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Sonntag, 30. August 2015 - 14:44 Uhr

Astronomie - Fetter Bolide über Andalusien am 28.August 2015

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Foto:Dr. Josep M. Trigo

 

Tags: Astronomie 

1579 Views

Sonntag, 30. August 2015 - 11:00 Uhr

Astronomie - Vollmond-Spechteln

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"Glockenhell" sagt man hier, war der Vollmond in der heutigen Nacht von Samstag/Sonntag und lud zum Spechteln ein:

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Fotos: ©-hjkc


Tags: Astronomie 

1819 Views

Sonntag, 30. August 2015 - 09:53 Uhr

Astronomie - Herkunft von Saturns F-Ring und seinen Hirten Satelliten aufgedeckt

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HYODO Ryuki, a second-year student in the Doctoral Program, and Professor OHTSUKI Keiji of the Graduate School of Science at Kobe University have revealed that Saturn’s F ring and its shepherd satellites are natural outcome of the final stage of formation of Saturn’s satellite system. Their finding has been published online in Nature Geoscience on August 17.
Saturn, which is the second largest planet in our solar system, is known to have multiple rings and satellites. In 1979, Pioneer 11 discovered the F ring located just outside the main ring system that extends tens of thousands of kilometers. The F ring is very narrow with a width of only a few hundred kilometers, and has two shepherd satellites called Prometheus and Pandora, which orbit inside and outside the ring, respectively. Although the Voyager and Cassini spacecraft later made detailed observations of the F ring and its shepherd satellites, their origin has not been clarified.
According to the latest satellite formation theory, Saturn used to have ancient rings containing many more particles than they do today, and satellites formed from spreading and accretion of these particles. During the final stage of satellite formation, multiple small satellites tend to form near the outer edge of the ring. On the other hand, observations by Cassini indicate that the small satellites orbiting near the outer edge of the main ring system have a dense core. In their simulations using in part computer systems at the National Astronomical Observatory of Japan, HYODO and OHTSUKI revealed that the F ring and its shepherd satellites formed as these small satellites with a dense core collided and partially disintegrated. In other words, the system of the F ring and its shepherd satellites is a natural outcome of the formation process of Saturn’s ring-satellite system.
This new finding is expected to help elucidate the formation of satellite systems both within and outside our solar system. For example, the above formation mechanism can also be applied to the rings and shepherd satellites of Uranus, which are similar to those of Saturn.
HYODO, now visiting Institut de Physique du Globe de Paris for his research from this spring (April 2015) remarked, “Through this study, we were able to show that the current rings of Saturn reflect the formation and evolution processes of the planet’s satellite system.”
“As plans are underway in and outside of Japan to explore the satellite system of Jupiter and the satellites of Mars,” said OHTSUKI, “we will continue to unravel the origin of satellite systems, which is key to understanding the formation process of planetary systems.”
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Figure 1: Images of Saturn’s Main Rings, the F Ring, and its Shepherd Satellites Obtained by Cassini 
(Left) Saturn’s main rings (NASA/PIA06077).
(Center) The narrow F ring located just outside of the outer edge of the main rings. Two satellites sandwiching the F ring slightly above and to the left of the center of the image are the shepherd satellites Prometheus (inner orbit) and Pandora (outer orbit) (NASA/PIA12717).
(Right) Closer image of the F ring and its shepherd satellites Prometheus (inner orbit) and Pandora (outer orbit) (NASA/PIA07712). In the center and right images, Saturn is beyond the images towards the right.
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Figure 2: Schematic Illustration of the Latest Satellite Formation Model 
Side view of Saturn’s ring-satellite system.
(Top) Saturn’s rings used to be more massive than they are today, and they spread outwards due to collisions and gravitational interactions between particles. 
(Bottom) When particles move sufficiently outward, they merge into satellites due to mutual gravity. These satellites then move farther away from Saturn. Consequently, the satellites that formed earlier when the rings were more massive are larger and located farther out, whereas multiple small satellites tend to form just outside of the main rings at the final stage of the satellite system formation.
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Figure 3: Simulation of a Collision between Two Satellites (Present Study) 
In this simulation, two satellites with dense cores collide at the current location of the F ring. The collision does not destroy the cores, which become two shepherd satellites, and the dispersed particles distributed in between the two satellites form the F ring (The original version of this figure is from the paper published in Nature Geoscience).
Quelle: Kobe University

Tags: Astronomie 

1604 Views

Sonntag, 30. August 2015 - 09:43 Uhr

Astronomie - Staub verdeckt aktive Galaxien beim Wachsen

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A group of researchers from Ehime University, Princeton University, and the National Astronomical Observatory of Japan (NAOJ) among others has performed an extensive search for Dust Obscured Galaxies (DOGs) using data obtained from the Subaru Strategic Program with Hyper Suprime-Cam (HSC). HSC is a new wide-field camera mounted at the prime focus of the Subaru Telescope and is an ideal instrument for searching for this rare and important class of galaxy. The research group discovered 48 DOGs, and has measured how common they are. Since DOGs are thought to harbor a rapidly growing black hole in their centers, these results give us clues for understanding the evolution of galaxies and supermassive black holes.
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Figure 1: Images of 3 DOG's. The left, middle, and right panels show optical image from HSC, near-infrared image from VIKING, and mid-infrared image from WISE, respectively. The image size is 20 square arcsecond (1 arcsecond is 1/3600 degree). It is clear that DOGs are faint in the optical, but are extremely bright in the infrared. (Credit: Ehime University/NAOJ/NASA/ESO)
Co-Evolution of Galaxies and Supermassive Black Holes
How did galaxies form and evolve during the 13.8-billion-year history of the universe? This question has been the subject of intense observational and theoretical investigation. Recent studies have revealed that almost all massive galaxies harbor a supermassive black hole whose mass reaches up to a hundred thousand or even a billion times the mass of the sun, and their masses are tightly correlated with those of their host galaxies. This correlation suggests that supermassive black holes and their host galaxies have evolved together, closely interacting as they grow.
Dust Obscured Galaxies
The group of researchers, lead by Dr. Yoshiki Toba (Ehime University), focused on the Dust Obscured Galaxies (DOGs) as a key population to tackle the mystery of the co-evolution of galaxies and black holes. DOGs are very faint in visible light, because of the large quantity of obscuring dust, but are bright in the infrared. The brightest infrared DOGs in particular are expected to harbor the most actively growing black hole. In addition, most DOGs are seen in the epoch when the star formation activity of galaxies reached its peak, 8-10 billion years ago. Thus both DOGs and their black holes are rapidly growing, at an early phase of their co-evolution. However, since DOGs are rare and are hidden behind significant amount of dust, previous visible light surveys have found very few such objects.
A Search for Dust Obscured Galaxies with HSC
Hyper Suprime-Cam (HSC) is a new instrument installed on the 8.2 meter Subaru Telescope in 2012. It is a wide-field camera with a field of view nine times the size of the full moon. An ambitious legacy survey with HSC started in March 2014 as a "Subaru strategic program (Note 1)"; total of 300 nights have been allocated for a five year period. The Subaru strategic program with HSC started to deliver large quantities of excellent imaging data.
The research team selected DOGs from early data from the HSC Subaru Strategic Program (SSP). DOGs are thousand times brighter in the infrared than the optical and the team selected their targets using the HSC and NASA's Wide-field Infrared Survey Explorer (WISE: Note 2). They also utilized the data from the VISTA Kilo-degree Infrared Galaxy survey (VIKING: Note 3). The all-sky survey data with WISE are crucial to discover spatially rare DOG while the VIKING data are useful to identify the DOGs more precisely.
Consequently, 48 DOGs were discovered. Each of these is 10 trillion times more luminous in the infrared than the sun. The number density of these luminous DOGs is about 300 per cubic gigaparsecs. It is theoretically predicted that these DOGs harbor an actively evolving supermassive black hole. This result provides researchers new insights into the mysteries of the co-evolution of galaxies and supermassive black holes from the unique observational prospects.
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Figure 2: The number density of DOGs that were newly selected in this study, as a function of infrared luminosity. Data represented by the red star is the HSC result. The research team found that (i) their infrared luminosity exceeds 10 trillion suns, and (ii) their number density is about 300 per cubic gigaparsecs (1 gigaparsec is about 3×1025 meter). (Credit: Ehime University/NAOJ/NASA/ESO)
Summary and Future Prospects
In this research, the research team discovered 48 Dust Obscured Galaxies and revealed their statistical properties of infrared luminous DOGs in particular, for the first time.
The first author of the paper Dr. Yoshiki Toba said, "There are no instruments on large telescopes with the sensitivity and field of view of HSC, and hence HSC is unique in its ability to search for DOGs. The HSC survey will cover more than 100 times as much area of the sky as the area used for this study when it is complete, allowing the identification of thousands of DOGs in the near future. We are planning to investigate the detailed properties of DOGs and their central black holes using observations from many telescope."
Also, Professor Tohru Nagao, second author of the paper, said "The Subaru Strategic Program with HSC has just begun. In the near future, exciting results will be released not only from studies on galaxy evolution, but also from in fields such as solar systems, stars, nearby galaxies, and cosmology."
This research will be published on October 25, 2015 in the Publications of the Astronomical Society of Japan (PASJ) Subaru special issue (Toba et al. 2015, "Hyper-luminous Dust Obscured Galaxies discovered by the Hyper Suprime-Cam on Subaru and WISE", PASJ, Vol. 67, Issue. 5 ). Online version was posted on July 12, 2015. This work was supported from the Japan Society for the Promotion of Science (grant No. 25707010) and from the Yamada Science Foundation.
Notes:
In the Subaru Strategic Program, 300 nights have been allocated for five years in total. The superb resolution and sensitivity of these images enable us to find these rare and faint galaxies, to understand the growth and evolution of galaxies and black holes.
The Wide-field Infrared Survey Explorer (WISE) was launched by the National Aeronautics and Space Administration (NASA) in 2009. WISE performed an all-sky survey with high sensitivity in four bands (3.4, 4.6, 12, and 22 microns). WISE has observed over seven hundred million infrared sources so far.
The VISTA Kilo-degree Infrared Galaxy survey (VIKING) is performing a wide area near-infrared imaging survey with five broadband filters using the VISTA InfraRed Camera (VIRCAM) on the VISTA telescope operated by the European Southern Observatory (ESO).
Quelle: Subaru Telescope

Tags: Astronomie 

1649 Views

Samstag, 29. August 2015 - 21:26 Uhr

Astronomie - Wissenschaftler haben Spuren von Kohlenstoff in vulkanischen Glas von den Apollo-Mond-Missionen gefunden

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Evidence of lunar fire fountains
Fire fountains — dramatic, explosive volcanic eruptions — require volatile elements mixed in with lava. New research by Alberto Saal and colleagues suggests that carbon monoxide was the volcanic gas that drove lunar fire fountains.
Photo: Mike Cohea/Brown University
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Research may solve lunar fire fountain mystery
Scientists have found traces of carbon in volcanic glass collected from the Apollo missions to the Moon. The finding may not only explain the driving force behind ancient “fire fountain” eruptions on the Moon but also suggest that some volatile elements on the Moon and Earth have a common origin.
PROVIDENCE, R.I. [Brown University] — Tiny beads of volcanic glass found on the lunar surface during the Apollo missions are a sign that fire fountain eruptions took place on the Moon’s surface. Now, scientists from Brown University and the Carnegie Institution for Science have identified the volatile gas that drove those eruptions.
Fire fountains, a type of eruption that occurs frequently in Hawaii, require the presence of volatiles mixed in with the erupting lava. Volatile compounds turn into gas as the lavas rise from the depths. That expansion of that gas causes lava to blast into the air once it reaches the surface, a bit like taking the lid off a shaken bottle of soda.
“The question for many years was what gas produced these sorts of eruptions on the Moon,” said Alberto Saal, associate professor of earth, environmental, and planetary sciences at Brown and corresponding author of the new research. “The gas is gone, so it hasn’t been easy to figure out.”
The research, published in Nature Geoscience, suggests that lava associated with lunar fire fountains contained significant amounts of carbon. As it rose from the lunar depths, that carbon combined with oxygen to make substantial amounts carbon monoxide (CO) gas. That CO gas was responsible for the fire fountains that sprayed volcanic glass over parts of the lunar surface.
For many years, the Moon was thought to be devoid of volatiles like hydrogen and carbon. It wasn’t until the last decade or so that volatiles were definitively detected in lunar samples. In 2008, Saal and colleagues detected water in lunar volcanic beads. They followed that discovery with detections of sulfur, chlorine and fluorine. While it became apparent that the Moon was not completely depleted of volatiles as was once thought, none of the volatiles that had been detected were consistent with fire fountain eruptions. For example, if water had been the driving force, there should be mineralogical signatures in recovered samples. There are none.
For this research, Saal and his colleagues carefully analyzed glass beads brought back to Earth from the Apollo 15 and 17 missions. In particular, they looked at samples that contained melt inclusions, tiny dots of molten magma that became trapped within crystals of olivine. The crystals trap gases present in the magma before they can escape.
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Volcanic evidence
Super-tiny bits of molten magma became trapped in tiny crystals of olivine, preserving evidence of volatile gasses.  Saal lab/Brown University
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Although other volatiles were previously detected in the lunar volcanic glasses and melt inclusions, the measurement of carbon remained elusive due to the high detection limits of the available analytical techniques. Erik Hauri from Carnegie Institution for Science developed a state-of-the-art ion probe technique reducing the detection limits of carbon by two orders of magnitude. That allows a measurement of as low as 0.1 part per million.
“This breakthrough depended on the ability of Carnegie’s NanoSIMS ion probe to measure incredibly low levels of carbon, on objects that are the diameter of a human hair,” said Hauri. “It is really a remarkable achievement both scientifically and technically.”
The researchers probed the melt inclusions using secondary ion mass spectroscopy. They calculated that the samples contained initially 44 to 64 parts per million carbon. Having detected carbon, the researchers devised a theoretical model of how gases would escape from lunar magma at various depths and pressures, calibrated from the results of high-pressure lab experiments. The model had long been used for Earth. Saal and colleagues changed several parameters to match the composition and conditions affecting lunar magma.
The model showed that carbon, as it combines with oxygen to form CO gas, would have degassed before other volatiles.
“Most of the carbon would have degassed deep under the surface,” Saal said. “Other volatiles like hydrogen degassed later, when the magma was much closer to the surface and after the lava began breaking up into small globules. That suggests carbon was driving the process in its early stages.”
In addition to providing a potential answer to longstanding questions surrounding lunar fire fountains, the findings also serve as more evidence that some volatile reservoirs in the Moon’s interior share a common origin with reservoirs in the Earth, the researchers say.
The amount of carbon detected in the melt inclusions was found to be very similar to the amount of carbon found in basalts erupted at Earth’s mid-ocean ridges. Saal and his colleagues have shown previously that Earth and the Moon have similar concentrations of water and other volatiles. They have also shown that hydrogen isotope ratios from lunar samples are similar to that of Earth.
If volatile reservoirs on the Earth and Moon do indeed share a common source, it has implications for understanding the Moon’s origin. Scientists believe the Moon formed when Earth was hit by a Mars-size object very early in its history. Debris from that impact accreted to form the Moon.
“The volatile evidence suggests that either some of Earth’s volatiles survived that impact and were included in the accretion of the Moon or that volatiles were delivered to both the Earth and Moon at the same time from a common source — perhaps a bombardment of primitive meteorites,” Saal said.
Other authors on the paper were Diane Wetzel, a graduate student at Brown, and Malcolm Rutherford, professor of geological sciences. The study was supported by NASA’s LASER program (NNX08AY97G and NNX11AB27G), NASA’s Cosmochemistry program (NNX12AH62G), the Deep Carbon Observatory, and the Carnegie Institution of Washington.
Quelle: Brown University

Tags: Astronomie 

1667 Views

Samstag, 29. August 2015 - 21:14 Uhr

Astronomie - Interstellare Samen könnten Oasen des Lebens schaffen

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We only have one example of a planet with life: Earth. But within the next generation, it should become possible to detect signs of life on planets orbiting distant stars. If we find alien life, new questions will arise. For example, did that life arise spontaneously? Or could it have spread from elsewhere? If life crossed the vast gulf of interstellar space long ago, how would we tell?
New research by Harvard astrophysicists shows that if life can travel between the stars (a process called panspermia), it would spread in a characteristic pattern that we could potentially identify.
"In our theory clusters of life form, grow, and overlap like bubbles in a pot of boiling water," says lead author Henry Lin of the Harvard-Smithsonian Center for Astrophysics (CfA).
There are two basic ways for life to spread beyond its host star. The first would be via natural processes such as gravitational slingshotting of asteroids or comets. The second would be for intelligent life to deliberately travel outward. The paper does not deal with how panspermia occurs. It simply asks: if it does occur, could we detect it? In principle, the answer is yes.
The model assumes that seeds from one living planet spread outward in all directions. If a seed reaches a habitable planet orbiting a neighboring star, it can take root. Over time, the result of this process would be a series of life-bearing oases dotting the galactic landscape.
"Life could spread from host star to host star in a pattern similar to the outbreak of an epidemic. In a sense, the Milky Way galaxy would become infected with pockets of life," explains CfA co-author Avi Loeb.
If we detect signs of life in the atmospheres of alien worlds, the next step will be to look for a pattern. For example, in an ideal case where the Earth is on the edge of a "bubble" of life, all the nearby life-hosting worlds we find will be in one half of the sky, while the other half will be barren.
Lin and Loeb caution that a pattern will only be discernible if life spreads somewhat rapidly. Since stars in the Milky Way drift relative to each other, stars that are neighbors now won't be neighbors in a few million years. In other words, stellar drift would smear out the bubbles.
This research has been accepted for publication in The Astrophysical Journal Letters.
Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.
Quelle: CfA

Tags: Astronomie 

1705 Views

Samstag, 29. August 2015 - 15:15 Uhr

Raumfahrt - Start von Roskosmos Proton-Trägerrakete mit British communications satellite Inmarsat 5 F3

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4.08.2015

The Russian Federal Space Agency Roscosmos plans to carry out six launches of a Proton-M launch vehicle within the next four months, one of them for the Defense Ministry, a Russian space rocket industry source told Interfax-AVN on Monday.
"Roscosmos has already announced a Proton-M launch carrying the British communications satellite Inmarsat 5 F3, scheduled for August 28. In addition, the launch of a Proton-M carrying an Express-AM8 communications satellite is planned for September 14, and the Turkish spacecraft Turksat 4B is to be put into orbit on October 6. In addition, another launch in the Defense Ministry's interests will take place in October," the source said.
Roscosmos plans also to launch two Proton vehicles in November to put the Eutelsat 9B and Express-AMU-1 telecommunications satellites into orbit, he said.
The Proton launches were suspended following the crash of such a vehicle carrying a Mexican telecommunications satellite in May 2015.
The Khrunichev space research and production center had reported earlier that the launches of Proton rockets would be resumed following the May crash on August 28 by sending the British telecommunications satellite Inmarsat 5 F3 into space.
Proton missions were suspended following the failed launch of a Mexican communications satellite in May 2015. A Proton-M rocket with a Briz-M upper stage and the MexSat-1 Mexican communication satellite onboard blasted off from Baikonur on May 16. The engine of the rocket's upper stage shut down during the 498th second of the flight, reportedly above the Transbaikal territory at an altitude of about 161 kilometers, one minute before the payload was to separate from the launch vehicle. "The third stage, the upper stage, and the spacecraft burned up in the atmosphere," Roscosmos said.
A government commission investigating the crash concluded that the failed Proton-M mission was due to the failure of the 3rd stage's thruster because of increased vibration caused by the misbalance of the turbo-pump unit's rotor, whose performance was affected by high temperatures and an imperfect balance system. The commission also said in its conclusions that the crash was caused by the design factor.
Quelle: Interfax
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ILS CONCLUDES THE REVIEW OF THE CENTENARIO PROTON LAUNCH FAILURE INVESTIGATION
The International Launch Services (ILS) Failure Review Oversight Board (FROB) concluded its work, concurring with the most probable cause and the associated corrective action plan which were identified by the Russian Interagency Commission (IAC) as a result of the May 16 Proton launch vehicle failure carrying the Centenario spacecraft.
The members of the FROB reviewed the findings and conclusions from the IAC along with results from testing and investigations that the IAC directed to be performed by Khrunichev and their subsidiaries. 
Based on the data presented by KhSC, the FROB agreed that the most probable cause of the failure was a result of a higher than expected vibration environment most likely caused by the combination of a marginal mechanical joint used to mount the Stage III steering engine turbo pump and a steering engine turbopump rotor material that had marginal strength under maximum operating environments. This led to a premature shutdown of the turbopump and loss of Stage III control authority and subsequently to the failure of the mission during 3rd stage operation approximately 497 seconds after liftoff.
“The participating customers, insurance underwriters and independent subject matter experts are to be commended for their valuable contributions during the extensive FROB review process. We thank our customers for their support as we prepare for the safe return to flight of ILS Proton,” said ILS Vice President and Chief Technical Officer, John Palmé.
Quelle: ILS
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Update: 28.08.2015
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Proton-M rocket to be launched from Baikonur first time after May crash
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The carrier rocket will orbit the British telecommunications satellite Inmarsat-5F3
Russia’s Proton-M rocket will be launched on Friday for the first time after the May crash from the Baikonur cosmodrome in Kazakhstan. The carrier rocket will orbit the British telecommunications satellite Inmarsat-5F3, the press service of the Khrunichev State Research and Production Space Centre, which makes the Protons, told TASS.
"The launch is scheduled for 14:44 pm, Moscow time on August 28," the company said.
The separation of the upper stage - the satellite with the Briz-M booster - is to take place nine minutes after the launch, at 14:53 pm, Moscow time.
After that the satellite will be placed into orbit by means of five burns of the Briz-M’s sustainer engine and is expected to separate from the booster in some 12 hours after the blast-off - at 02:44 am, Moscow time on August 29.
The UK satellite had been planned to be orbited in late May, but the launch was postponed due to the Proton-M rocket accident, which took place on May 16 - exactly one year after a similar incident. A Mexican telecommunications satellite was lost in the abortive launch. The Russian Federal Space Agency (Roscosmos) arrived at the conclusion that the accident was caused by a design defect that had led to a Proton fall back in 1988.
Inmarsat-5F3 is a fifth-generation telecommunications satellite of the international satellite operator Inmarsat. It was manufactured by the American company Boeing. The satellite will join the Global Express new global system of mobile satellite services, which will consist of four satellites and six Inmarsat ground stations. The company will invest $1.2 billion in its infrastructure and space segment.
To date, two satellites of the new system have been launched. The first - Inmarsat-5F1 - was launched in late 2013. Its ··coverage area includes Europe, the Middle East, Africa and Asia. The Inmarsat-5F2 satellite is to provide telecommunications services in North America and South America and in the Atlantic. The third satellite will provide communications services to the Pacific region.
Quelle: TASS
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Quelle: Roscosmos
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Update: 14.20 MESZ
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Erfolgreicher Start von Proton mit Inmarsat-5
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Quelle: ILS
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Update: 29.08.2015
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ILS PROTON SUCCESSFULLY LAUNCHES INMARSAT-5 F3 SATELLITE
The Final Global Xpress®Satellite Launch in 3-constellation Series
BAIKONUR COSMODROME, Kazakhstan, August 29, 2015 – An International Launch Services (ILS) Proton Breeze M successfully placed the Inmarsat-5 F3 (I-5 F3) satellite into a super-synchronous transfer orbit (SSTO) today. The spacecraft was launched for Inmarsat, the leading provider of global mobile satellite communications services. I-5 F3 is the third of Inmarsat’s next-generation Global Xpress satellites, which launched on an ILS Proton. This marks the third Proton launch of the year and the 5th SSTO mission for ILS, a leader in providing launch services to the global commercial satellite industry.
The Proton launch vehicle, carrying the I-5 F3 satellite, lifted off from Pad 39 at the Baikonur Cosmodrome yesterday at 17:44 local time (12:44, London time, 11:44 GMT and 07:44 ET). The SSTO mission utilized a 5-burn Breeze M mission design to advance the orbital unit first to a circular parking orbit, then to an intermediate orbit, followed by a transfer orbit, and finally to a 65,000 km-apogee super-synchronous transfer orbit. After a 15-hour, 31-minute mission, the satellite was placed into the target orbit by the Proton launcher. SSTO missions provide increased heavy-lift performance over GTO mission designs, allowing our customers the capability to maximize spacecraft operational lifetime.
 
The satellite was manufactured by Boeing Satellite Systems International and built on the reliable 702HP platform. Weighing over 6 metric tons at lift-off, the I-5 F3 satellite has 89 Ka-band fixed beams and 6 steerable ones. I-5 F3 is designed to generate approximately 15 kilowatts of power at the start of service and approximately 13.8 kilowatts at the end of its 15-year design life. To generate such high power, the spacecraft's two solar wings employ five panels of ultra-triple-junction solar cells.
Global Xpress will be the first globally available high-speed mobile broadband network, delivered through a single provider.  It will offer the unique combination of global coverage, consistent high-speed performance, and the network reliability for which Inmarsat is renowned. GX services will be deployed to serve the advanced mobility needs of Inmarsat’s existing customers on land, at sea and in the air, will diversify Inmarsat’s business into existing adjacent government and energy markets, and position Inmarsat in the vanguard of new, high-growth military-Ka,  aviation passenger, maritime and other connectivity markets.
ILS President Phil Slack stated, “It is always exciting to launch a satellite for one of our customers and to play a key role in the deployment of its services. As the launch provider for Inmarsat’s first three Global Xpress satellites, it has been extremely rewarding to know that we have helped to enable Inmarsat’s innovative technology.  Inmarsat’s Global Xpress network delivers broadband connectivity to the remotest regions of the world, as well as critical worldwide communications services on land, at sea or in the air. The collective teams at Inmarsat, ILS, Khrunichev and Boeing are to be commended for their dedication to the successful launch of Inmarsat-5 F3.”
“The launch of the third Global Xpress satellite is a pivotal moment in Inmarsat’s history. Global Xpress will delivery broadband speeds an order of magnitude faster than our 4th generation (I-4) constellation, allowing us to offer our current customers new high value services and solutions and to grow our business activities into exciting new markets. This is truly a new era in mobile satellite communications,” said Rupert Pearce, CEO, Inmarsat. “We sincerely thank our dedicated staff and our partners at Inmarsat, Boeing, ILS and Khrunichev for ensuring mission success.”
The I-5 F3 launch marked the 405th launch for Proton since its maiden flight in 1965 and the 90th ILS Proton Launch overall. This was also the 19th Boeing-built satellite launched on an ILS Proton and the 5th Inmarsat satellite launched on Proton overall. The Proton M Breeze M vehicle is developed and built by Khrunichev Research and Production Space Center of Moscow, Russia’s premier space industry manufacturer and majority shareholder in ILS.
Quelle: ILS

Tags: Raumfahrt 

1459 Views

Samstag, 29. August 2015 - 14:30 Uhr

UFO-Forschung - Wenn der gesunde Menschenverstand ausgeschaltet wird...

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Curiosity fotografiert «Raumschiff»
War der Mars ein Schlachtfeld?
MARS - War der rote Planet einst Schauplatz einer epischen galaktischen Schlacht? UFO-Experten wollen in neusten Aufnahmen der Nasa vom Mars Anzeichen dafür gefunden haben.
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Solche Schlagzeilen umkreisen den Planet Erde durch die Schlagzeilen-Medienwelt und man fragt sich eigentlich WARUM?
Schaut man sich das nachfolgende Original-Foto von Mars-Rover Curiosity an, ist dies ein Felsengestein wie all die anderen Gesteine welche auf dem Mars herum liegen:
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Selbst wenn man das Sonnelicht/Schattenspiel als Ursache für etwaige Auslegungen für Raumschiff tollerieren würde, stellt sich die Frage zur Größe und man wird es einfach Leid über so einen künstlich hochgebauschten Quatsch sich weiter  einen Kopf zu machen.
Aber WARUM findet so ein Quatsch überhaupt statt? Liegt es nicht auch daran, weil genau die internationale Ufologen-Gemeinde den permanenten Mangel an Beweisen damit vertuschen will? Wie sonst kann man sich "das große Schweigen der Lämmer" in der Ufologen-Szene  dazu erklären? Man schreibt sich gerade auch in unserem Lande sich die möglichst seriösten, wissenschaftlichsten und kompetenteste UFO-Forschung  zu, dennoch sitzt man auf unsäglich vielen Good-Ufo-Fällen welche eigentlich gar keine sind. Man selbst dies weiss aber nicht die Courage hat sie neu zu bewerten und der Öffentlichkeit so mit nicht weiter ein verfälschtes UFO-Bild zu zeichnen. Man verbündet sich mit Ufologengruppen unter einander und feiert dies als neuer Anfang vom Alten!
Man veröffentlicht theoretische Abhandlungen über UFO-Forschung und verwendet sie selbst nicht, hat zwar einen über Jahre entstandenen Fragebogen und verwendet ihn nicht, man hat Meldestellen welche nicht besetzt sind und die Melder wie beim Postamt der 60iger behandelt werden. Fälle die falsch oder gar nicht recherchiert wurden und nur spekuliert wurde, werden trotz Einwände nicht neu aufgerollt, trotz Zusage. 
All diese unbequemen Punkte sind die "selbstgemachten Probleme der UFO-Szene" wie sie derzeit sind bzw. schon immer waren! 
CENAP-Mannheim, hjkc

Tags: UFO-Forschung 

1597 Views

Samstag, 29. August 2015 - 09:44 Uhr

Raumfahrt - NASA New Horizons-Team wählt neues potenzielles Kuiper-Gürtel Flyby Ziel

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Artist's impression of NASA's New Horizons spacecraft encountering a Pluto-like object in the distant Kuiper Belt. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Steve Gribben)

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NASA has selected the potential next destination for the New Horizons mission to visit after its historic July 14 flyby of the Pluto system. The destination is a small Kuiper Belt object (KBO) known as 2014 MU69 that orbits nearly a billion miles beyond Pluto.
This remote KBO was one of two identified as potential destinations and the one recommended to NASA by the New Horizons team. Although NASA has selected 2014 MU69 as the target, as part of its normal review process the agency will conduct a detailed assessment before officially approving the mission extension to conduct additional science.
“Even as the New Horizon’s spacecraft speeds away from Pluto out into the Kuiper Belt, and the data from the exciting encounter with this new world is being streamed back to Earth, we are looking outward to the next destination for this intrepid explorer,” said John Grunsfeld, astronaut and chief of the NASA Science Mission Directorate at the agency headquarters in Washington. “While discussions whether to approve this extended mission will take place in the larger context of the planetary science portfolio, we expect it to be much less expensive than the prime mission while still providing new and exciting science.”
Like all NASA missions that have finished their main objective but seek to do more exploration, the New Horizons team must write a proposal to the agency to fund a KBO mission. That proposal – due in 2016 – will be evaluated by an independent team of experts before NASA can decide about the go-ahead.
Early target selection was important; the team needs to direct New Horizons toward the object this year in order to perform any extended mission with healthy fuel margins. New Horizons will perform a series of four maneuvers in late October and early November to set its course toward 2014 MU69 – nicknamed “PT1” (for “Potential Target 1”) – which it expects to reach on January 1, 2019. Any delays from those dates would cost precious fuel and add mission risk.
“2014 MU69 is a great choice because it is just the kind of ancient KBO, formed where it orbits now, that the Decadal Survey desired us to fly by,” said New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute (SwRI) in Boulder, Colorado. “Moreover, this KBO costs less fuel to reach [than other candidate targets], leaving more fuel for the flyby, for ancillary science, and greater fuel reserves to protect against the unforeseen.”
New Horizons was originally designed to fly beyond the Pluto system and explore additional Kuiper Belt objects. The spacecraft carries extra hydrazine fuel for a KBO flyby; its communications system is designed to work from far beyond Pluto; its power system is designed to operate for many more years; and its scientific instruments were designed to operate in light levels much lower than it will experience during the 2014 MU69 flyby.
The 2003 National Academy of Sciences’ Planetary Decadal Survey (“New Frontiers in the Solar System”) strongly recommended that the first mission to the Kuiper Belt include flybys of Pluto and small KBOs, in order to sample the diversity of objects in that previously unexplored region of the solar system. The identification of PT1, which is in a completely different class of KBO than Pluto, potentially allows New Horizons to satisfy those goals.
But finding a suitable KBO flyby target was no easy task. Starting a search in 2011 using some of the largest ground-based telescopes on Earth, the New Horizons team found several dozen KBOs, but none were reachable within the fuel supply aboard the spacecraft.
The powerful Hubble Space Telescope came to the rescue in summer 2014, discovering five objects, since narrowed to two, within New Horizons’ flight path. Scientists estimate that PT1 is just under 30 miles (about 45 kilometers) across; that’s more than 10 times larger and 1,000 times more massive than typical comets, like the one the Rosetta mission is now orbiting, but only about 0.5 to 1 percent of the size (and about 1/10,000th the mass) of Pluto. As such, PT1 is thought to be like the building blocks of Kuiper Belt planets such as Pluto.
Unlike asteroids, KBOs have been heated only slightly by the Sun, and are thought to represent a well preserved, deep-freeze sample of what the outer solar system was like following its birth 4.6 billion years ago.
“There’s so much that we can learn from close-up spacecraft observations that we’ll never learn from Earth, as the Pluto flyby demonstrated so spectacularly,” said New Horizons science team member John Spencer, also of SwRI. “The detailed images and other data that New Horizons could obtain from a KBO flyby will revolutionize our understanding of the Kuiper Belt and KBOs.” The New Horizons spacecraft – currently 3 billion miles [4.9 billion kilometers] from Earth – is just starting to transmit the bulk of the images and other data, stored on its digital recorders, from its historic July encounter with the Pluto system. The spacecraft is healthy and operating normally.
New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Ala. The Johns Hopkins University Applied Physics Laboratory in Laurel, Md., designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning.
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Path of NASA's New Horizons spacecraft toward its next potential target, the Kuiper Belt object 2014 MU69, nicknamed "PT1" (for "Potential Target 1") by the New Horizons team. Although NASA has selected 2014 MU69 as the target, as part of its normal review process the agency will conduct a detailed assessment before officially approving the mission extension to conduct additional science. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute/Alex Parker)
Quelle: NASA

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Freitag, 28. August 2015 - 14:15 Uhr

Raumfahrt - Erste Signale von Calet auf der ISS

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After berthing with the ISS, CALET was extracted by robotic arm from the Japanese HTV-5 transfer vehicle and installed on the Japanese Exposure Facility (right) where it will start its first data-taking (Image: NASA/JAXA)
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Five days after it launched from the Tanegashima Space Center on board the HTV-5 Transport Module, operated by the Japan Aerospace Exploration Agency (JAXA), the CALorimetric Electron Telescope (CALET) docked at the International Space Station (ISS). The instrument, now in the check-out phase, is sending its first signals back from the Space Station.
CALET is the space mission lead by JAXA with the participation of the Italian Space Agency (ASI) and NASA. It is a CERN recognized experiment and the second high-energy astroparticle experiment to be installed on the ISS after AMS-02, which is taking data from the remote station since 2011. Designed as a space observatory for long-term observations of cosmic radiation aboard the external platform JEM-EF of the Japanese module (KIBO) on the ISS, CALET aims at identifying electrons, nuclei and gamma-rays coming from space and measure their energies with high-resolution. “One of the main scientific objectives of CALET is to measure the detailed shape of the electron spectrum above 1 TeV,” says Shoji Torii of Waseda University in Tokyo, Principal Investigator (PI) of  CALET. “This unexplored region is gaining a growing interest by the scientific community as it might be able to show for the first time the smoking gun of the presence of nearby astronomical source(s) where electrons are accelerated. We know that electrons cannot travel for long distances as they quickly lose their energy. Therefore, they are expected to originate relatively near to Earth – about 1 Kpc.”
CALET will perform accurate measurements of the electron energy spectrum from 1 GeV to 20 TeV. “The high end of the spectrum could be particularly interesting as it could help resolve the controversial interpretation of the electron and positron spectra measured by AMS-02 and could provide a clue on possible signatures of dark matter,” says John Wefel of Louisiana State University, Co-PI of the CALET project and lead of the American team participating in CALET.
CALET could also help explain the deviation from a pure power-law that was recently observed by the AMS-02 collaboration in the energy spectra of light nuclei. “Thanks to its excellent energy resolution and ability to identify cosmic nuclei from hydrogen to iron and above,” says Pier Simone Marrocchesi, Co-PI of the CALET collaboration and head of the Italian team. “CALET will be able to extend the present data to higher energies and measure accurately the curvature of the spectrum and the position of the spectral break-point for individual nuclear species. The calibration of the two calorimetric instruments is the key to control the energy scale and this is why we performed several calibration tests at CERN.”
After berthing with the ISS, CALET was extracted by a robotic arm from the Japanese H-II transfer vehicle (HTV5) and installed on the JEM-EF where it will start a first data-taking period of 5 years.
Quelle: CERN

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