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Sonntag, 16. November 2014 - 16:45 Uhr

Raumfahrt - Lang verschollenen Apollo-Mondmission Bänder entdeckt

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Physics Professor, Brian O'Brien in his Floreat home with one of many Moon Mission data tapes he has as part of his involvement in NASA's moon program. 
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Eight years ago, NASA put a call out for misplaced tapes containing important data collected from Apollo 11 - the first manned mission to the Moon.
So desperate was its search that in 2009, it even set up a committee to try to find the tapes, with thousands of rolls believed to be missing.
So how did 177 rolls of the tapes end up in Perth?
Australian physicist Brian O'Brien was thrilled when his radiation detector was one of seven experiments NASA chose from 90 proposals to accompany Apollo 11 to the Moon in 1969.
NASA was also concerned that his - and the other experiments - would be jeopardised by the Moon's fine dust and would need covers.
Yet, it had no plans to measure the dust and see whether its fears were justified.
So, before the mission, Professor O'Brien invented a simple dust detector and NASA added it to the inaugural lunar landing.
By the time Neil Armstrong took his first tentative steps on the Moon on July 20, 1969, Professor O'Brien was working at the University of Sydney.
Rolls of old-fashioned magnetic tapes started arriving at his university office every three days and, when he moved to Perth to be the first head of WA's Environment Protection Authority in 1971, dozens of them went with him.
The dust detector, which was only about 10cm high, also accompanied the Apollo 12, 13, 14 and 15 missions - so the tapes kept rolling in and in all, Professor O'Brien was sent 177 rolls.
Although they are difficult to read because of their outdated technology, Professor O'Brien still believes there is a lot to learn from the contents.
"We have started going through them and made a dozen interesting discoveries, which have been published," he said.
So in 2006 when NASA announced that its tapes were missing and the data no longer existed, Professor O'Brian contacted the space agency about his rolls.
"We don't know what they did with the originals, but they were pleased that we could supply them with data," he said.
Professor O'Brien served as EPA chairman from 1971 to 1977.
Quelle: The West Australian

Tags: Raumfahrt 

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Sonntag, 16. November 2014 - 12:15 Uhr

Astronomie - Erste Beobachtungen von Objekten aus der Oort Wolke

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Spectrum of C/2013 P2 (Pan STARRS) from the visible (blue points) to near infrared (red points) compared to other solar system small bodies:  comets (represented by comet 6P/d’Arrest), Trojan asteroids, outer asteroid belt red D-type asteroids, and ultra-red Kuiper belt objects (TNOs).  This shows that C/2013 P2 looks very different from other small body surfaces.

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Astronomers are announcing today the discovery of two unusual objects in comet-like orbits that originate in the Oort cloud but with almost no activity, giving scientists a first look at their surfaces. These results, presented today at the annual meeting of the Division of Planetary Sciences of the American Astronomical Society in Tucson, Arizona, are particularly intriguing because the surfaces are different from what astronomers expected, and they give us clues about the movement of material in the early solar system as the planets were assembled.
On August 4, 2013 an apparently asteroidal object, C/2013 P2 Pan-STARRS, was discovered by the Pan STARRS1 survey telescope (PS1) on Haleakala, Maui, Hawaii.  What made this object unique is its orbit – that of a comet coming from the Oort cloud, with an orbital period greater than 51 million years, yet no cometary activity was seen.   The Oort cloud is a spherical halo of comet nuclei in the outer solar system that extends to about 100,000 times the Earth-sun distance, which is known as 1 astronomical unit, or 1 AU.
“Objects on long-period orbits like this usually exhibit cometary tails, for example comet ISON and comet Hale Bopp, so we immediately knew this object was unusual,” explained team leader Dr. Karen Meech (Institute for Astronomy, University of Hawaii at Manoa).  “I wondered if this could be the first evidence of movement of solar system building blocks from the inner solar system to the Oort cloud.”
Follow-up observations in September 2013 with the 8-meter Gemini North telescope on Maunakea, Hawaii, hinted at faint, low-level light reflected off a dusty tail.   This tail remained through the object’s closest approach to the sun (2.8 times the Earth-sun distance, within the outer asteroid belt) in February 2014, but the object didn’t get much brighter.
When the object was observable again in the spring, the team used the Gemini North telescope to obtain a spectrum of the surface, which showed that it was very red, completely different from comet or asteroid surfaces, and more like the surface of an ultra-red Kuiper belt object. 
“We had never seen a naked (inactive) Oort cloud comet, but Jan Oort hypothesized their existence back in 1950 when he inferred the existence of what we now call the Oort cloud. Oort suggested that these bodies might have a layer of “volatile frosting” left over from 4.5 billion years of space radiation that disappears after their first pass through the inner solar system.  Maybe we are seeing the first evidence of this,” said Dr. Olivier Hainaut of the European Southern Observatory.
While the team analyzed their observations of comet C/2013 P2 Pan-STARRS, a second object was discovered. C/2014 S3 Pan-STARRS was discovered through the NASA-sponsored Near Earth Object Survey on the PS1 telescope on September 22, 2014.  Like C/2013 P2 Pan-STARRS, it was on the same type of cometary orbit and also showed minimal activity.  Team member Dr. Richard Wainscoat (IfA, UHM) commented, “With PS1 now exclusively involved in surveying the solar system for Near Earth Objects (NEOs), we expect to find many fascinating objects.  This will help revolutionize our understanding of the early solar system.”
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Images of C/2013 P2 (left) obtained using the Gemini North 8-meter telescope on 2013 September 4 when it was 3.29 AU from the sun, and of P/2014 S3 (center) obtained using the CFHT on September 26, 2014 when it was 2.12 AU from the sun. Both images have been processed to remove most of the background stars and galaxies to enhance the visibility of the faint dust tails. These images of the two barely active distant comets contrast sharply with another Oort cloud comet imaged at a similar distance, 3.04 AU, C1995 O1 Hale-Bopp. This image was obtained by K. Meech, O. Hainaut, and J. Bauer on 9/17/96. Compared with it, the Pan-STARRS comets are wimps.
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The team immediately followed up this second object with the Canada-France-Hawaii Telescope (CFHT) on Maunakea, to obtain data on the object’s colors, and to their surprise, this one has colors similar to inner solar system asteroid material.
“While the orbit of C/2014 S3 is similar to objects in the so-called Damocloid class, which are believed to be extinct comets, the surface of this object looks nothing like previously observed Damocloids.  This is the first outer solar system object which matches inner asteroid belt material,” said team member Henry Hsieh (Academia Sinica, Taipei, Taiwan).  “Damocloids typically have moderately red surfaces, but this is much more blue.  These may be the first of a new class of objects,” noted team member Bin Yang (ESO Santiago, Chile).
While the orbit of C/2014 S3 Pan-STARRS took it closer to the sun than C/2013 P2 in mid August 2014 (2.0 AU—between the asteroid belt and the orbit of Mars), it also barely had a tail. 
“I’ll be thrilled if this object turns out to have a surface composition similar to asteroids in the inner part of the asteroid belt.  If this is the case, it will be remarkable for a body found so far out in the Solar System, especially since it exhibited a tail that may be due to volatile outgassing,” commented Meech.  “There are several models that try to explain how the planets grew in the early solar system, and some of these predict that material formed close to the sun could have been thrown outward into the outer Solar System and Oort cloud, where it remains today.  Maybe we are finally seeing that evidence.”
The report is being presented by Drs. Karen Meech, Jan Kleyna, Jacqueline Keane, Richard Wainscoat of the University of Hawaii at Manoa’s Institute for Astronomy (Honolulu, Hawaii), Bin Yang (Santiago, Chile) and Olivier Hainaut (Garching, Germany) from the European Southern Observatory, Henry Hsieh from Academia Sinica (Taipei, Taiwan), Ryan Park and James Bauer from the Jet Propulsion Laboratory (Pasadena, California), Peter Veres from Comenius University (Bratislava, Slovakia), and Bhuwan Bhatt and Devendra Sahu from the Indian Institute of Astrophysics (Bangalore, India).
Based in part on observations obtained at the Pan-STARRS1 Survey telescope, made possible through the Pan STARRS science consortium, in part at the Gemini Observatory which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership; in part on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council of Canada, the Institute National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii. The observations are also based in part from the Himalayan Chandra Telescope, operated by the Indian Institute of Astrophysics, Bangalore, and through the use of the 72-inch Perkins telescope at Lowell Observatory in Arizona.
This work was supported by NASA through the NASA Astrobiology Institute under Cooperative Agreement No. NNA09DA77A issued through the Office of Space Science, and in part based upon work supported by the National Aeronautics and Space Administration under Grant No. NNX12AR65G and Grant No. NNX14AM74G issued through the NEO Observation Program.
Founded in 1967, the Institute for Astronomy at the University of Hawaii at Manoa conducts research into galaxies, cosmology, stars, planets, and the sun. Its faculty and staff are also involved in astronomy education, deep space missions, and in the development and management of the observatories on Haleakala and Maunakea. The Institute operates facilities on the islands of Oahu, Maui, and Hawaii.
The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space. The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the U.S. National Science Foundation (NSF); the Canadian National Research Council (NRC); the Brazilian Ministério da Ciência, Tecnologia e Inovação (MCTI); the Australian Research Council (ARC); the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva; and the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT). Gemini is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.
Quelle: Institute for Astronomy / University of Hawaii

Tags: Astronomie 

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Sonntag, 16. November 2014 - 11:40 Uhr

Raumfahrt - Trennung von Kirche und Weltraum?

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Separation of Church and Space?
Research by a political science professor shows opinions on space exploration are influenced by a person's religious beliefs.
Whether you believe the Philae probe's landing on a speeding comet is a monumental advance or a colossal waste might depend on your religion, according to a University of Dayton researcher.
Many in the space community see the landing as a critical step in colonizing the solar system, such as NASA Planetary Science Division Director Jim Green who said, "I truly believe that a single-planet species will not survive long. It's our destiny to move off this planet." (see CNET article)
Yet Evangelical Protestants are much surer Jesus will return in the next 40 years than that humans will make significant strides in space exploration, according to research by University of Dayton political science assistant professor Joshua Ambrosius.
"Evangelicals have been hesitant to recognize the discoveries of modern science — from evolutionary origins to climate change," Ambrosius said. "The data show that this overall attitude extends into space."
Ambrosius used data from the General Social Survey and three Pew surveys to compare knowledge, interest and support for space exploration among Catholics, Evangelicals, Mainline Protestants, Jews, Eastern religions and those with no religion.
He found Evangelicals, who account for one-quarter of the U.S. population, are the least knowledgeable, interested and supportive of space exploration, while Jews and members of Eastern traditions were most attentive and supportive.
He also found that while regular church attendance, along with other measures of traditional religious belief like a high view of the authority of the Bible and belief in creationism, exert a negative effect on support for space exploration, clergy support for science exerts a significant positive effect. Evangelicals in particular were twice as likely to recognize the benefits of space exploration if their pastors speak positively about science.
"Efforts to reach Evangelicals must go through the tradition's leadership," Ambrosius said.
But these leaders have to contend with oppositional voices like that of Ken Ham, fundamentalist founder of "Answers in Genesis" and the Creation Museum in Petersburg, Kentucky. Ham has made the argument that search for alien life and habitable planets is pointless because God uniquely created Earth and the life on it, and he has also said the search for alien life is "driven by man's rebellion against God."
Among Catholics, there is more openness to space exploration. The Rev. Jose Gabriel Funes, director of the Vatican Observatory, has said not believing aliens could exist would be "putting limits on the creative freedom of God."
"Within the broader Christian tradition, there are a variety of perspectives about space and extraterrestrial life," Ambrosius said. "The space community can have success with increased outreach to religious groups with the message that space exploration, for means of discovering life-bearing or sustaining planets or otherwise, does not conflict with their faith and is in their — and the entire human race's — best interest."
Ambrosius presented his research this month at the Society for the Scientific Study of Religion conference in Indianapolis.
Quelle: University of Dayton

Tags: Raumfahrt 

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Sonntag, 16. November 2014 - 11:16 Uhr

Raumfahrt - Marine MUOS-3 Start-Vorbereitungen für Januar 2015

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Crews with Lockheed Martin lifting the NAVY’s MUOS-3 satellite for placement in its shipping container fpr delivery to Cape Canaveral, Fla., ahead of a planned January 2015 launch. Photo Credit: Lockheed Martin
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The third in a 5-ship fleet for a next-generation, narrowband tactical military satellite communications system is now at Cape Canaveral Air Force Station in Florida, where crews are making final preparations for a scheduled Jan. 30, 2015 launch. The U.S. NAVY’s latest Mobile User Objective System satellite, identified as MUOS-3, arrived on a C-5 Galaxy transport aircraft via Lockheed Martin’s Sunnyvale, California, facility and nearby Moffett Federal Airfield on Nov. 5, 2014, courtesy of the 60th Air Mobility Wing of Travis Air Force Base. 
“The delivery of MUOS-3 is an important step toward enabling our warfighters to be able to pick up the phone to seamlessly call or transfer data anywhere around the world,” said Iris Bombelyn, vice president of Narrowband Communications at Lockheed Martin. “With the launch of the third satellite in the constellation, to be followed later in 2015 by the fourth, MUOS will be in place to provide pole-to-pole and global, secure communications for the warfighter.”
MUOS operates like a “smart phone cell tower in the sky”, supporting a worldwide, multi-Service population of users in the UHF band, providing increased communications capabilities to smaller terminals while still supporting interoperability with legacy terminals. The new military SATCOM system will, for the first time, give MUOS Wideband Code Division Multiple Access technology users beyond-line-of-sight capability to transmit and receive voice and data using an Internet Protocol-based system, giving users greater mobility, higher data rates and improved operational availability.
MUOS gives military users more communications capability over existing systems, including simultaneous voice, video and data – similar to the capabilities experienced today with smart phones and providing users with ten times more communications capacity.
With MUOS-3 now at its Florida launch site crews from Lockheed are conducting final preparations for liftoff, which will occur on a United Launch Alliance (ULA) Atlas-V rocket from Launch Complex-41 (SLC-41). After completing post-shipment testing technicians will fuel the satellite, then encapsulate it inside the Atlas-V’s 5.4-meter (17.7-foot) bullet-like payload fairing. The encapsulated MUOS-3 satellite will then be integrated on top of ULA’s workhorse rocket for final integrated testing and closeout preparations for launch Jan. 30. The current launch window is 7:42 – 8:26 p.m. EDT.
Flying in its most powerful “heavyweight” 551 configuration, ULA’s Atlas-V will employ the added power of five strap-on Aerojet Rocketdyne solid-fueled boosters to deliver the NAVY’s 15,000 pound MUOS-3 satellite to geosynchronous orbit, more than 22,000 miles above Earth. ULA has launched 50 missions over 12 years on their Atlas-V fleet of rockets, all successfully, but only four of those missions required the 551 configuration; New Horizons to Pluto in 2006, JUNO to Jupiter in 2011, and MUOS-1 and MUOS-2. Once launched a single-engine Centaur upper stage will give MUOS-3 the final push it needs to enter its intended orbit.
Although a total of five MUOS satellites will make up the MUOS fleet, only four will actually be required to put the whole system into action; the fifth and final MUOS to launch in 2016 will serve as an on-orbit spare should any of the first four lose their capabilities.
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Engineers prepare MUOS-3 for acoustic testing. Photo Credit: Lockheed Martin
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Original plans called for the first MUOS to launch by 2010, but budgetary adjustments made in response to the Iraq war led to a two-year delay. MUOS-1 launched on Feb. 24, 2012, followed by MUOS-2 on July 19, 2013, and in the time since both have demonstrated new capabilities, especially in the Arctic, an area previously beyond the coverage of UHF satellites and growing in interest for transportation and natural resources exploration above 65 degrees north latitude. In the past year MUOS successfully connected users near the Arctic poles during independent testing by Lockheed Martin, and during the U.S. Navy’s 2014 Ice Exercise (ICEX) and the U.S. Coast Guard’s Arctic Shield 2014.
The MUOS satellites seek to offer global satellite communications narrowband (64 kbits/sec and lower) connectivity for use by U.S. and allied forces, with an ultra-high frequency range from 300 MHz-3 GHz. When fully functional, it will replace the legacy UHF Follow-On (UFO) satellite network—the first of which was launched back in March 1993—before the latter system reaches the end of its operational service. MUOS will provide new capabilities and enhanced mobility, access, capacity, and quality of service, with particular emphasis upon mobile users, such as aerial and maritime platforms, ground vehicles, and dismounted soldiers.
By operating in the UHF frequency band, which is lower than that used by conventional cellular networks, MUOS will provide U.S. and allied warfighters with the tactical ability to communicate in “disadvantaged” environments, including heavily forested areas where higher-frequency signals would be otherwise impaired. Even troops in buildings with no satellite access are expected to see an increase in communications capability.
The infrastructure to both fly the MUOS satellites and control access of a user’s communications is managed from the ground. Operationally, information flows to the satellites via UHF WCDMA links, and the satellites then relay the information to one of four ground sites located in Hawaii, Virginia, Italy and Australia via a Ka-band feederlink. These facilities identify the destination of the communications and route the information to the appropriate ground site for Ka-band uplink to the satellite and UHF WCDMA downlink to the correct users. MUOS will also provide users access to select Defense Information System Network voice and data services.
Quelle: AS
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Siehe auch: http://www.hjkc.de/_blog/2013/07/19/raumfahrt---us-navy-startet-muos-mobile-user-objective-system-mit-atlas-v-rakete-am-19juli/

Tags: Raumfahrt 

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Sonntag, 16. November 2014 - 10:53 Uhr

Astronomie - Planet-X kann weit jenseits von Neptun lauern

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Out beyond Neptune, the solar system resembles the deep ocean: dark, remote and largely unexplored. To an Earth-bound observer, even the brightest objects, such as Pluto, are 4,000 times as faint as what the human eye can see. An undiscovered planet could easily lurk out there unnoticed, a possible fossil from a time when the giant planets jockeyed for position 4 billion years ago, scattering planets and asteroids in their wake. But even the largest telescopes would struggle to find such a faint spot of light. Most likely, the clues would be entangled in the distorted orbits of faraway ice boulders tumbling around the sun.
Astronomers Chad Trujillo and Scott Sheppard provided a hint about how such a world might reveal itself last March when they announced the discovery of a 450-kilometer-wide dwarf planet just outside the Kuiper belt — the icy debris field past Neptune (SN: 5/3/14, p. 16). 
Their find, designated 2012 VP113, is on a course that loops around the sun in a vastly elongated orbit far from the known planets. It has thousands of neighbors but shares its odd trajectory only with Sedna, another dwarf planet, discovered in 2003.
“They’re kind of in a no-man’s-land,” says Sheppard, of the Carnegie Institution for Science in Washington, D.C. “These objects couldn’t get out there with what we currently know.”
Something had to drag the two dwarf planets from their original, smaller orbits. Except nothing is close or massive enough to take the credit. At least, nothing astronomers are aware of.
The discovery of 2012 VP113 confirmed that Sedna is not a fluke but is possibly the first of a large population of icy bodies distinct from others in the rest of the solar system. So Trujillo and Sheppard continued to poke around the Kuiper belt, and the mystery deepened. They noticed that beyond 150 astronomical units (150 times the distance from the sun to the Earth), 10 previously discovered objects, along with Sedna and 2012 VP113, follow orbits that appear strangely bunched up.
“That immediately piqued our interest,” says Sheppard. Could an unseen planet, a Planet X, be holding the orbits of all these far-out bodies in place?
“The idea’s not crazy,” says David Jewitt, a planetary scientist at the University of California, Los Angeles. “But I think the evidence is slim.” The trail of bread crumbs leading to an undiscovered planet is sparse: just 12 chunks of ice lead the way. But it’s enough to get some researchers wondering about a ninth (or 10th, depending on your attitude regarding Pluto) planet roaming the outer solar system and how it might have arrived there.
Kuiper belt clues
“The exciting thing for me is that 2012 VP113 exists,” says Megan Schwamb, a planetary scientist at Academia Sinica in Taipei, Taiwan. “Whatever put Sedna on its orbit should have put a whole bunch of other objects out there.”
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Dwarf planets Sedna and 2012 VP113 travel well beyond the known planets and the Kuiper belt along highly stretched orbits, which implies something once dragged them out there.
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The enormous, stretched orbits of Sedna and 2012 VP113 are unlike anything else in the solar system. Both are too far from Neptune to feel its effects. And they’re too far from the Oort cloud, the distant shell of ice boulders thought to envelop the solar system. Their trajectories could be a relic of a passing star, or the changing influence of the Milky Way’s gravity as the sun moves around the galaxy — or of a massive planet, long-gone or yet to be detected.
The case for an additional planet got stronger when Trujillo and Sheppard realized that Sedna and 2012 VP113 had something in common with 10 other objects. All the objects beyond 150 astronomical units come closest to the sun, a point known as perihelion, at nearly the same time that they cross the plane of the solar system. There’s no reason for these perihelia to bunch up like that. Billions of years of evolution should have left the perihelia scattered, like the rest of the Kuiper belt — unless something was holding the perihelia in place.
Trujillo and Sheppard estimated that a planet about two to 15 times as massive as Earth, at a distance of  250 astronomical units (about eight times as far from the sun as Neptune) could explain why these 12 perihelia were bunched together. But the astronomers admit that’s not the only possibility. A closer planet as massive as Mars would have the same effect as a Neptune-mass body much farther away.
“A few years ago everyone thought that nothing relevant other than just plain asteroids and comets inhabited that region,” says physicist Carlos de la Fuente Marcos. “Now the observational evidence indicates that probably we were wrong.” He and his brother Raúl, both at the Complutense University of Madrid, took a closer look at the orbits. The brothers claim, in the Sept. 1 Monthly Notices of the Royal Astronomical Society Letters, that not one but two planets are needed to explain the perihelion clustering.
Around the same time, physicist Lorenzo Iorio at the Ministry of Education, Universities and Research in Bari, Italy, offered a different take. He says that the planet proposed by Trujillo and Sheppard, if it exists, must be much farther out — at least twice as far as the original prediction. By looking at gradual changes in the orbits of a few of the known planets, Iorio calculated that a planet twice as massive as Earth must be at least 500 astronomical units from the sun, according to research in the Oct. 11 Monthly Notices of the Royal Astronomical Society Letters.
Others are more cautious. “The outer solar system can be full of all sorts of unseen and interesting things,” Jewitt says, “but the argument ... for a massive perturber is a bit puzzling.” First, 10 of the 12 bodies with peculiar perihelia dive far enough into the Kuiper belt to possibly feel Neptune’s gravity. And, second, he says, 12 objects is a tiny sample — the apparent perihelion clustering may just be an illusion caused by where researchers point their telescopes.
The recent speculation about additional planets has a familiar ring, says Jewitt. In the late 1800s and early 1900s, astronomers relied on apparent hiccups in Neptune’s motion and a handful of comets to kick off a search that eventually led to the discovery of Pluto. “Not much has changed since then,” he says. In fact, musings of a planet beyond Neptune have been around since before anyone knew Neptune existed.
Planet hunters
In 1834, German astronomer Peter Andreas Hansen allegedly suggested to a colleague that two planets were needed to explain oddities in the motion of what was then the farthest known planet, Uranus — oddities that led to the discovery of Neptune in 1846. Two years later, French astronomer Jacques Babinet claimed that Neptune also stumbled along its orbit, hinting that a ninth planet must have been causing Neptune to speed up and slow down as it ran around the sun.
Over the next half century, the search for more planets went in and out of vogue. Like a game of solar system Whac-A-Mole, new predictions popped up after each claimed discovery was trounced. The predictions relied on observations of Neptune as well as a handful of comets that reached their farthest point from the sun at nearly the same distance, a clue that a massive planet was bringing the comets all to the same point before the comets returned to the sun.
In the early 1900s, Boston-born polymath Percival Lowell got into the planet-hunting game. It’s not clear if Lowell was the first person to use the phrase “Planet X,” but he certainly popularized it. Lowell calculated where Planet X should be, based on observations of Uranus and Neptune. Thirteen years after Lowell died in 1916, American astronomer Clyde Tombaugh picked up the torch, using Lowell’s calculations as a guide. Tombaugh’s systematic observations led him to Pluto in 1930, close to where Lowell predicted Planet X would be.
Pluto’s fall from grace started months after its discovery. Unlike the other eight planets, which travel on flat, circular orbits, Pluto speeds through Neptune’s orbit along a stretched, cockeyed trajectory. The diminutive planet didn’t appear massive enough to push the outer planets around. Estimates for Pluto’s mass dwindled until astronomer James Christy discovered Charon, Pluto’s largest moon, in 1978. Christy used the moon’s motion to weigh Pluto and found that the outermost planet had only 0.2 percent of Earth’s mass. If something was tugging on Uranus and Neptune, Pluto was much too small to be the culprit.
NASA’s Voyager 2 spacecraft settled the Planet X question — for a time. When the probe flew past Uranus and Neptune in the 1980s, it gave astronomers better data to revise the masses of the planets. The new data revealed that nothing was pulling on them. Tombaugh finding Pluto where Lowell’s calculations pointed was just a coincidence.
The search for Planet X quieted, never disappearing, but not taken seriously. Planet X became a favorite of the tinfoil-hat crowd, who were convinced that NASA was hiding knowledge of a planet that would either crash into Earth or hurl a barrage of comets our way. The end, as always, was near.
Modern planetary research has been plagued by rough estimates and few objects to study. “What this means,” Schwamb says, “is the observers need to go back to work.” Only a detailed accounting of the darkness beyond Neptune will help researchers figure out if something is there.
If that something exists, it can’t be as massive as Jupiter or Saturn. Kevin Luhman, an astronomer at Penn State, looked for Jupiter doppelgängers in images from NASA’s WISE satellite, a 10-month mission to scan the entire sky twice with an infrared telescope. Massive planets are best seen in infrared light because they’re still cooling off from their formation. Jupiter, for example, radiates more heat than it receives from the sun.
Reporting in the Jan. 20 Astrophysical Journal, Luhman found no evidence for a Jupiter-mass planet within 82,000 astronomical units. Likewise, there’s no sign of something as massive as Saturn out to about a third as far. But Luhman says he can’t rule out a small, rocky planet, which would be too cold for WISE to pick up.
The best bet is to look for reflected sunlight, which is how scientists discovered Pluto and the Kuiper belt. But even large worlds at such enormous distances are extremely dim. If Pluto was twice as far from the sun, it would be one-sixteenth as bright because the sunlight not only has to get out there but also has to come back.
“We would not yet have detected the Earth,” says Jewitt, “if it were more than 600 astronomical units from the sun.” And that’s assuming researchers knew where to look. “That gives you an idea of the darkness of the outer solar system.”
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All known objects beyond 150 times the distance from the sun to Earth make their closest approach to the sun (perihelion) as they pass through the plane of the solar system. Those perihelia should be spread out like Kuiper belt objects. The reason they are not is a mystery.
Sources: C.A. Trujillo and S.S. Sheppard; JPL/Caltech; IAU Minor Planet Center
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Instead of trying to directly observe a planet, researchers are looking for more Kuiper belt objects, whose orbits might bear the gravitational signature of something unseen. Trujillo and Sheppard discovered 2012 VP113 as part of an ongoing effort to scan the sky from Cerro Tololo Inter-American Observatory in Chile. Undoubtedly, more interesting objects will turn up.
Most telescope searches, however, are akin to mapping the universe while staring through a drinking straw. Telescopes see a tiny fraction of the sky, and observatories dole out access just a few days at a time. Sheppard says that it will take them several years to cover just 20 percent of the sky.
Enter the Large Synoptic Survey Telescope, or LSST, an 8.4-meter-wide telescope being built in northern Chile with full operations planned for late 2023. Unlike other telescopes, it will have an enormous field of view and will make a decade-long movie of the sky, perfect for looking for moving points of light.
Lynne Jones, an astronomer at the University of Washington in Seattle, says the LSST could find 20,000 to 40,000 more bodies in the Kuiper belt. With about 20 times as many Kuiper belt objects in hand, astronomers should be able to see if there are more objects with bizarre orbits and determine if the bunching of perihelia is real or just an artifact of having found only a few.
Plus, says Jones, LSST could detect an Earth-sized planet out to between 300 and 500 astronomical units, depending on how reflective its surface is.
For planetary scientists, if a remote Planet X exists the question is: How do you form a planet that far from the sun? Renu Malhotra, a planetary scientist at the University of Arizona in Tucson, says the problem is time. At that distance, the planet building materials would have been smeared over a ring several hundred billion kilometers around. “To make a planet the size of the Earth,” says Malhotra, “could take longer than the age of the solar system.” The only solution, she says, is to steal the planet from somewhere else.
Uranus and Neptune are the most likely thieves, pilfering planets from the space between their orbits. Malhotra says that a close encounter with either of those giants could slingshot an Earth-sized ball of rock to well beyond the Kuiper belt.
Planet X might also be extrasolar, says planetary scientist Rodney Gomes of the National Observatory in Rio de Janeiro. The sun was born in a nebula along with several thousand other stars, and many of those probably had planets of their own. As stars jostled each other, planets could have been torn away from one star and captured by the gravity of another. Perhaps Planet X is just the result of a brief game of interstellar catch.
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The Large Synoptic Survey Telescope in Chile, illustrated here, will make a 10-year-long movie of the night sky starting in 2023.
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“The jury’s still out on whether you need to have a planet there or not,” Schwamb says. A close encounter with a passing star could have lured Sedna and 2012 VP113 away from their siblings, like an astronomical pied piper. Stellar flybys are rare, however, and the star must pass close enough for the two dwarf planets to notice but not so close that it disrupts the entire Kuiper belt and possibly the outer planets.
The odds go up if the star is a relative, born in the same nebula as the sun. In addition to tossing planets around, stellar siblings could have tugged on the debris swirling around the sun. The distorted orbits would have frozen in place after the sun’s brothers and sisters drifted away.
For 168 years, the lure of planets hiding beyond Neptune has never faded. The remoteness of the outer solar system, Jewitt says, “leaves open the door to all sorts of wild speculation.”
The hunt for Planet X “is one of those things that’s very high risk,” Luhman says, “but if it was found, it would be a huge discovery.” Astronomers have discovered more than 1,800 planets orbiting other stars, and yet our own backyard is still largely a mystery. “We haven’t explored all of the solar system yet,” Sheppard says, “so people always want to believe that there’s something else out there.”
Quelle: ScienceNews

Tags: Astronomie 

2013 Views

Samstag, 15. November 2014 - 15:54 Uhr

Raumfahrt - Start von Long March-2C Rakete mit Yaogan-23 Satelliten

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China has launched the Yaogan-23 remote sensing satellite into scheduled orbit from the Taiyuan Satellite Launch Center in North China’s Shanxi province. 
The satellite will mainly be used for scientific experiments, natural resource surveys, crop yield estimates and disaster relief. It was carried by a Long March-2C rocket, marking the 198th mission for the Long March rocket family.

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A Long March-2C carrier rocket carrying the Yaogan-23 remote sensing satellite blasts off from the launch pad at the Taiyuan Satellite Launch Center in Taiyuan, capital of north China's Shanxi Province, Nov. 14, 2014. The satellite,which was launched at 2:53 a.m. Saturday, will be used for scientific experiments, natural resource surveying, estimating crop yields and disaster relief.The launch marks the 198th flight of the Long March rocket series.
Quelle:Xinhua

Tags: Raumfahrt 

1966 Views

Samstag, 15. November 2014 - 15:25 Uhr

Mars-Chroniken - Gibt es organisches Material auf dem Mars?

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Chlormethan auf dem „Roten Planeten“ stammt möglicherweise aus dem Marsboden – Meteoriten lieferten vermutlich den darin enthaltenen Kohlenstoff und Wasserstoff

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Foto: Bastian Baecker (Universität Heidelberg / Max-Planck-Institut für Chemie, Mainz), Luigi Folco (Universität Pisa) und Carole Cordier (Universität Grenoble)
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Aus dem Rasterelektronenmikroskop stammende Aufnahmen von einem Mikrometeoriten. Diese Mikrometeoriten wurden auf der Erde (Antarktis) gesammelt. Es wird angenommen, dass jedes Jahr eine relativ große Menge an Mikrometeoriten mit ähnlicher Zusammensetzung auf den Mars fällt. Ein Teil des darin enthaltenen organischen Materials könnte beim Erhitzen in Chlormethan umgewandelt werden.
Das vor kurzem mit dem NASA-Mobil „Curiosity“ auf dem Mars entdeckte organische Material könnte einen anderen Ursprung haben als von der Erde mitgebrachte „Verunreinigungen“, wie Wissenschaftler bislang gedacht haben: Ein deutsch-britisches Forscherteam um den Geowissenschaftler Prof. Dr. Frank Keppler von der Universität Heidelberg geht davon aus, dass die auf dem „Roten Planeten“ aufgefundene gasförmige chlororganische Verbindung – das Chlormethan – möglicherweise aus dem Boden des Mars‘ stammt und der darin enthaltene Kohlenstoff und Wasserstoff vermutlich durch einschlagendes Meteoritengestein geliefert wurde. Gestützt wird diese Annahme durch Isotopenmessungen, mit denen die Wissenschaftler die Experimente von „Curiosity“ nachvollzogen haben. Untersucht wurden dazu die Proben eines 4,6 Milliarden Jahre alten Meteoriten, der 1969 in Australien auf der Erde eingeschlagen ist. Die Forschungsergebnisse wurden in den „Scientific Reports“ veröffentlicht.
Die Frage, ob organisches Material auf dem Mars existiert und damit eine der Voraussetzungen für Leben auf diesem Planeten gegeben ist, beschäftigt die Wissenschaft schon lange Zeit. Das NASA-Mobil „Curiosity“, das Mitte 2012 auf dem Mars gelandet ist, führt dazu Untersuchungen auf dem Marsboden durch. Bei Experimenten mit dem Erhitzen von Bodenproben haben sich tatsächlich einfache organische Moleküle gebildet, wie die Analyse mit einem „Curiosity“-Messinstrument gezeigt hat. Dazu gehört auch Chlormethan, das Kohlenstoff-, Wasserstoff- und Chloratome enthält, wie Prof. Keppler erläutert. Nach Meinung der NASA-Experten entstand diese Verbindung möglicherweise jedoch während der Experimente in einer Reaktion von Perchloraten aus dem Marsboden mit einem chemischen Stoff von Bord der Sonde. Obwohl das Chlor des Chlormethans damit vom Mars selbst stammt, könnten Kohlenstoff und Wasserstoff durch „Curiosity“ zum Mars gelangt sein. Derartiges organisches Material ist bereits in früheren Experimenten während der Viking-Mission 1976 entdeckt worden. Diese Entdeckung wurde jedoch ebenfalls mit „Verunreinigungen“ von der Erde begründet.
Das deutsch-britische Wissenschaftlerteam um Prof. Keppler ist in diesem Zusammenhang der Frage nachgegangen, ob es nicht auch eine andere Erklärung für den Nachweis von Chlormethan auf dem Mars geben könnte. Ihre Annahme: Die gasförmige chlororganische Verbindung kommt tatsächlich im Marsboden vor, wobei der darin enthaltene Kohlenstoff und Wasserstoff von Meteoriten stammt. Um diese These zu erhärten, haben die Forscher Proben eines 4,6 Milliarden Jahre alten Meteoriten untersucht, der 1969 nahe der australischen Stadt Murchison auf der Erde eingeschlagen ist. Nach Angaben von Prof. Keppler enthält dieses meteoritische Material zwei Prozent Kohlenstoff. Astronomen gehen davon aus, dass jedes Jahr eine relativ große Menge an Mikrometeoriten mit ähnlicher Zusammensetzung auf den Mars fällt.
Als die Wissenschaftler um Frank Keppler das meteoritische Material aus Murchison in Gegenwart von Chlor erhitzten, konnten sie Chlormethan nachweisen. „Das Verhältnis aus schwerem und leichtem Kohlenstoff und Wasserstoff, der sogenannte isotopische Fingerabdruck dieses Gases, zeigt eindeutig, dass das organische Material einen extraterrestrischen Ursprung hat“, so Prof. Keppler. Die Wissenschaftler haben die Ergebnisse dieser Isotopenmessungen auf die Bodenbedingungen auf dem Mars übertragen, wo vergleichbar zusammengesetztes Meteoritengestein zu finden ist. „Demnach könnte das Chlormethan, das bei zwei Marsmissionen gefunden wurde, im Marsboden vorkommen. Kohlenstoff und Wasserstoff hätten dagegen ihren Ursprung in den Mikrometeoriten, die auf den Mars niederregnen“, erläutert Prof. Keppler. „Ausgeschlossen wäre aber auch nicht, dass lebende Organismen, die es eventuell vor längerer Zeit auf dem Planeten gegeben hat, zu einem Teil dieses organischen Materials beigetragen haben.“ Nach den Worten des Heidelberger Wissenschaftlers könnte der isotopische Fingerabdruck des Chlormethans auch bei künftigen Weltraummissionen Hinweise darauf geben, ob das organische Material vom Mars selbst stammt, durch Meteoriten dort hingelangt ist oder auf Verunreinigungen durch Sonden von der Erde zurückgeht.
Frank Keppler leitet die Forschungsgruppe Biogeochemie am Institut für Geowissenschaften der Universität Heidelberg. Neben den Wissenschaftlern der Ruperto Carola haben an den Untersuchungen auch Experten des Max-Planck-Instituts für Chemie in Mainz sowie der School of Biological Sciences an der Queen‘s University Belfast mitgewirkt.
Quelle: Universität Heidelberg.

Tags: Mars-Chroniken 

1949 Views

Samstag, 15. November 2014 - 15:15 Uhr

UFO-Forschung - IFO-Universität: Linsenwolken

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Amazing! So beschreiben Facebook-Poster dieses Foto, aufgenommen in der Sierra Nevada.
Ist das ein UFO? Auf den ersten Blick könnte man es meinen. Die Begeisterung in der spanischen Sierra Nevada, wo man jetzt schon Skifahren kann, war jedenfalls groß. Dieses Foto hat eine Webcam am Donnerstag, dem 13. November 2014 aufgenommen. Es zeigt eine seltsame, aber spektakuläre Wolke hinter dem Bergkamm. Dass sie genau dort auftrat, ist kein Zufall. In der Fachsprache wird dieses runde bis spiralförmige Wolkenphänomen "Lenticularis" genannt.
Quelle: oe24

Tags: UFO-Forschung 

2227 Views

Samstag, 15. November 2014 - 11:00 Uhr

Astronomie - Aurora-Alarm

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Aurora-Alarm für 15.11.2014

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Quelle: Spaceweather


Tags: Astronomie 

2015 Views

Freitag, 14. November 2014 - 22:25 Uhr

Planet Erde - Mt. Taranaki in Egmont National Parkim Blick von Landsat-8

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In July 2014, Landsat 8 captured the isolated island of protected forest around New Zealand’s Mt. Taranaki in Egmont National Park surrounded by once-forested pasturelands.
Image Credit: NASA/USGS
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Efforts to conserve parks and protected areas around the world are being aided by Earth observations from space-based sensors operated by NASA and other space agencies as well as commercial providers. A new book released this week highlights how the view from space is being used to protect some of the world’s most interesting, changing, and threatened places.
“Sanctuary: Exploring the World’s Protected Areas from Space,” published by the Institute for Global Environmental Strategies (Arlington, Virginia) with support from NASA, debuted at the 2014 World Parks Congress in Sydney, Australia. The once-a-decade meeting is sponsored by the International Union for Conservation of Nature, the world’s largest global environmental organization founded in 1948.
Uniting satellite imagery with nature photography, descriptions of conservation projects, and comments from park leaders and conservationists, “Sanctuary” illustrates the contributions remote sensing is making to reaching conservation goals, responding to climate change, and improving human health and well-being.
In the book’s foreword, NASA Administrator Charles Bolden writes, “NASA and numerous other space agency partners from around the globe have used this view from space to make incredible scientific advances in our understanding of how our planet works. As a result, we can now better gauge the impact of human activity on our environment and measure how and why our atmosphere, oceans, and land are changing.
"As a former astronaut who has looked upon our beautiful planet from space, I hope that we can advance the use of space-based remote sensing and other geospatial tools to study, understand, and improve the management of the world’s parks and protected areas as well as the precious biodiversity that thrives within their borders.”
There are about 209,000 protected areas worldwide, covering 14 percent of the planet’s land and 11 percent of coastal areas, as well as 3.6 percent of the world’s oceans. Protected areas featured in “Sanctuary” include Hawaii’s Papaphanaumokuakea Marine National Monument, New Zealand’s Mount Egmont National Park, the weaving waterways of the Sundarbans in Bangladesh, and the Great Barrier Reef in Australia.
One type of conservation effort highlighted in the book is the growing trend of connecting areas to protect migrating species such as the pronghorn, which migrates the longest distance of any terrestrial animal in the United States: more than 350 miles. Jonathan B. Jarvis, director of the U.S. National Park Service, states: “For the first time in my nearly 40 years of work in the National Park Service, the four U.S. land management agencies are working together, applying the newest geospatial technologies to identify and protect critical corridors of connectivity between protected areas.”
Space-based Earth observations are also used as inputs into advanced computer models to help identify and predict environmental changes. With this information the conservation community can develop adaptation strategies and prepare for impacts such as disrupted migrations or increased wildfires, floods, and drought. By integrating climate model forecasts with an understanding of species habitat ranges, scientists can estimate where species may live in the future, where today’s protected areas might suffer stress, or where future protected areas may need to be located.
For over 10 years, NASA’s basic research and applied conservation programs have advanced our understanding of global change impacts within and around protected areas. Ongoing projects include assessing coral reef health, investigating the vulnerability of U.S. National Parks to climate change, and establishing marine biodiversity observation networks. NASA’s Earth science program has made numerous satellite-derived data products freely available to the research and applications community to support conservation around the world.
Imagery and content in “Sanctuary” were provided by NASA’s Jet Propulsion Laboratory, NASA’s Goddard Space Flight Center, the National Oceanic and Atmospheric Administration (NOAA), DigitalGlobe Corporation, the European Space Agency, Conservation International, the World Wildlife Fund, and other organizations.
Quelle: NASA

Tags: Planet Erde 

2091 Views


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