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Sonntag, 8. Juni 2014 - 22:00 Uhr

Astronomie - Bei einer weit, weit entfernten Galaxie: Astronomen entdecken Alte Super-Erde in unserer galaktischen Nachbarschaft

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Artistic representation of the recently-discovered potentially habitable world Kapteyn b, with the globular cluster Omega Centauri in the background. It is believed that the Omega Centauri is the remaining core of a dwarf galaxy that merged with our own galaxy billions of years ago bringing Kapteyn’s star along. Credit/Caption: PHL @ UPR Arecibo, Aladin Sky Atlas.

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A new generation of ground and space-based observatories that have come online during the last decade, has helped to kick exoplanet research into high gear with new discoveries of exoplanets today announced almost at a weekly basis. Following on the heels of the unexpected discovery of a heavyweight ‘Mega-Earth’, that was reported in a previous AmericaSpace article earlier this week, an international team of astronomers has announced the discovery of two nearby ‘Super-Earth’ worlds orbiting an 11-billion year-old red sub-dwarf star at a distance of 12.7 light-years away. More interestingly, one of the newly discovered exoplanets is found to lie inside the star’s habitable zone, making it the oldest possibly habitable exoplanet known to date.

Traditionally being overlooked by astronomers in their search for life in the Universe, red dwarfs are by far the biggest stellar population in the Milky Way, accounting for approximately 75 percent of the galaxy’s total number of stars. Much smaller in size and less luminous and massive than the Sun, they burn their hydrogen fuel at a very slow rate, which allows them to have lifespans of up to many trillions of years. One of the thousands such stars that are located in the Sun’s wider neighborhood, is Kapteyn’s Star, a red sub-dwarf that lies approximately 12.7 light years away in the direction of the southern constellation of Pictor. An otherwise dim and inconspicuous object, Kapteyn’s Star soon became famous following its discovery in 1897 because of its observed very high proper motion across the sky of 8.7 arcseconds per year, making it the highest of any known stellar object at the time, until the discovery of Barnard’s Star in 1916. With a mass and size approximately one-third that of the Sun and an abundance of heavy elements less than 10 percent solar, Kapteyn’s Star was, as most red dwarfs, historically seen as a poor candidate for hosting any planets and habitable environments.

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Kapteyn’s star and its planets likely come from a dwarf galaxy now merged with the Milky Way. Bottom right panel shows characteristic streams of stars resulting from such a galactic merging event. Image Credit/Caption: Victor H. Robles, James S. Bullocks, Miguel Rocha, from UC-Irvine and Joel Primack from UC-Santa Cruz

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The superior sensitivity of the latest generation of ground-based instruments, has allowed astronomers to discover a wealth of exoplanets (most of them in multi-planetary systems) around red dwarfs, while overturning our conventional notions and expectations regarding planetary formation and evolution processes around metal-poor stars. In a new study that has been accepted for publication in the Monthly Notices of the Royal Astronomical Society, a team of researchers led by Dr Guillem Anglada-Escudé, a Lecturer at Queen Mary University of London’s School of Physics and Astronomy, have announced the discovery of two ‘Super-Earths’ orbiting Kapteyn’s Star, making them some of the oldest known extrasolar worlds to date.

The new discoveries were made with the help of the radial velocity method, which looks for the periodic shifts of certain spectral lines in a star’s light that are caused by the gravitational tug of invisible planets which orbit the star. The research team took a series of radial velocity measurements of Kapteyn’s Star’s light between May and December 2013 using the High Accuracy Radial Velocity Planet Searcher, or HARPS, a high-resolution spectrograph mounted on ESO’s 3.6m telescope at the La Silla Observatory in Chile, which clearly revealed the presence of two distinct signals, indicating the presence of two high-mass planets. In order to confirm these findings, the team combined its observations with a series of previous ones that had been made with HARPS, as well as with the more advanced High Resolution Echelle Spectrometer, or HIRES, at the Keck Observatory in Hawaii and the Planet Finding Spectrograph, or PFS, at the Las Campanas Observatory in Chile. “We were surprised to find planets orbiting Kapteyn’s star”, says Dr Anglada-Escudé. “Previous data showed some moderate excess of variability, so we were looking for very short period planets when the new signals showed up loud and clear.”

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Comparison of the relative size of the orbits and the planets of Kapteyn’s Star and the inner planets of our Solar System. Planets are magnified x100 and stars x10 with respect to the orbit scale for clarity. Image Credit/ Caption: PHL @ UPR Arecibo

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Even though the radial velocity method can only give some rough measurements of an exoplanet’s properties like minimum mass and orbital period, it nevertheless allows astronomers to make some educated guesses regarding the planet’s overall structure. The observations by Dr Anglada-Escudé’s team, have shown that both of the newly discovered planets are ‘Super-Earth’s, which are worlds whose masses can be up to 10 times that of the Earth. More importantly, the first one, called Kapteyn b, was found to lie inside its star habitable zone where conditions are just right for liquid water to exist on its surface. “The planet known as Kapteyn b has a mass at least five times that of Earth’s and orbits the star every 48.6 days – this is an orbit where it might have liquid water”, says Dr. Mikko Tuomi, a Research Fellow at the University of Hertfordshire’s Centre for Astrophysics Research, in the UK, and co-author of the study. The second planet, called Kapteyn c, was found to have a mass at least seven times that of Earth and an orbital period of 121.5 days which puts it well outside of the star’s habitable zone. “We think it’s too cold to support liquid water” adds Tuomi.

Such orbital periods would put both of Kapteyn’s star’s planets well inside the orbit of Venus in our Solar System, something that would surely make them as inhospitable as Earth’s ‘twin sister’. Yet, due to the substantially lower luminosity of red dwarfs compared to that of the Sun, the habitable zones around these stars are found much closer in than that of our own Solar System. For many astronomers, the extreme environments around many red dwarfs during their early years of development, characterized by the eruptions of gigantic coronal mass ejections, high variability and a constant stream of lethal X-ray and ultraviolet radiation, make these stars unsuitable for life. Yet, a growing number of studies in recent years, have suggested that red dwarfs may ultimately be some of the best types of stars to search for exoplanets and habitability. As detailed in a previous AmericaSpace article, a past statistical analysis that was done by a research team led by Dr. Mikko Tuomi, had concluded that habitable ‘Super-Earths’ may be rather common around red dwarf stars. In addition, further studies had shown that the conditions needed to sustain life, could be found well beyond a star’s habitable zone, making otherwise inhospitable worlds more conducive to life. “Finding a stable planetary system with a potentially habitable planet orbiting one of the very nearest stars in the sky is mind-blowing”, says Pamela Arriagada, a Postdoctoral Fellow at the Carnegie Institution’s Department of Terrestrial Magnetism in Washington and member of Anglada-Escudé’s team. “This is one more piece of evidence that nearly all stars have planets, and that potentially habitable planets in our Galaxy are as common as grains of sand on a beach.”

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Artistic representation of the potentially habitable exoplanet Kapteyn b as compared with Earth. Kapteyn b is represented here as an old and cold ocean planet with a network of channels of flowing water under a thin cloud cover. The relative size of the planet in the figure assumes a rocky composition but could be larger for a ice/gas composition. Image Credit/Caption: PHL @ UPR Arecibo

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Another very interesting aspect of Kapteyn’s Star, besides the prospect of habitability of its newly discovered exoplanets, is the origin of the star itself. Astrometric studies have found that it shares the same retrograde motion around the center of the Milky Way with a few dozen other stars, which are collectively called the Kapteyn group. In addition, these stars are not orbiting the galactic center inside the Milky Way’s spiral arms like the Sun, but they originate from the spherical Galactic halo that surrounds the Milky Way’s main disk, while briefly intersecting it in their long, elliptical orbits around the center. Furthermore, comprehensive spectroscopic analysis of most of the Kapteyn group’s stellar population has revealed the it shares the same elemental abundance with many of the millions of old stars that comprise the 12-billion-year-old Omega Centauri, the largest globular cluster in the galaxy located 15,800 light-years away in the constellation of Centaurus.

Astronomers have long regarded Omega Centauri as being the remains of a dwarf galaxy that collided with and was absorbed by the Milky Way in the distant past. Computer simulations coupled with the astrometric and chemical measurements of the Kapteyn group’s stars, have suggested that the latter’s current orbits have been the result of this ancient collision. “The age of Kapteyn star can be inferred from its membership to the Galactic halo and peculiar element abundances”, writes Dr. Anglada-Escudé’s team in its study. “The current hierarchical Milky Way formation scenario suggests that streams of halo stars were originated as tidal debris from satellite dwarf galaxies being engulfed by the early Milky Way. This scenario is supported by the age estimations of the stars in the inner halo (10–12 billion years old) and globular clusters. [Previous studies] established the existence of such high-velocity, metal-poor moving groups in the solar neighborhood. Kapteyn’s star is the prototype member of one of these groups…The origin of Kapteyn’s star within a merging dwarf-galaxy sets its most likely age around the young halo’s one (> 10 billion years) and should not be older than 13.7 billion years, which is the current estimate of the age of the Universe”.

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The Omega Centauri globular cluster, photographed by the VLT Survey Telescope that was recently installed at ESO’s Paranal Observatory in Chile. Previous studies have indicated that the globular cluster is Kapteyn’s Star place of origin. Image Credit: ESO/INAF-VST/OmegaCAM. Acknowledgement: A. Grado/INAF-Capodimonte Observatory

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Since Omega Centauri is thought to be Kapteyn’s star place of origin, scientists estimate that its planets must be approximately 11.5 to 12 billion years old, thus making Kapteyn b not only the oldest known possibly habitable exoplanet to date, but along with Kapteyn c, the first that might have originated from another galaxy, outside of the Milky Way as well. “It does make you wonder what kind of life could have evolved on those planets over such a long time”, says Anglada-Escudé. “This discovery is very exciting”, adds Dr. Richard Nelson, Professor of Astronomy and Mathematics at Queen Mary University of London’s School of Physics and Astronomy, while commenting on the recent findings. “It suggests that many potentially habitable worlds will be found in the next years around nearby stars by ground-based and space-based observatories, such as PLATO. Until we have detected a larger number of them, the properties and possible habitability of the near-most planetary systems will remain mysterious.”

With the launch of ESA’s PLATO observatory and the joint NASA/ESA James Webb Space Telescope, scheduled to take place within the next few years, the next generation of space-based instruments will open their electronic eyes to the Cosmos, aiming to solve these long-standing mysteries.

What will they find?

Quelle: AS


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Sonntag, 8. Juni 2014 - 18:30 Uhr

Raumfahrt - Boeing baut ersten vollelektrischen Satelliten

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An electric ion thruster is tested at NASA’s Glenn Research Center in Cleveland. Boeing has developed the first fully electric commercial satellite powered by a xenon-ion propulsion system, which works by charging heavy gas molecules and firing them at extremely high speeds. Nasa Photo

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Boeing is on track to complete the world’s first fully electric commercial satellite, an innovation that will save telecommunications companies tens of millions of dollars per launch.

Electric satellites are only slightly cheaper to produce than traditional satellites but weigh significantly less, allowing launch providers to stack two satellites into one space pod and cut launch costs in half.

The immediate benefits of these smaller electric satellites are cheaper launches, but analysts say lighter propulsion systems will ultimately allow manufactures to build much more powerful satellites in the future.

 

Traditional satellites operate using hybrid technology. After a satellite is launched into space, it uses a liquid, chemical fuel-powered thruster to reach its final orbit position. Once in place, the satellite relies on solar-powered ion thrusters to tweak its position. Solar panels also power the satellite’s sensors.

But liquid-fuel rocket thrusters are very heavy, making up about a third of a satellite’s total weight. Fully electric satellites have no liquid fuel and rely solely on electric ion propulsion to reach orbit.

 

“It makes it very affordable for us to put a satellite into orbit,” said Ken Betaharon, chief technology officer at Asia Broadcast Satellite.

ABS has purchased the first of two fully electric 702SP satellites that Boeing expects to finish building later this year before sending them to Cape Canaveral, where Hawthorne-based SpaceX will stack and launch them on its Falcon 9 rocket in early 2015.

Betaharon said it costs ABS $175 million to $180 million to build, insure, and launch an electric satellite, much less than the $250 million to $275 million it would have cost for one with hybrid technology.

 

So why aren’t all satellite companies switching to electric?

The technology is new and relatively unproven, which means companies are skittish about using it to power their very expensive spacecraft.

Electric propulsion is also much slower than liquid fuel. It takes two to three weeks for a gas-powered satellite to reach its orbit compared to four to five months with ion propulsion.

“With electric propulsion, there is no free lunch,” Betaharon said. “You save a lot of the launch cost but you pay for the time it takes to get the satellite into geostationary orbit.”

 

Betaharon said that the conventional wisdom used to be that larger satellites brought down the per-sensor cost because of the economy of scale. The emergence of fully electric, stackable satellites has pushed the bigger-is-better logic “right out the window,” Betaharon said.

With six satellites in orbit, ABS is a relatively small satellite service provider that is more sensitive to cost than larger providers that may have reservations about fully electric propulsion, which has yet to prove itself, according to Roger Rusch, who runs the Palos Verdes Peninsula-based satellite industry consulting firm TelAstra Inc.

 

Rusch said satellite operators are starting to ask about all-electric designs but most aren’t ready to put their eggs in an untested basket. This is especially true in the case of fully electric satellite propulsion, which was attempted in the 1970s and ’80s with spotty results.

“When you have a new technology that’s had problems in the past, companies are reluctant to rely upon it exclusively,” Rusch said. “Companies like to have the confidence of the proven technology even if it’s not as efficient. If you have something and it fails and there’s no backup whatsoever, you’re going to be in difficulty right away.”

 

For companies like ABS, the discount afforded by going all-electric is worth the risk, and larger companies will likely follow, since the lighter technology will allow companies to build heavier, more complex satellites.

“Ultimately, if someone’s got a concept where they need to build a very big satellite that they wouldn’t have been able to launch before because it would have been too heavy, now they can do that,” said Tim Farrar, president of satellite consulting firm TMF Associates.

Until ion propulsion technology improves, however, it will continue to take months for all-electric satellites to arrive in orbit.

 

“It’s weighing the savings and urgency,” Farrar said. “If you’ve got to launch your satellite before the World Cup, you’re not going to be able to do it.”

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Engineers work on the world's first fully electric satellite at Boeing's satellite factory in El Segundo. The first launch is slated for later this year.

Quelle: The Daily Breeze


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Sonntag, 8. Juni 2014 - 18:15 Uhr

Raumfahrt - ISRO plant Experimental Mission GSLV Mark III im Juli / August

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Experimental mission of GSLV Mark III in July/ August

Indian Space Research Organisation is likely to launch its experimental mission of GSLV Mark III with passive cryogenic stage in the last week of July or the first week of August, a senior official said today.

"The experimental mission of GSLV Mark III would be carried out in the last week of July or in the first week of August," GSLV Project Director K Sivan told PTI over phone.

Explaining the features of GSLV Mark III, he said that unlike the earlier version of GSLV, GSLV Mark III would be able to carry a payload of four tonne.

Observing that the works towards developing the cryogenic stage was "going on right now," he said ISRO would proceed with the solid and liquid stages during the experimental mission.

Detailing on the mission, he said the launch would also benefit ISRO in testing the module it has developed for its ambitious human mission.

"The module would be tested, after the liquid fuel stage is completed. The module is to test the safe landing of human after their trip to the space," he said.

It was in January this year ISRO successfully launched its first indigenous cryogenic engine on GSLV, whose expertise it was long managing to master.

After the successful launch of GSLV, ISRO is focusing on the development of GSLV Mark III, which if succeeded is likely to bring millions of dollars as foreign exchange.

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Quelle: Business Standard


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Sonntag, 8. Juni 2014 - 15:30 Uhr

UFO-Forschung - UFO-Absturz bei Rendlesham Forest? - Teil-4

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The lighthouse at Orford Ness
I have just about reached a certain level of frustration with some of the more ridiculous arguments defending the Rendlesham case. In the recent UFO documentary ,“Secret history of UFOs”, retired Colonel Charles Halt once again denied he could be confused by the lighthouse,
There was a distant light house out of Orford Ness, which I was very familiar with....and it wasn’t the lighthouse.1
To follow this up, Leslie Kean added:
It is just absurd to imagine that these gentlemen... you know...would not know what the light house beam looked like and would come up with stories about UFOs. I mean there are people out there that will say anything to make a UFO case go away....2
Kean’s statement is based not on the evidence but on what Halt told her and what she wants to believe. The actual evidence demonstrates that Halt was not as knowledgeable about the lighthouse as he and Kean claim.
The evidence
Colonel Halt has repeatedly stated in interviews that he was not looking at the lighthouse and it was off to the right of his flashing light that he describes on the tape and in his memo:
First, the lighthouse was visible the whole time. It was readily apparent, and it was 30 to 40 degrees off to our right. If you were standing in the forest where we stood, at the supposed landing site or whatever you want to call it, you could see the farmer’s house directly in front of us. The lighthouse was 30 to 35 degrees off to the right, and the object was close to the farmer’s house and moving from there to the left, through the trees.3
How does this claim compare to the actual evidence from 1980? The recording of Halt and his team’s observations that night gave a bearing for the flashing light:
Now it’s stopped... Now it’s coming up... Hold on. There we go... about approximately four foot off the ground, at a compass heading of 110 degrees.4
Based on what Halt has continuously stated to those who want to believe him, the lighthouse should have been at a bearing of 140-150 degrees. We can see on a map that the lighthouse was on a true bearing of 95 degrees (yellow line). Clearly, it was not at a bearing 30-40 degrees to the right if the 110 degree bearing is accurate. Perhaps the bearing on the tape was significantly off. That would mean the bearing to the UFO was about 65 degrees from the lighthouse, which puts the bearing to the UFO in the direction well to the left of the farmhouse and towards the town of Sudbourne (red line).

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The evidence from the Halt tape refutes this direction:
2:44. We’re at the far side of the farmer’s...the second farmer’s field and made sighting again about 110 degrees. This looks like it’s clear off to the coast. It’s right on the horizon. Moves about a bit and flashes from time to time. Still steady or red in colour... 5
Instead of heading towards Sudbourne, to the ENE, Halt took his team almost due east into the field beyond the farm house. Looking at Ian Ridpath’s image of the farm house from where Halt stated he was standing (see right), one can see that the Orford Ness lighthouse is just visible over the ridge line.
The difference between the bearing on the tape and the actual bearing to the lighthouse can be explained by the inaccuracies involved with making such a measurement on an intermittent point source in the dark. Considering this, it seems that a difference of 15 degrees is within the margin for error.
Why would Halt think the lighthouse was to the right? The source of this confusion was first publicly identified by James Easton. At a bearing of about 118 degrees was the Shipwash lightship. (I got the location used on the previous page from http://www.wrecksite.eu/refPosView.aspx?126471 - 52 deg 1.734 min N and 1 deg 38.237 min E). This position may be inaccurate (other sources give locations in slightly different positions) but it serves as a an approximate location for evaluation. The lightship had a flashing white light on it and was over twenty degrees to the right of the lighthouse. Assuming a reasonable margin for error in Halt’s memory, it is reasonable to conclude that he had confused the lightship for the lighthouse.


Finally, we have the obvious description of the flashing light on the tape syncing up with the rotation rate of the Orford Ness lighthouse. This was demonstrated back in 1983 by Chuck DeCaro of CNN and was also presented on the Secret History of UFOs program. It is the most important evidence that this UFO was the lighthouse.
More denial
The other players in the Rendlesham affair are James Penniston and John Burroughs. They also have denied for many years that they could not confuse the lighthouse for their UFO. In 1998, we learned that they were not being completely honest. In 1980, Colonel Halt collected statements from all of the individuals involved that night, including a third team member and the supervisory personnel. James Easton discovered these statements in the case file and published them. What became clear, after reading them, was that all three personnel were confused by the lighthouse. They stumbled through the woods chasing some lights in the distance. One of these was a flashing light, which they pursued for some time before realizing it was just the lighthouse. This was something they had claimed they knew all about and could never be confused by. It appears that these claims, made years later, were less than accurate.
The excuse has been made that these principal witnesses simply lied in their official statements about this lighthouse pursuit. However, the statements of Master Sergeant Chandler and Lt. Buran, who had no reason to lie, confirm that this is what was reported to them on the radio. The truth of the matter is that these individuals, like Halt, have convinced themselves, and others, that they could not be fooled by the lighthouse when they actually were.
Conclusion
When Kean states this it is absurd that AF personnel could mistake the lighthouse for a UFO, she is either ignoring the evidence or simply hoping the viewer would not be exposed to it. The producers of the program, “Secret History of UFOs” submarined her claim by showing the lighthouse and playing the tape. That evidence is very clear that they were confused by the lighthouse and it played a major role in this case on both nights.

Quelle: SUNlite 5/2012


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Sonntag, 8. Juni 2014 - 15:00 Uhr

UFO-Forschung - UFO-Absturz bei Roswell 1947 ? Teil-19

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Is it all about book sales?
The CIA’s former Entertainment Liaison Officer (really....that was his position!), Charles Brandon, announced that he has seen the secret Roswell case files in a box marked “Roswell”. However, he will not reveal what was in there except that a craft and bodies were recovered. Color me skeptical but I suspect this is a ploy by Brandon to promote the release of his new book. Rumors and claims of seeing top secret documents, bodies, alien metals, and such have been around for decades. Many crashologists considered the story to be a bogus claim and were very skeptical of his statements. If only they would show the same degree of skepticism towards some of the other claims/stories about Roswell. The CIA would later publicly respond stating they did not know what Brandon was talking about.
Burnt ground and an Air Force button
On “Chasing UFOs”, Frank Kimbler presented his LANDSAT images of the area, which supposedly shows a controlled burn of the crash site. He gave no time frame for the burn and I doubt that it happened right after the Roswell incident. If the materials were as indestructible as claimed, I doubt a fire would eliminate, or significantly alter, the evidence. Another interesting point is the “burn area” goes from WNW to ESE. This is not what Jesse Marcel Sr. stated in his interviews. He stated the debris field went from NE to SW.
Kimbler also showed the team an enclosed box displaying the bits of debris he found over the years. If one recalls, back in a July of 2011 interview with Openminds radio (time 00:55:47-00:56:15), Kimbler claimed that he had discovered that one piece exhibited extraterrestrial properties. However, in SUNlite 3-5 (page 4), I pointed out that the values he presented fell within the terrestrial range if one included the margins for error. Since then, he seems to have pulled back on the claim. This did not prevent him from implying to the “Chasing UFOs” team that what he was showing them, was part of the crashed saucer.
While the “Chasing UFOs” team was stumbling around in the dark waving metal detectors over the “crash site”, something strange happened. As the team was sifting an ant hill for possible alien scraps, Erin Ryder got up and decided to go searching for more debris on her own. She surprisingly found something with her metal detector. Some quick digging revealed a silver Air Force button. They would determine this came from the 1947-1949 time frame, implying something significant occurred on the Foster Ranch that summer. Ben McGee’s blog would later reveal that they had shown the button to a historian, who determined it came from a time period after 1949! He would add that this type of button was only found on dress uniforms and not working fatigues, which is what one would expect from a field operation.
I realized that they made these errors when I saw the button. In July of 1947, there was no Air Force and the 509th was part of the Army Air Corps. The Army Air Corps buttons I have seen had either the army eagle or a propeller/star with wings. Of course, one begins to speculate about how the button might have gotten there. Is it pure luck that they found this button in the dirt or was it possible that it was planted by others? If it was a button found by chance, it does not state much. Maybe it was a button from some officer’s uniform that happened to be in the area? The 1997 USAF report documented all sorts of military activities outside the White Sands area in the 1950s. In addition to the activities of the test dummy drops, Holloman also launched many research balloons, which landed all over New Mexico (as well as places outside the United States!). It would not be any surprise that one might find a uniform button some place in the New Mexico desert.
Kevin Randle also commented about this in his blog. Kevin mirrored the comments about the button and that it was only available after September 1947. He also seemed to think the button was very likely planted by somebody because it was too pristine to have been in the dirt for over fifty years. Who would do such a thing? It could have been a Roswell crash proponent but they would have to know where the team would be stumbling around, which points towards the producers of the show. In SUNlite 3-1, Peter Merlin described how a producer had him “plant” a bit of material at a “crash site” and treat it as if it were just found! Did the producers of this program do the same thing?
More whining from the dream team!
Anthony Bragalia added his whining to the mix about skeptical criticism of the “dream team” in the July 15th edition of Saucer Smear. If they don’t want anyone to comment, why do they keep making announcements? He also stated that I declared they would cover-up evidence of a prosaic explanation. I did not actually state that. I posed the question wondering if they would announce such information if they found it. Mr. Bragalia closes by referring to Sheridan Cavitt as a liar and stating that no military personnel interviewed reported they saw a weather balloon at the ranch. The only military personnel, who are known to have gone to the ranch, are Marcel and Cavitt. All other individuals interviewed have never been proven to have actually been at that Foster Ranch in July 1947. We also know that in the 1947 media accounts, Jesse Marcel Sr. and Mac Brazel both described materials from a balloon. Bessie Brazel also stated so in her interviews/affidavit. Finally, the photographs at Fort Worth (the only physical evidence from 1947)show a radar reflector and balloon materials. If Bragalia is going to ignore or not mention this testimony/evidence, when making such proclamations, he demonstrates that my question about some of the team member’s objectivity is a valid one.

Quelle: SUNlite 5/2012

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Peter Merlin comments concerning SUNlite 4-4

Last issue’s Roswell commentaries sparked some interesting comments by Peter Merlin. His statements were worth publishing and commenting upon:
On lightning strikes to aircraft and spacecraft:
In 1976, I was on a flight to New York City in an American Airlines 747. We approached the airport in a thunderstorm during which I witnessed several lightning strikes to the aircraft. I vividly recall a hit to the tail that resulted in a shower of sparks visible through my window, and I saw a bolt strike the outboard right hand engine (or very near to it). In any case, we landed without incident. In later years, when I worked at Burbank Airport, I saw a Convair 440 that sustained lightning damage. The bolt struck the nose area, traveled through the fuselage, and blew off the cap on the vertical tail. Again, a commercial aircraft had survived a significant lightning incident. That said, I have also seen the opposite end of the spectrum. I was at Cape Canaveral in April 1987 when Atlas-Centaur 67 was launched into a thunderstorm. The 11-foot-tall aluminum alloy tube, trailing hot plasma, became an instant lightning rod. It was stuck nine times before it got more than half a mile downrange. Electrical damage to the Centaur Digital Control Unit resulted in an erroneous hardover yaw command and subsequent destruction of the vehicle and payload. Presumably, a civilization with the technology for crossing interstellar space could devise some decent electrical shielding for their spacecraft.
My comment: With the exception of the UNMANNED (and this is important to note) Atlas-Centaur mentioned by Peter, I still find it amazing that our manned aerial craft and spaceships can withstand lightning strikes and are designed to handle them. My point of this section was to demonstrate how our “primitive” technology has considered the possibility of lightning strikes and other adverse conditions to help the craft survive such events. For some reason the aliens were not very bright and designed a craft that could cross the interstellar void but not handle the weather presented by the planet they were exploring.
On private photographic records of government crash retrievals:
In October 1959, the Navy’s YF4H-1 Phantom II prototype crashed on a ranch near Frazier Park, California, during a test flight from Edwards Air Force Base. Military officials instructed the landowner in no uncertain terms not to take any pictures of the crash scene. He ignored this instruction, and managed to take some pictures from a low rise about within a quarter mile of the impact point. When I visited the ranch in June 2007, the original landowner’s son provided one of these photos, which was instrumental in pinpointing the crash site. Fortunately for historians and researchers, the government doesn’t always succeed in preventing civilians from acquiring documentary evidence.
My Comment: The missing photographs of the huge gouge at the Foster Ranch site has always made me skeptical of its existence. If it did last for over a year, it should have been photographed by the locals at some point. Additionally, nobody wrote letters or made diary entries documenting that they had picked up debris and the military had confiscated it
On military intimidation of civilian witnesses:
Following the 1963 crash of an A-12 near Wendover, Utah, officials went to great lengths to prevent disclosure of the top secret aircraft to unauthorized persons. Cleanup was given top priority, and efforts were made to conceal the wreckage before it was removed from the scene. The CIA had the Air Force provide a cover story that an F-105 had crashed. The only serious threat came from reporter Art Kent of KUTV television news in Salt Lake City who claimed to have pictures of the accident scene and planned to show them on the evening news. OXCART project personnel debated how to approach Kent in attempts to suppress the photos. Brig. Gen. Boyd Hubbard made arrangements for an Air Force representative with Office of Special Investigations (OSI) credentials to contact Kent and request that he not air the pictures. Kent, surprisingly with no reluctance, agreed to mail the pictures to Hubbard at Nellis. In September 1967, a top secret D-21B was accidentally launched during a captive test flight from Area 51. After it crashed in a rural area, recovery forces with armed security personnel arrived and closed off the area to local residents. One witness now recalls with bitterness how Air Force personnel ordered him out of the area with a warning to forget what he had seen. But, not everybody was unhappy with the uninvited guests. USAF/CIA liaison Col. Frank Hartley somehow learned that another witness had taken unauthorized photos of the crash scene. Reluctant to strong-arm the civilian, he asked if there was anything he might be able to exchange for the film. The civilian subsequently traded his film for a cream pie. Sometimes it is easier to offer a gift or appeal to someone’s sense of patriotism than to bully them.
My Comment: It seems odd that the military in actual documented cases behaved so differently than the military at Roswell and other UFO crashes. In peacetime, and in the United States, there is absolutely no need for heavy-handed tactics of threatening civilians with their lives and confiscating/damaging property. To do so would be violating several laws and military regulations. Contrary to statements by the authors, such actions would have sparked written letters to various elected officials and the news papers in Roswell (as well as other media outlets). The failure of any such evidence to be produced indicates these events probably never happened this way.

Quelle: SUNlite 5/2012

Balloon material testing - Part II

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Last issue, I discussed my tests with balloon materials and the results I had obtained. For some reason, some Roswell crashologists seemed to have confused what I was trying to prove. I was not trying to replicate the exact conditions of the balloon material from the “cluster of balloons” launched on June 4th. What I was trying to do was to determine whether Professor Moore’s recollections/statements about the balloon material’s reaction to sun light was more accurate than the claims made by Roswell crashologists concerning the balloon materials. My tests demonstrated that some of the claims regarding the balloon materials made by the proponents of an alien spaceship crash were not accurate. Meanwhile, the result did confirm what Professor Moore had stated in various settings over the years after he had performed his own tests.
Recognizing that I probably could not duplicate the conditions in the New Mexico desert and wanting to see if others got the same results, I mailed out some samples to skeptics to see what results they would obtain. Two of the skeptics performed similar tests to mine. The first was Lance Moody, who tested from Mason Ohio. The second was James Carlson, who was located in Albuquerque, New Mexico. Would their results differ significantly from mine?
Lance Moody’s report
Lance sent me an e-mail documenting his results:
Mason, Ohio June 12th-July 12th
I received the neoprene material from Tim Printy by mail. It was packed in a sealed zip lock bag. The material was a light tan in color and very wrinkly. It was thin but quite strong and stretchable but I would guess that it was not as strong a child’s balloon, which is made from a thicker material.
On the morning of 6/12/12, I took the long piece of the neoprene and folded it over itself to create an upper layer exposed directly to the sun and a lower layer beneath it. I pinned the material to a piece of wood and placed it in a position to receive as much sun as possible. It was a very sunny day.
Within the first hour, there was a change in the color of the upper layer of material. It had become slightly darker. After 8 hours, the color was very much darker on the upper layer. The lower layer was only slightly darker than its original color. There was no noticeable change in the texture/elasticity of the material. (see image below)

Over the next days and weeks, I noted that the color of the outer layer did get slightly darker but there nowhere near as dramatic a change as on that first day. Much of the color change takes place in those first hours. The texture did change a bit each day.

After 9 days, the material of the upper layer is drier looking. It’s strength against tearing is reduced but it is still relatively strong and stretchable. The lower layer is much closer to the same texture as day one. It’s color is much lighter than the upper layer.
After 16 days, the upper layer is noticeably more fragile. It is easy to tear, almost as weak as tissue paper. The lower layer is still stretchy and still lighter in color than the upper layer.

After 25 days (see image on left for material after 21 days), there is even more deterioration in the upper layer. It makes a crinkly sound when handled. The lower layer is weakened but still retains some stretchiness. It’s color is still lighter than the layer above. If I take a piece of the upper layer and ball it up in my hand, it produces very tiny flecks of material.
During the course of the test, the wind occasionally blew enough to displace the pins. I would re-pin the material when I discovered this but I have no idea how much additional sun my lower layer got during these periods. Certainly it got darker than it would have otherwise.
We had very little rain to speak of and much sun, including several record setting high temperatures. One night a very powerful thunderstorm moved through and I brought the whole operation inside.
I note no odor from the neoprene to speak of. If you put your nose right up on it, there is a slight burnt rubber smell. On most days, I took at least one photo of the test.
I am struck, after handling the material so closely, as to how similar it appears to what we see in the famous Ft. Worth/Roswell photos. I see in the photos what appears to be the same variety of textures as I obtained in this test: crinkly and torn portions and stretchy lighter portions of neoprene.


The image to the right was taken by Lance on day 16 demonstrating the elasticity of the material at that point. This was consistent with what I had observed in my testing.
Lance had felt that our tests would come under criticism because they were not conducted in New Mexico under similar conditions that the NYU balloons had experienced. I was not too concerned about such criticism because Professor Moore had already tested materials under those conditions and described the results he had obtained. However, Lance convinced me that it wasn’t a bad idea. So, I contacted James Carlson, who was quick to volunteer his services.

James Carlson report (based on e-mail reports from James)
James began his testing on June 10th at 1330 local time. By 1830, the balloon had changed color to a dark gray the same way the tests by Moody and myself had (see image to the right). James reported the following about the texture:
As for texture, it really hasn’t changed that much. There is no brittleness at all, and if I had to find some change, all I would suggest (and I probably wouldn’t swear to it, since it’s significantly warmer from the sunlight) would be a possible weakening; it seems a little thinner, but only a very little. It still stretches with the same consistency, at least in my judgment.
He would add this comment the following day:

As for texture of the material, the “weakness” I noted earlier must have been caused by direct heat. I know it’s expected of other materials due to the increased molecular vibrations, but I didn’t expect the balloon bits to snap back once they had cooled. The rubber (or whatever it is) suffered no permanent changes. It seems just as consistent as it was before the tests.
James’ testing continued and the material darkened at a similar rate to the other tests. By the 13th, James reported that the texture had weakened. This was not unexpected as my tests showed that after three days, the texture of the material had begun to change on top. By the 17th, the balloon material on some parts of the balloon had turned black (see image on the right) On the 18th of June, he had a windy day and discovered the material had been blown such the unexposed portions became exposed to the sun. As a result the underlying layer became darker although it still had a tannish color to them. On the 20th, James reported that the texture, while having changed somewhat, still did not exhibit brittleness or tearing.

On the 22nd (12 days after putting the material out), James noticed that the material was splitting in the top layer (see image to the bottom left). My test showed splitting on the 13th day but I had some rain for several days early in my testing. Lance noticed the splitting around day 16. So, once again, it appeared that the tests agreed within a certain margin of error.
On June 26th (16 days into the test), James reported:

As for today, the samples are definitely drier, with the only exception being the few square inches that still retain some of the original coloring. Of the two shades of black that you can make out, the lighter is the driest, and it’s starting to reflect some of the “brittleness” you’ve mentioned in the past. It’s much less malleable, but it still retains enough body to put off any type of “flaking”. It’s much easier to tear through, and you’ll note that there are more “splits” in the samples......
This can be seen in the image to the left, which was taken on June 27th.

On the 28th (day 18), James had bad news to report:
As you can see in the attached photos, the entire lower sample was pulled free of the staples last night and was then blown hither and yon, yon being where I was able to find one small part of the whole (about 15 feet away) and hither being God knows where (I couldn’t find it).
While the gusting winds are typical of the New Mexican desert, one has to remember this was a test strip of material on a board that was exposed to the sun in a position well above the ground. It is not quite the same as a balloon fragment lying flat on the dirt. If the wind did play a role it might have broken the balloon materials into smaller fragments and littered them over a large area (as well as blowing the ML-307 fragments “hither and yon”). This seems to be what Bessie and Mack Brazel described.

On the 29th (day 19), James started to notice a slight brittleness in the remaining material. On July 5th (day 25), James noted there were still portions of his sample that displayed some of the original color of the balloon strip. Sometime between July 6 and 7 (day 26-7), the balloon material was once again blown off the board. James, once again, retrieved the fragments. Despite all of this time in the sun and the fragmentation of the pieces, he still had sections that retained some of their original color. By day 30 of his testing, the remaining fragments had become a dark black parchment-like material. He sent me these scraps for examination.
The thing I noticed concerning the samples I received was that there were certain sections of the dark material that retained its elasticity. One part, I could put my finger into and stretch. However, another section tore quite easily. When I put the material up to the sunlight, I noticed that there were two different densities and colors visible (see image lower left). This is all consistent with what both Lance and I experienced in our tests.

Conclusions
There really is not much to conclude other than what I wrote in the last issue of SUNlite appears to be confirmed. There is no indication that after a few weeks the material turns to ash as some have claimed. There is also no indication that one can put a balloon out for a few hours and achieve the results one sees in the Fort Worth images. However, there is plenty of indication that what professor Moore had written was accurate and that the material in the Fort Worth images contain balloon material that was exposed to the sun for a considerable amount of time ranging from about ten days to over a month.
I tried to present most of the data for all to see but there is only so much space for the images. Professor Moore did conduct these kinds of tests but just made general statements about his results. On the following page, there is a collection of photographs converted to black and white (without any other adjustment) for comparison to the Fort Worth image. At this point, it will take something a lot more convincing than a change of color to convince me that the balloon materials in the Fort Worth images came from something that was put out in the Texas sun for a few hours as a trick to fool the media and public.
June 27th 1730
July 1st 1200
July 7th 1200 (note bits of tan color on largest piece)

Photographs of the two tests (duration and daily test) conducted in Ohio, NH, and NM (with an additional daily test in Florida) compared to the balloon debris in the Roswell photographs. Images were converted to black and white for comparison without any other adjustment. The balloon material tested for 30 days appear to be a closer match to the Fort Worth photographs in both color and appearance. In none of the duration tests, did the balloon materials turn to ash although sections of the balloon turned brittle and began to fragment. One can infer that this effect is usually experienced after many more weeks just as Professor Moore would state after he had conducted his own tests. Meanwhile, the texture of the balloon material after one day showed no significant change.

Quelle: SUNlite 5/2012


Tags: UFO-Forschung 

2285 Views

Sonntag, 8. Juni 2014 - 10:10 Uhr

Astronomie - Saturn im Focus von Cassini-Huygens

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Me and My Shadow

Saturn's rings cast shadows on the planet, but the shadows appear to be inside out! The edge of Saturn's outermost A ring can be seen at the top left corner of the image.  Moving towards the bottom of the page, one can see the faint Cassini Division, the opaque B ring and the innermost C ring, which contains several ringlets that appear dark against Saturn in this geometry.  The bottom half of the image features the shadows of these rings in reverse order superposed against the disk of the planet: the C ring, the B ring, the Cassini Division and the inner half of the A ring.

This view looks toward the unilluminated side of the rings from about 28 degrees below the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on Dec. 2, 2013, using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 752 nanometers.

The view was acquired at a distance of approximately 750,000 miles (1.2 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 57 degrees. Image scale is 45 miles (72 kilometers) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

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Titan's Crescents

Titan's south polar vortex mimics the moon itself, creating an elegant crescent within a crescent. Situated above the surrounding polar atmosphere, the raised walls along the sunward side of the vortex just catch the grazing sunlight, creating a crescent of its own.Titan (3,200 miles, or 5,150 kilometers across) is Saturn's largest moon and possesses a dense and dynamic atmosphere. For a color image of the south polar vortex on Titan, see PIA14919.  For a movie of the vortex, see PIA14920.

This view looks toward the trailing hemisphere of Titan. North on Titan is up. The image was taken with the Cassini spacecraft wide-angle camera on Dec. 1, 2013 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 939 nanometers.

The view was obtained at a distance of approximately 108,000 miles (174,000 kilometers) from Titan. Image scale is 6 miles (10 kilometers) per pixel.

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Still Alive

The spokes in Saturn's rings continue to be active and Cassini scientists continue to study them in order to unravel their mysteries. The spokes, visible near the center of the image, appear bright against the dense core of the B ring, which is the darkest section of the rings shown here in silhouette. Conditions favorable to the production of spokes are expected to wane as Saturn approaches its northern summer solstice. Scientists are eager to monitor the transition, the timing of which could yield valuable insight into the mechanisms that form these intriguing and ethereal features.

This view looks toward the unilluminated side of the rings from about 47 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Oct. 19, 2013.

The view was acquired at a distance of approximately 1.2 million miles (1.9 million kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 122 degrees. Image scale is 72 miles (115 kilometers) per pixel.

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Tethys' Terrains

Tethys' trailing side shows two terrains that tell a story of a rough past. To the north (up, in the image) is older, rougher terrain, while to the south is new material dubbed "smooth plains" by scientists.

The smooth plains are roughly antipodal to the large impact crater Odysseus. Odysseus, which is on the far side of Tethys (660 miles, or 1,060 kilometers across) from this perspective, is out of view. (See PIA12588 for a view of Odysseus.) It's thought that the impact that created Odysseus also created the smooth plains, although exactly how this happened is not yet clear.

This view looks toward the trailing hemisphere of Tethys. North on Tethys is up and rotated 2 degrees to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Nov. 27, 2013.

The view was obtained at a distance of approximately 1.1 million miles (1.8 million kilometers) from Tethys. Image scale is 7 miles (11 kilometers) per pixel.

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High Vortex

Titan's polar vortex stands illuminated where all else is in shadow. Scientists deduce that the vortex must extend higher into Titan's atmosphere than the surrounding clouds because it is still lit in images like this. Although the south polar region is now in winter, the Sun can still reach high features like the vortex.

Titan (3,200 miles, or 5,150 kilometers across) is Saturn's largest moon. For a color image of the south polar vortex on Titan, see PIA14919.  For a movie of the vortex, see PIA14920.

This view looks toward the Saturn-facing hemisphere of Titan. North on Titan is up and rotated 32 degrees to the right. The image was taken with the Cassini spacecraft wide-angle camera on Feb. 3, 2014 using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 742 nanometers.

The view was obtained at a distance of approximately 134,000 miles (215,000 kilometers) from Titan. Image scale is 8 miles (13 kilometers) per pixel.

Quelle: NASA


2329 Views

Sonntag, 8. Juni 2014 - 09:59 Uhr

Raumfahrt - "Hallo, Welt!" NASA beamt Video von Space Station per Laser

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This artist's concept shows how the Optical Payload for Lasercomm Science (OPALS) laser beams data to Earth from the International Space Station.

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"Hello, World!" came the message from the International Space Station as NASA successfully beamed high-definition video via laser from space to ground on Thursday, June 5. The 175-megabit video transmission was the first of its kind for the Optical Payload for Lasercomm Science (OPALS) with the goal of improving the way we receive data from orbit and beyond. In fact, this emerging technology of optical communications—or lasercomm—is likened to an upgrade from dial-up to DSL.

"It's incredible to see this magnificent beam of light arriving from our tiny payload on the space station," said Matt Abrahamson, OPALS mission manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California.

OPALS launched to the space station aboard the SpaceX Dragon earlier this spring. This technology demonstration furthers NASA's exploration of higher-bandwidth methods of communicating with future spacecraft. Optical communications tools like OPALS use focused laser energy to achieve data rates 10 to 1,000 times higher than current space communications, which rely on radio portions of the electromagnetic spectrum.

OPALS' success also is an important step in improving communication rates with spacecraft beyond low-Earth orbit. The instrument allows for communications rates to keep pace with the ever-increasing data generation produced by scientific instruments. The capability could replace the Federally-regulated radio frequencies currently in use from orbit to meet the needs anticipated by researchers for future missions, like Mars.

"We look forward to experimenting with OPALS over the coming months in hopes that our findings will lead to optical communications capabilities for future deep space exploration missions," Abrahamson said.

The space station moves through Earth's sky at approximately 17,500 mph. This speed requires extreme precise pointing ability. It's equivalent to a person aiming a laser pointer at the end of a human hair 30 feet away and keeping it there while walking. To achieve this precision, OPALS locked onto a ground beacon emitted by the Optical Communications Telescope Laboratory ground station at the Table Mountain Observatory in Wrightwood, California.

Once locked onto the signal, OPALS began to modulate the beam from its 2.5-Watt 1,550-nanometer laser to transmit the video. The entire transmission lasted 148 seconds and achieved a maximum data rate of 50 megabits per second. It took OPALS 3.5 seconds to transmit a single copy of the “Hello World!” video message, which would have taken more than 10 minutes using traditional downlink methods. The message was sent multiple times during the transmission.

The OPALS instrument was built at JPL as part of the Phaeton hands-on training program and is slated to run for a prime mission of 90 days. The OPALS Project Office is based at JPL, a division of the California Institute of Technology in Pasadena. During these transmissions, NASA also will train personnel in optical communication systems operations, leading to improved optical communication instrument design.

Commercial ventures can likewise take note of the project, as it proves the use of lasercomm for optimized communications from space. This may mean higher definition video feeds from near-Earth assets, such as satellites, as well as those in deep space, like future Mars rovers. This improves the interaction and experience with the stakeholders, whether they be researchers, engineers or consumers. And if you remember the days of having to leave the room to download a video when using DSL, you know that higher-speed downloads are definitely the way to go!

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Quelle: NASA


2440 Views

Samstag, 7. Juni 2014 - 23:00 Uhr

Raumfahrt - ESA entwickelt ein Docking-Ring zum Einsatz für alle Raumschiffe

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Connecting spacecraft in orbit will never be simple, but ESA is taking the next step to allow the next generation of vehicles of all types from around the world to link up with each other.

The International Space Station has two sets of incompatible docking ports, one designed for Russian spacecraft and Europe’s space freighter, and another design for the now-retired US Space Shuttle. There also are berthing ports for vessels that cannot dock on their own but are first captured by the Station’s robotic arm.

Adding to the complexity, Russian docking ports have a male and female version, like an electrical plug and socket. This means that a spacecraft can only dock with a vehicle that has the correct receiving port.

The Station’s docking mechanisms are designed to handle large, 100-tonne craft such as the Shuttle. They grasp a spacecraft as it pushes into the Space Station – like a train coach connecting to its locomotive.

This approach works fine for heavier vehicles but the next generation is gearing up to be smaller and up to 10 times lighter. A 10-tonne vessel would simply bounce of these ports because it does not have enough momentum to engage the locking rings.

ESA’s International Berthing and Docking Mechanism embodies the international standard that will work with a lighter generation of space vehicles. It is identical for both craft – any two vehicles can dock or be berthed.

Although the connection is defined by the international standard, the mechanism behind the docking ring can be designed in any way, making further cooperation in space easier.

The International Berthing Docking Mechanism is the only design that senses the forces at play between two spacecraft and adapts accordingly, ‘grabbing’ a lighter vessel or absorbing the loads of a heavier vehicle.

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Soft space docking

To overcome these limitations, a new international standard will work with a lighter generation of space vehicles and is identical for both craft – any two vehicles can dock or be berthed.

Although the connection is defined by the international standard, the mechanism behind the docking ring can be designed in any way – making further cooperation in space easier.

ESA’s own International Berthing Docking Mechanism is the only design that will sense the forces at play between two spacecraft and adapt accordingly, ‘grabbing’ a lighter vessel or absorbing the loads of a heavier vehicle.

The first engineering model is being built by QinetiQ Space in Belgium to test the mechanisms on Earth, with a goal of having the system available for flight by 2017.

The Sierra Nevada Corporation in the US is already investigating collaboration with ESA for its first use on Dream Chaser, a reusable spaceplane that will carry astronauts and cargo to low orbit and land like an aircraft on a runway.

Quelle: ESA


2402 Views

Samstag, 7. Juni 2014 - 16:45 Uhr

Astronomie - Laser zünden 'Supernova' im Labor

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Laser beams illuminate a small carbon rod and launch an asymmetric shock inside a chamber filled with argon gas. The shock and the turbulent flow are captured with the Schlieren imaging technique (blue-black hues). The electron density predicted by computer simulations (blue-red hues) is superimposed. (Courtesy: Oxford University/University of Chicago)

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One of the world's most powerful laser facilities has been used to create tiny versions of supernova explosions in the laboratory. The goal of the research, which has been done by an international team of physicists, is to gain insight into one of the most energetic and unpredictable events in the universe. The researchers also hope that their experiments could lead to a better understanding of the role played by cosmic turbulence in creating the powerful magnetic fields seen in some atypical supernova remnants, such as Cassiopeia A.

Supernovae are massive stellar explosions that are triggered either when the fuel within a star reignites or its core collapses under extreme gravitational forces. The explosion expels most of the star's material, which in turn sends out a shock wave that acrosses long distances in interstellar space. The shock wave binds most of the ejected stellar material and other dust in its path, creating what is known as a supernova remnant (SNR). While most SNRs have regular, shell-like features, some, such as Cassiopeia A, have irregular and unexplained shapes. The Cassiopeia SNR is about 11,000 light-years from Earth and light from it first reached our planet 300 years ago. Optical images of the explosion reveal irregular "knotty" features, while X-ray and radio observations show the presence of magnetic fields about 100 times stronger than those in the surrounding interstellar medium.

Knotted shock

It is these oddities of Cassiopeia A that caught the attention of plasma physicist Gianluca Gregori of Oxford University and his team of international researchers. Gregori told physicsworld.com that the initial idea for the study came from conversations with astronomers about the problems in understanding the formation of magnetic fields in the universe. "Over a coffee break, we started realizing that perhaps we should try to perform a lab experiment to see if what we think is happening is really happening," he says.

While the origin of the large magnetic field in the interior of Cassiopeia A is still unknown, one possibility is that the shock wave could have passed through a region of space that is filled with dense clumps or clouds of gas. "In Cassiopeia A, the probable explanation that we proposed is that the irregular feature is caused by the supernova shock being perturbed and fragmented by dense clouds that surrounds the star," says Gregori.

It may sound surprising that a table-top laboratory experiment that fits inside an average room can be used to study astrophysical objects that are light years across
Gianluca Gregori, Oxford University

To test this idea, Gregori and colleagues decided to recreate a slightly smaller "bang", devising a laboratory-based method to investigate this turbulence. "It may sound surprising that a table-top laboratory experiment that fits inside an average room can be used to study astrophysical objects that are light-years across," says Gregori. The researchers used the Vulcan laser facility at the Rutherford Appleton Laboratory to recreate their SNRs. "Our team began by focusing three laser beams onto a carbon-rod target, not much thicker than a strand of hair, in a low-density gas-filled chamber," says Jena Meinecke, an Oxford University graduate student who headed the experiment. When the rod is heated to a temperature of a few million degrees kelvin, it explodes. This creates an asymmetric shock wave that expands outwards through the argon gas, much like a real supernova in space.

Turbulent flows

In the experiments, the dense gas clumps or clouds that would surround an exploding star were simulated by placing a plastic grid 1 cm from the target. This disturbs the shock front and results in turbulent flow. The shock and the turbulent flow is captured a 300 billionth of a second after the laser shot, using a special imaging technique.

Gregori mentions that the team was lucky in that its meticulously planned experiment worked perfectly in the time available at the Vulcan facility. "Sometimes, even when you prepare for months, you encounter problems. This time all the diagnostics and the team were fantastic," he exudes, pointing out that access to the laser is fairly competitive.

The researchers found that as the shock wave moved through the grid, turbulence and irregular features began to appear. "We found that the magnetic field is higher with the grid than without it," says Gregori, explaining that the result "is consistent with both observations and numerical models of a shock wave passing through a 'clumpy' medium". As higher magnetic fields imply a more efficient generation of radio and X-ray photons, the team's results call into question the currently accepted idea that supernova explosions expand into uniformly distributed interstellar material.

Gregori points out that the research has an impact on more than just SNRs, because the amplification of magnetic field via turbulence applies to many astrophysical systems. "We know that there are magnetic fields, but we don't know how they got there in the first place. The standard mechanism that is usually invoked is that tiny 'seed' fields were produced just after the Big Bang and then those fields were amplified by turbulence."

Quelle: physicsworld


2505 Views

Samstag, 7. Juni 2014 - 16:30 Uhr

UFO-Forschung - Wurde Apollo-7 von grünem Feuerball verfolgt?

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Anthony Bragalia, as is his custom, wrote another sensationalist style piece on his blog, which discussed the green fireball phenomenon. Some of the evidence he presented had little to do with the green fireball observations of the late 1940s other than somebody recorded green lights in the sky. However, there were two claims that Mr. Bragalia listed that intrigued me:
- Revealed here are remarkable images (recently found buried within NASA space footage archives) of a Green Fireball that seems to “follow” our astronauts
- Striking and exceeding rare film has been located, also taken from space, where one can vividly see the strange Green Fireballs doing the impossible: exiting the earth’s atmosphere rather than entering it
All of these comments had to do with Bragalia “finding” two images that showed what appeared to be green fireballs moving across the frame. One appeared to be even exiting the earth’s atmosphere! Bragalia would imply that these “green fireballs” actually exited the earth’s atmosphere to follow/track out astronauts.
Dispelling some myths about meteors
In his article, Mr. Bragalia stated that it was “impossible” for meteors to exit the earth’s atmosphere. However, this is not true. Meteors can, and do, leave the earth’s atmosphere. They often are referred to as “earth grazers”. It is all a matter of what angle the meteoroid enters the earth’s atmosphere. If it has a low entry angle, it will basically “skip” off the earth’s atmosphere. A great example is the daylight fireball of August 10, 1972. It reached a low point of below 60 km and then began to increase in altitude as it exited the earth’s atmosphere. When I pointed this out to Mr. Bragalia, he stated that he did consider this possibility (yet declared it “impossible”) and felt the angle in the photographs was too steep (yet he provided no analysis to demonstrate this). He added that meteors don’t follow astronauts even though there is little evidence to indicate these “green fireballs” were actually doing this.
Another statement about “green fireballs” that Anthony Bragalia noted was that nobody was ever able to recover any fragments from these “green fireballs” and they leave no impact marks. I beg to differ because the Peekskill fireball was “green” and fragments were recovered. The truth is meteorites are not always produced by fireballs. I have seen plenty of searches for meteorites following a bright fireball over the years come up empty. Additionally, meteorites rarely leave any “impact marks” in the ground. It takes a really large meteor to create a crater in the ground. On October 7, 2008 an asteroid (2008 TC3) about 7-16 feet in size entered the earth’s atmosphere. A search for the debris revealed plenty of meteorites but they were simply laying around on the desert. They left no obvious impact marks.


The Apollo 7 fireballs
Mr. Bragalia’s evidence for “green fireballs” following Apollo 7, were two photographs from the NASA archive (AS07-5-1613 and AS07-6-1700). However, these images were not “recent revelations” as we are led to believe. The Above Top Secret Forum had discussed these two images back in 2008 and it was announced on a lunar enigmas web site around the same time.
Curious, I decided to check the archives for the source images. They did show the objects in question but something caught my eye. In relation to the borders of the frame, both images showed the “fireball” going in the same direction!. I found that a bit peculiar and I began to suspect that this may not be an actual photograph of a meteor but something that was part of the film or scanning process. If so, I should find more of these artifacts in other images. So, I decided to “scour the deep recesses of the NASA archive” for anymore “buried” images as well. It did not take too much “scouring” to find two more examples of the “green fireballs”. The two images were AS07-8-1923 and AS07-8-1925. Both showed the green fireballs and they were also going in the same direction in relation to the film edges. Even more astounding was that AS07-8-1925 had recorded two on the same frame! If these were random fireballs, or even alien spaceships, the chances they would all move in the same direction, in relation to the film frame, seems to be extremely unlikely. After finding these two additional images, I stopped my search. I would not be surprised if I looked through all the images, I could find more of these green fireballs and most, if not all, would go in the same direction.
It is my belief that the images actually show some artifact in the original Kodachrome emulsion that was caused by the advancement of the film or by handling over the years. It also may have been produced in the scanning process (either by the scanner, damaged emulsion, or from prints that were scanned). This seemed more likely than green fireballs that always went in the same direction as the film.

Walt Cunningham speaks
When I shared my findings with James Oberg and other skeptics, James responded that he would contact Walt Cunningham, who was one of the crew of Apollo 7. When shown the story by Bragalia, he responded in July 22nd e-mail to James Oberg:
Rubbish, of course. I have my collection of prints from back in 1968. As you know, I took a majority of our pictures, and these two are both pics of the Middle East - - - and we weren’t being followed.
Cunningham would later state that he looked at his prints and did not see these “green fireballs” that are in the scans being used by Bragalia and others. That indicates that whatever these anomalies were, they were not originally recorded on the film and appeared much later.
Conclusion
The images being used to promote this case have artifacts in them that are apparently from the film or scanning process that look like fireballs. There is no reason to believe they are actual meteors or spaceships. Therefore, the case of the Green Fireballs chasing the Apollo 7 capsule can be considered esssentially closed unless somebody can prove they are spaceships/meteors.

Quelle: SUNlite 4/2012


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