerns, raised most recently by the National Research Council but also by congressional auditors and the agency's own inspector general.ARM's goals include the robotic capture of a small asteroid or a large, boulder-sized piece of an asteroid that can be steered into a stable orbit around the Moon to demonstrate solar electric propulsion. The new cislunar address would permit U.S. astronauts to visit the object by the mid-2020s using the Orion crew capsule and Space Launch System hardware that NASA considers key to reaching Mars in the mid-2030s.If the U.S. was truly spacefaring, Mars would already have a human presence, Griffin said. He characterized the enterprise as requiring commitments much deeper than those advanced by presidential administrations and Washington legislators."When it matters to us as a society, it will happen," he said. "This means that as a society we believe that being on the space frontier — second to none — will bring benefits to future generations."This includes U.S. influence on a range of global matters as well as new discoveries and economic opportunity, he suggested.The U.S. retreat from deep space after Apollo was akin to the U.S. Navy deploying just a single aircraft carrier, according to Griffin."The technology of our time, if we put it back together, would take us back to the Moon. With a little more effort, the technology of our time will take us to Mars," he said. "The technology of some future time will inevitably cover the Solar System with human beings. The question is what language will they speak, what culture will they share and what morals and values will they propagate."Sierra Nevada's space plane in the chase with SpaceX and Boeing to win NASA nodCompany's Dream Chaser orbital glider has yet to achieve orbit but still is a contender to ferry Americans to and from space stationGeoffrey Giller – Scientific AmericanNASA ended its space shuttle program in 2011, in part to focus on other goals such as putting humans in deep space and on Mars. But the agency still needs a reliable and cost-effective way to get astronauts to and from the International Space Station (ISS). For the past several years it has been paying Russia to do just that. But soon, it will no longer have to do so.Since 2010 private companies have been competing for a lucrative opportunity: to provide routine transport of American astronauts and cargo to the ISS as well as deliver other low Earth orbit payloads. Now three companies are closing in on that goal; NASA will be announcing the winner or winners later this year. With only a couple months left in a four-year-long race, two well-known spaceflight heavy hitters—SpaceX and Boeing—have been joined by a seeming underdog: Sierra Nevada Corp., a 51-year-old company with spaceflight cred that includes supplying the Virgin Galactic SpaceShipTwo engine.In 2010 NASA announced the Commercial Crew Program, with a goal of developing a "safe, reliable and cost-effective crew transportation to low Earth orbit," says Stephanie Martin, the program's spokesperson. This strategy takes advantage of the flexibility, efficiency and adaptiveness of private companies in making competitive technologies that respond to a growing space-related business marketplace while reducing taxpayer expenses. According to the Space Foundation's 2014 Space Report, the space economy is globally valued at about $314.2 billion, a figure that includes everything from telecommunications to weather forecasting to navigation to launches of military satellites. Other organizations would also benefit from the commercial development of more vehicles capable of reaching space at lower costs. "Researchers might want to have access to low Earth orbit to do experiments," Martin says. Space tourism is another possibility; one consulting firm estimated that space tourism could be worth over a billion dollars by 2021.NASA awarded five companies a total of nearly $50 million through the first round of funding in 2010 to develop spacecraft, launch systems and support equipment, including Blue Origin, Paragon Space Development Corp. and United Launch Alliance as well as those involved in manned vehicle development like Boeing and Sierra Nevada. Over the subsequent rounds of funding SpaceX entered the fray whereas other companies dropped out or, in some cases, entered into "unfunded Space Act Agreements," allowing the firms to continue working with NASA scientists but without receiving more funding.The latest round of the competition, awarded in 2012, gave $10 million to Sierra Nevada for the recently completed safety testing of its vehicle, called Dream Chaser. In July the company completed another milestone by successfully testing several of Dream Chaser's major systems, including life-support as well as environmental and thermal controls. Earlier in the month it also tested the vehicle's main propulsion system.With the completion of this latest safety-testing milestone of key systems, Mark Sirangelo, corporate vice president of Space Systems at Sierra Nevada, says that this stage of the Dream Chaser program, before NASA announces a winner, is "90 to 95 percent complete," with at least one more landing flight test and tests of the thrusters remaining. The company has a November 1, 2016, date set for the first unmanned launch of its spacecraft into orbit. If all goes as planned, it would stage a second launch about six months later and would then apply to NASA to certify the Dream Chaser as ready to take a crew to the ISS, Sirangelo says.Sierra Nevada's crew transportation vehicle design differs markedly from that of Boeing or SpaceX. Although all three designs use a traditional vertical launch rocket to get their vehicles into space, Sierra's competitors are building capsules that are designed to land back on Earth using either parachutes and airbags (in the case of Boeing's CST-100) or thrusters (SpaceX's Dragon capsule). But the Dream Chaser uses a lifting-body design—essentially, it is a space plane that resembles a small version of the space shuttle and, like it, can land on a runway. The design is based on a spacecraft, the HL-20, that NASA developed in the 1980s and '90s but decided not to pursue. Sirangelo says that the lifting-body design is ideal, because it can land with a lower g-force than a capsule; instead of plummeting back to Earth slowed by parachutes or thrusters, it glides. That's useful in a number of scenarios, according to Sirangelo. A higher g-force, such as what could be experienced in a returning capsule, could cause problems if a delicate experiment was being returned from the ISS or if an astronaut were sick or injured. The space plane design is also more quickly accessible when it returns, as it can land on any commercial runway large enough for a Boeing 737 airplane, Sirangelo says, unlike a capsule landing in a potentially remote area. This past October Sierra Nevada tested the automated landing system by dropping the Dream Chaser from a helicopter; the vehicle's approach to the runway was spot-on, although a mechanical malfunction prevented one of the wheels from deploying, sending the vehicle skidding off the runway. Nevertheless, both Sierra and NASA deemed the test a success.NASA hopes to have astronauts flying on the winning vehicle by 2017. Later this summer or early this fall the agency plans to announce the competition winner(s), which will eventually involve transportation of astronauts to the ISS. NASA's Martin says it is possible that the agency may choose more than one design for crew transportation. "We do look forward to continuing to work with all of our partners," even those that don't receive the next contract, she says—down the road NASA may want the option of having multiple transportation vehicles to choose from.Of course, Sierra Nevada may end up on that also-ran category. Roger Handberg, professor of political science at the University of Central Florida and an expert on space policy, for one, is dubious about the company's chances. SpaceX, which he thinks is the current favorite, has already completed several successful missions to and from the ISS with an unmanned version of its Dragon capsule whereas the Dream Chaser has not yet been in orbit. "It's hard to beat something with nothing," he says. "Until you fly, you're going to have that problem." Sierra has also received less funding than its competitors; to date the Commercial Crew Program has awarded the company more than $363 million whereas during the same time period Boeing has received $621 million and SpaceX $545 million. These discrepant figures are due in part to the fact that Sierra Nevada had "the most significant amount of risk reduction and technology development work to do," according to a statement by NASA when it awarded the latest round of funding in 2012.Complicating matters, both the Boeing and Sierra designs rely on Atlas 5 rockets to get to orbit, which in turn rely on Russian-made RD-180 engines, Handberg notes. In May Russia announced that the U.S. could no longer use Russian-made engines for military launches; it is not clear whether that includes voyages to the space station. Sierra's Sirangelo, however, does not think that the recent tensions with Russia will affect future space missions. Martin agrees: "We've had great cooperation with Russia," she says. "We'll always continue to work with them on the International Space Station."Shuttle replica makes final landing atop 747 at Space Center Houston200-foot-tall crane was operated by Dutch company Mammoet, based in RosharonHarvey Rice – Houston ChronicleAs hundreds of eager onlookers watched, a crane on Thursday lifted the space shuttle replica Independence nearly three stories high to its resting place atop a Boeing 747 at Space Center Houston, where visitors will eventually be able to tour the attraction.The delicate lift to the crown of the 63-foot 747 took about 40 minutes. The 122-foot Independence was attached to a 200-foot tall crane operated by Mammoet , a Dutch company whose U.S. offices are based in Rosharon, Brazoria County."What is so spectacular here is that we are able to contribute to a piece of history," said Guus Stigter, Mammoet's director of global key accounts.The lift was challenging because of the awkward weight distribution of the replica and the safety concerns for the hundreds of spectators, Stigter said.The crane lifted the replica to a height of 150 feet before lowering it onto the back of the shuttle plane, NASA 905, sitting on a 15-inch concrete foundation.The Clear Lake Suzuki Strings with musicians from Pasadena's Rayburn High School played variations on "Twinkle, Twinkle Little Star," interspersed with recorded music, during the lift.The wind caught the wings and made it sway as it was being lowered, a tense moment for Space Center Houston CEO Richard E. Allen Jr. "The wind was the biggest concern we had and for whatever reason we got a gust," Allen said. But Mammoet workers had the Independence tethered to long lines they used to stabilize it and the docking went on without a hitch. Workers began welding the replica in place as soon as the match was complete."It's really, really amazing," said Tam Tran, 46, who brought sons Phillip, 12, and Austin, 10, to watch the marriage of aircraft and spacecraft. "I think it's cool because they had the space shuttle and they added the plane to make it a bigger landmark," Phillip said.Visitors will eventually be able to enter the replica cockpit, the mid-level shuttle compartment and the 747 through a tower equipped with a staircase and two elevators, Allen said. Space Center Houston is $2.2 million short of the $12 million it needs to complete the exhibit."It's a celebration of our past accomplishments," said John Elbon, Boeing Space Exploration vice president. "Even more important, it's an opportunity to look forward ... and inspire the next generation of kids."The lift to the top of the 747 is the final step in a long journey to Houston that began more than two years ago at Kennedy Space Center in Florida. The replica was shipped by barge across the Gulf of Mexico in May 2012 and unloaded at the Johnson Space Center barge dock on Clear Lake. It took a full day to lift the replica from the barge and weld it onto a transporter, then three hours to move it a mile to Space Center Houston.The 747, used to transport space shuttles from landing sites in California and New Mexico back to the launch site in Florida, was moved to Space Center Houston in April from Ellington Field, an 8-mile journey that required breaking the aircraft into nine parts and reassembling them at the Space Center.The Independence then had to make another 400-yard journey on a special transporter to the spot where the final lift was made Thursday.NASA Chief On Past And Future Of U.S. Space ProgramWBUR-FMNASA Administrator Charles Bolden joins Here & Now's Jeremy Hobson for a wide-ranging conversation about the past and future of NASA's effort to explore the universe.Bolden discusses the future of the International Space Station and U.S. cooperation with Russia, and he weighs the chances that NASA will discover life in the Milky Way galaxy.Bolden says that the U.S. will be able to send astronauts to space again by 2017, with the help of American private industry.He also describes why he thinks the agency is more inspiring to minority children and girls today than it was during NASA's height in the 1960s.Interview HighlightsOn whether Americans should worry about NASA's partnership with Russia"I am not concerned, because of the relationship that we have managed to preserve with our partner agency inside Russia, the Russian space agency. I will caveat that by saying that, like us, they're a part of the government, so one never knows what can happen. But based on the day-to-day relationships and what's going on with our people, about 30 of them that work in-and-out of the mission control center in Moscow every day, our astronauts who are training at the Gagarin Cosmonaut Center on the outskirts of Moscow, the indications we have are that they are as interested and as enthusiastic as we about maintaining our partnership."On using private industry for space travel"I am certain that our path is the correct path. No other nation is able to do what we're able to do right now. No other nation has the capability to call on their industry to provide the kinds of services that we can do. Right now, all of our international partners rely on either heavily subsidized or government-run means to do things, and that's the way the U.S. used to do it, but we don't need to do that anymore. If you look at what our intelligence community is doing, if you look at what the military is doing, we are leading the way. NASA has demonstrated that U.S. industry is reliable, dependable, and in fact — in relative terms — cheap, compared to what it costs us to maintain the infrastructure to do it all ourselves."On inspiring the astronauts of the future"I was not unlike many young African American kids, young kids of color growing up in the segregated South. We were conditioned to believe that there were limits to what we could do. My mom and dad were teachers and so they tried to make sure that I never put an artificial limitation on myself, and in spite of all their efforts, I did. It took Ron [McNair] to wake me and shake me.""I think in many ways we are much more inspiring than we were in the Apollo era. Do you know how many black kids had any hope of becoming an astronaut in the Apollo era? Zero. Do you know how many girls had any hope of becoming an astronaut in the Apollo era? Zero. Why? Because there was no one like them, and they knew you had to be a test pilot and they assumed you had to be white. That is no longer the case. That paradigm was shattered by the space shuttle program, an incredible 30-year program. Everybody talks about its technological accomplishments — let me tell you, as a human being I think its greatest accomplishment was opening the doors of space exploration to everyone on this planet."Space Station Supply Ship Exits, Now Packing TrashMarcia Dunn – APA commercial cargo ship has ended its monthlong space station visit.Astronauts aboard the International Space Station released the Cygnus supply ship, now full of trash for disposal early Friday. They parted company 260 miles above Africa's southwest coast.Orbital Sciences Corp. launched the Cygnus from Virginia in mid-July under a NASA contract. The unmanned craft hauled more than 3,000 pounds of crucial cargo to the orbiting outpost. Now it's loaded with rubbish, some 3,500 pounds' worth."All the best wishes," German spaceman Alexander Gerst radioed to the company's flight controllers.On Sunday, the Virginia-based Orbital Sciences will steer the craft down through the atmosphere to burn up. The six space station astronauts will attempt to record the fiery re-entry for engineering analysis. The same documentation will be done when a European supply ship departs early next year. That ship, launched from French Guiana, delivered its shipment just a few days ago.NASA and its international partners — Russia, Europe, Japan and Canada — want to learn as much about atmospheric re-entry as possible to prepare for the space station's eventual demise in the decade or two ahead.Orbital Sciences Corp. is one of two U.S. companies hired by NASA to deliver space station goods. The California-based SpaceX will make its next supply run next month.ENDMore at www.spacetoday.net
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