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Sonntag, 12. Januar 2014 - 18:18 Uhr

Planet Erde - Valencia / Spanien bei Nacht

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Valencia

Valencia, Spain, seen from over 300 km above Earth by an astronaut on the International Space Station on 6 October 2013. This incredibly sharp image shows the grid-like streets of Valencia surrounding the older, less-structured, centre. The ‘claw’ extending to the top is the port of Valencia that serves as a breakwater as well as a platform to offload ships.

Lights of a ship that is either leaving or arriving at the port can be seen. The blackness to the top left of this image is the Mediterranean Sea where no streetlights exist. Other areas of blackness are parks and countryside, places where humans have not settled and installed artificial lights.

The bright blue lights to the bottom of the image are from Valencia’s airport and industrial sites.

Credits: ESA/NASA

Tags: Valencia Spain 

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Sonntag, 12. Januar 2014 - 18:00 Uhr

Astronomie - Hubble sieht einen Stern beim Auflöse-Prozess

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Hubble Sees a Star Set to Explode

Floating at the center of this new Hubble image is a lidless purple eye, staring back at us through space. This ethereal object, known officially as [SBW2007] 1 but sometimes nicknamed SBW1, is a nebula with a giant star at its center. The star was originally twenty times more massive than our sun, and is now encased in a swirling ring of purple gas, the remains of the distant era when it cast off its outer layers via violent pulsations and winds.

But the star is not just any star; scientists say that it is destined to go supernova. Twenty-six years ago, another star with striking similarities went supernova — SN 1987A. Early Hubble images of SN 1987A show eerie similarities to SBW1. Both stars had identical rings of the same size and age, which were travelling at similar speeds; both were located in similar HII regions; and they had the same brightness. In this way SBW1 is a snapshot of SN1987a's appearance before it exploded, and unsurprisingly, astronomers love studying them together.

At a distance of more than 20 000 light-years it will be safe to watch when the supernova goes off. If we are very lucky it may happen in our own lifetimes.

Quelle: NASA


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Sonntag, 12. Januar 2014 - 17:30 Uhr

Raumfahrt - Erfolgreicher Antares-Start mit Orbital Cygnus ORB-1

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Antares rocket launch, U.S. Cargo Ship Launches to ISS on First Resupply Mission, January 9, 2014

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Orbital Sciences Corp. launched its Cygnus cargo spacecraft aboard its Antares rocket at 1:07 p.m. EST Thursday from Launch Pad 0A at NASA’s Wallops Flight Facility in Virginia. Cygnus is now traveling 17,500 mph in Earth's orbit to rendezvous with the International Space Station on Sunday, Jan. 12, for the Orbital-1 cargo resupply mission.
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Frams: NASA-TV
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Update: 10.01.2014
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Orbital Successfully Launches Antares Rocket Carrying Cygnus Spacecraft on Cargo Resupply Mission to International Space Station
-- Company Completes Third Successful Antares Launch in the Past Nine Months --

(Dulles, VA 9 January 2014) – Orbital Sciences Corporation (NYSE: ORB), one of the world’s leading space technology companies, today announced it successfully launched its Antares™ medium-class rocket carrying the first of eight Cygnus™ cargo logistics spacecraft missions to the International Space Station (ISS) as part of its $1.9 billion Commercial Resupply Services (CRS) contract with NASA. The launch of Orbital’s Antares rocket and Cygnus cargo logistics spacecraft will culminate in rendezvous and berthing with the ISS on Sunday, January 12 at approximately 6:00 a.m. (EST). Cygnus will deliver approximately 2,780 lbs. (1,260 kg.) of cargo to the Expedition 38 astronauts and remain attached to the station until February 18 before departing with approximately 2,800 lbs. (1,300 kg.) of disposable cargo for a safe, destructive reentry over the Pacific Ocean.

Lift-off of Orbital’s Antares rocket occurred today at 1:07 p.m. (EST) from NASA’s Wallops Flight Facility in eastern Virginia. Following a 10-minute ascent, the Cygnus spacecraft was successfully deployed by the Antares upper stage and placed into its intended orbit of about 135 x 175 miles (220 X 280 km) above the Earth, inclined at 51.6 degrees to the equator. Approximately 25 minutes later, Orbital’s engineering team confirmed that reliable communications had been established and that the solar arrays were fully deployed, providing the necessary electrical power to command the spacecraft.

“It was another excellent launch of Antares, and so far, our first CRS mission is off to a great start with Cygnus operating exactly as anticipated at this early stage of the mission,” said Mr. David W. Thompson, Orbital’s President and Chief Executive Officer. “Our team has put in a lot of hard work to get to the point of performing regular ISS cargo delivery trips for NASA. It’s an exciting day for all of us and I’m looking forward to completing this and our future CRS missions safely and successfully for our NASA customer.”

Under a $1.9 billion CRS contract with NASA, Orbital will use Antares and Cygnus to deliver up to 44,000 pounds (20,000 kilograms) of cargo to the ISS over eight missions through late 2016. For these missions, NASA will manifest a variety of essential items based on ISS program needs, including food, clothing, crew supplies, spare parts and equipment, and scientific experiments.

Orbital privately developed the Antares launch vehicle to provide low-cost, reliable access to space for medium-class payloads. It is the largest and most complex rocket the company has ever produced. Under the Commercial Orbital Transportation Services (COTS) joint research and development initiative with NASA, Orbital also developed the Cygnus spacecraft, which is an advanced maneuvering vehicle that meets the stringent human-rated safety requirements for ISS operations. Together, these products showcase Orbital’s ability to apply rigorous engineering approaches and commercial business practices to significantly shorten development timelines and lower operational costs of sophisticated space systems as compared to traditional government-run programs.

Quelle: Orbital

Update:
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Planet Labs’ mini-satellites take flight toward the International Space Station

The Antares rocket that launched today to journey to the International Space Station contained 2,780 pounds of cargo, including food, spare parts and even a colony of ants for a science experiment. It also held the future of Earth imaging: 28 “Dove” satellites the size of shoe boxes that will help San Francisco startup Planet Labs. build a constantly-updating view of our world.
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The “flock,” as Planet Labs calls it, is the largest group of satellites ever deployed. They will send back images of the Earth down to the three to five meter scale, which is close enough to “count trees, but not see people,” co-founder Robbie Schingler told me in July. The images can be bought for a fee to track things like agricultural yield, a cargo ship’s progress across the ocean or even how much deforestation occurs in a country each year.
The satellites will sit on the ISS for the month of January before being deployed. They are expected to begin sending images to Planet Labs headquarters as early as February. They are funded in part by the $52 million in Series B funding the company received last month.
The Antares rocket is operated by Orbital Sciences Corp., one of two private space companies NASA has tasked with carrying supplies to the ISS. This is the first of eight cargo missions that will carry on through 2016. The rocket that launched today is expected to dock at the ISS Sunday.
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Quelle: GIGAOM
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SF Startup Launches Eyes in the Sky

Engineers from startup Planet Labs huddled over pancakes and mimosas Thursday morning, staring at a projector screen in their San Francisco office as their “doves” took flight. The doves, as they are known to Planet Labs employees, are 28 small satellites stuffed in the cargo section of a rocket taking off from a NASA base in Virginia.
The launch of the satellites, each slightly bigger than a rolled-up movie poster, is the culmination of Planet Labs’ three-year effort to build the world’s largest privately owned fleet of earth-imaging satellites. After they are released from the International Space Station in the coming weeks, the satellites will orbit the earth at an altitude of 400 kilometers – about 249 miles – constantly taking pictures of the entire planet.
This year promises to be a big one for the burgeoning microsatellite industry. Thanks to technological innovations that have enabled satellites to be built smaller and cheaper, a handful of startups is entering this new space race with an eye towards new commercial uses for satellite imagery.
In addition to Planet Labs, two other earth-imaging startups have recently emerged from stealth mode: UrtheCast, which plans to stream video from the Russian section of the International Space Station; and Skybox, which launched a single, high-resolution imaging satellite in November. The companies have backing from some top venture capitalists, including the Russian entrepreneur Yuri Milner and Khosla Ventures in Silicon Valley.
If building satellites and getting them into orbit aren’t hard enough, each company also faces the challenge of developing a business model to sell these images.
The companies say there’s no shortage of potential clients: mining companies that now rely on planes to check mine conditions; scientists that monitor the movement of rivers; insurance companies and commodity traders who track crops; tropical countries seeking to measure deforestation; and businesses that want to spy on clients or competitors – to see, for example, how many cars are in a retailer’s parking lot to infer sales volumes.
Unlike its larger competitors, Planet Labs also sees a market for its images among everyday consumers, such as a property owner who wants to check on the status of a vacation home. Its low costs and frequent updates could also appeal to nonprofit organizations that could use the images to monitor social unrest.
Today, high-resolution satellite imagery isn’t available for these kinds of routine uses; their images are just too expensive. While lower-resolution photos are available from services like Google Earth and Google Maps, their images are often several years old.
Planet Labs says the company already has more than $13 million in contracts to sell images from the satellites in Thursday’s launch. But the buyers are scientists and others accustomed to handling raw satellite imagery. In order to tap the broader market potential, Planet Labs CEO Chris Boshuizen says, the company has to figure out a pricing model and a way to deliver imagery as a useful product.
For example, counting cars in a parking lot requires not just images, but big-data analytics: software programs that can tell the difference between a car and a tree, instantly count the number of vehicles, identify patterns and track them over time.
“Some of them will say, ‘Give us a hard drive,’ because they have the in-house ability to do their own analysis,” Boshuizen says. “Others just want answers.”
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Quelle: WSJ
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Update: 11.01.2014
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Orbital Sciences' Cygnus capsule chasing International Space Station for Sunday rendezvous

A tiny representation of the sun sneaks through between a truss-based radiator panel and a primary solar array panel on the Earth-orbiting International Space Station in this photograph taken by one of the Expedition 38 crew members. (NASA photo)

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A commercial space capsule is chasing the International Space Station today carrying almost 3,000 pounds of supplies and science experiments. The Cygnus capsule launched by Orbital Sciences Corp. Thursday will rendezvous with the station Sunday morning in a maneuver televised on NASA TV beginning at 5 a.m. CST. The grapple of the capsule by the station's Canadarm2 is set for 6:02 a.m. CST.The capsule was launched Thursday and has already fired its maneuvering rockets four times to home in on the station it is chasing. The station turned on a beacon today that will guide the capsule closer. On board are 2,780 pounds of supplies (provisions and spare parts), grown-up science experiments and 23 student experiments involving 9,000 students on the ground.  Experiments include observations of ants and a study that could lead to better understanding of drug-resistant bacteria.

Quelle: All Alabama

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Update: 12.01.2014 / 14.00 MEZ

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US space freighter Cygnus docking with ISS


The ISS crew is to catch the Cygnus with a 17-metre robotic arm and then the spaceship will be brought to a docking compartment on the U.S. module Harmony
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The docking of a new U.S. space freighter Cygnus with the International Space Station (ISS) began.

The ISS crew is to catch the Cygnus with a 17-metre robotic arm and then the spaceship will be brought to a docking compartment on the U.S. module Harmony.

The rocket Antares has launched the Cygnus to the ISS on January 9 from a NASA spaceport on Wallops Island, Virginia, U.S. Atlantic Coast. At first the rocket launch was scheduled at December 19, 2013, but it was delayed over a malfunction in the cooling system on the U.S. segment of the ISS that made the astronauts going on a spacewalk to eliminate this break. When the malfunction was eliminated, the launch was slated on January 7, but it was delayed at the last moment due to a strong solar storm in the Earth’s magnetic field that threatened the electric equipment of the rocket with breakdowns.

The freight spaceship Cygnus, which like the booster, was created by private U.S. company Orbital Sciences, is delivering more than 1.3 tonnes of different cargoes, including food, water, spare parts, equipment and material for scientific experiments to the crewmembers of the 38th ISS expedition.

Quelle: ITARTASS

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ISS Crew Grapples Cygnus

International Space Station Expedition 38 crew members Michael Hopkins of NASA and Koichi Wakata of the Japan Aerospace Exploration Agency captured the Orbital Sciences Cygnus cargo spacecraft with the station’s robotic arm at 6:08 a.m. EST as the station and the resupply vehicle flew 260 statute miles over the Indian Ocean, northeast of Madagascar. The spacecraft now will be maneuvered by Wakata for Cygnus’ installation onto the Earth-facing port of the station's Harmony module

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LIVE-Frams NASA-TV

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Quelle: NASA

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Update: 17.30 MEZ

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Christmas delivery finally arrives at space station

A fresh batch of supplies and science experiments, including one designed by Florida high school students, has reached the International Space Station.

Expedition 38 astronauts captured Orbital Sciences Corp.'s unmanned Cygnus cargo freighter at 6:08 a.m. EST, three days after its launch from Virginia on an Antares rocket.

Steering a 58-foot robotic arm, astronaut Mike Hopkins snared the barrel-shaped spacecraft carrying nearly 2,800 pounds of supplies as the two vehicles flew 260 miles over the Indian Ocean, travelling 17,500 mph.

Hopkins radioed congratulations to the ground, noting that the Cygnus was the second he'd seen during his three-and-a-half months living on the station, starting with a maiden demonstration mission last fall.

"I think that's very impressive," he said.

Orbital Sciences Corp. was supposed to make the delivery last month, well before Christmas. But the Virginia company had to wait a month. A space station breakdown in mid-December took priority, and NASA bumped the flight to January in order to repair the disabled cooling system at the orbiting outpost. Then frigid weather at the launch site forced a delay. Then a strong solar storm interfered.

The capture this morning completed the first of eight planned Cygnus trips to the station under a $1.8 billion NASA resupply contract.

Astronaut Koichi Wakata of Japan was set to take over the robotic arm's controls to attach the Cygnus to a Harmony node port within a couple of hours.

The crew might have time to open the Cygnus hatch today, to remove the time-sensitive "Ants in Space" experiment, or it could be done Monday.

Another experiment on board was designed by students from West Shore Jr./Sr. High in Melbourne, Fla., one of 17 projects selected by the Student Spaceflight Experiment Project.

The experiment honors their former teacher, Jason Whitworth, who was stricken with amyotrophic lateral sclerosis, or Lou Gehrig's Disease.

The Cygnus is expected to stay berthed at the station for about 40 days.

Unlike SpaceX's Dragon, which has completed two resupply missions under a $1.6 billion contract and is targeting launch of a third next month from Cape Canaveral, the Cygnus will not return to Earth.

Instead it will be packed with trash, freeing up valuable space on the station, and burn up in the atmosphere when its mission is complete.

Quelle: USA Today

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New NASA Science Arrives at Space Station Aboard Orbital Sciences Cygnus Spacecraft

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Orbital Sciences' Cygnus cargo spacecraft, with the moon seen in the background, is moved into installation position by astronauts using a robotic arm aboard the International Space Station Jan. 12. The spacecraft is loaded with 2,700 lbs of vital science experiments, crew provisions, spare parts and other hardware. Cygnus will remain attached to Harmony until a planned unberthing in February sends the spacecraft toward a destructive re-entry in Earth's atmosphere.
Image Credit: 
NASA
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Astronauts aboard the International Space Station Sunday used a robotic arm to capture and attach the Cygnus supply spacecraft, which carried dozens of new science experiments from across the country and the world to the orbiting laboratory. The arrival capped the first successful contracted cargo delivery by Orbital Sciences Corp. of Dulles, Va., for NASA.

Astronaut Mike Hopkins of NASA grappled the spacecraft at 6:08 a.m. EST and Koichi Wakata of the Japan Aerospace Exploration Agency attached Cygnus to the space station's Harmony Node at 8:05 a.m. The Expedition 38 crew members aboard the station will begin unloading the 2,780 pounds (1,261 kilograms) of supplies aboard Cygnus following hatch opening planned for Monday.

The cargo is comprised of vital science experiments, crew provisions, spare parts and other hardware. This includes 23 student-designed science experiments. One newly arrived investigation will study the decreased effectiveness of antibiotics during spaceflight. Another will examine how different fuel samples burn in microgravity, which could inform future design for spacecraft materials.

Orbital's Cygnus was launched on the company's Antares rocket Thursday from the Mid-Atlantic Regional Spaceport Pad 0A at NASA’s Wallops Flight Facility in Virginia. Cygnus will remain attached to Harmony until a planned unberthing in February sends the spacecraft toward a destructive re-entry in Earth's atmosphere.

Orbital Sciences is one of two companies that built and tested new cargo spacecraft under NASA's Commercial Orbital Transportation Services (COTS) program. COTS was completed late last year with an Orbital Sciences demonstration mission to the space station. Space Exploration Technologies (SpaceX), the other company that partnered with NASA under COTS, also is providing commercial resupply services for the agency. U.S. commercial cargo delivery flights to the station help ensure a robust national capability to deliver critical science research to orbit, significantly increasing NASA's ability to conduct new science investigations aboard the only laboratory in microgravity.

In addition to cargo flights, NASA's commercial space partners are making progress toward a launch of astronauts from U.S. soil within the next three years.

The International Space Station is a convergence of science, technology and human innovation that demonstrates new technologies and makes research breakthroughs not possible on Earth. The space station has been continuously occupied since November 2000. In that time, it has been visited by more than 200 people and a variety of international and commercial spacecraft. The space station remains the springboard to NASA's next great leap in exploration, including future missions to an asteroid and Mars.

Quelle: NASA

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Cygnus cargo craft arrives at ISS with West Shore experiment

Orbital Sciences' Cygnus commercial resupply craft is on its final approach before being captured. Credit: NASA TV

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A fresh batch of supplies and science experiments, including one designed by local high school students, has reached the International Space Station.

Expedition 38 astronauts captured Orbital Sciences Corp.’s unmanned Cygnus cargo freighter at 6:08 a.m. EST, three days after its launch from Virginia on an Antares rocket.

Steering a 58-foot robotic arm, astronaut Mike Hopkins snared the barrel-shaped spacecraft carrying nearly 2,800 pounds of supplies as the two vehicles flew 260 miles over the Indian Ocean, travelling 17,500 mph.

Hopkins radioed congratulations to the ground, noting that the Cygnus was the second he’d seen during his three-and-a-half months living on the station, starting with a maiden demonstration mission last fall.

“I think that’s very impressive,” he said.

The capture this morning completed the first of eight planned Cygnus trips to the station under a $1.8 billion NASA resupply contract.

Astronaut Koichi Wakata of Japan was set to take over the robotic arm's controls to attach the Cygnus to a Harmony node port within a couple of hours.

The crew might have time to open the Cygnus hatch today, to remove the time-sensitive "Ants in Space" experiment, or it could be done Monday.

Another experiment on board was designed by students from West Shore Jr./Sr. High in Melbourne, one of 17 projects selected by the Student Spaceflight Experiment Project.

The experiment honors their former teacher, Jason Whitworth, who was stricken with amyotrophic lateral sclerosis, or Lou Gehrig’s Disease.

The Cygnus is expected to stay berthed at the station for about 40 days.

Unlike SpaceX’s Dragon, which has completed two resupply missions under a $1.6 billion contract and is targeting launch of a third next month from Cape Canaveral, the Cygnus will not return to Earth.

Instead it will be packed with trash, freeing up valuable space on the station, and burn up in the atmosphere when its mission is complete.
Quelle: Florida Today
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Orbital's Cygnus Spacecraft Successfully Berths With International Space Station

-- Rendezvous and Berthing Operations of Company’s First Operational Cargo Logistics Mission Proceeded Smoothly --

-- Cargo Unloading to Begin Tomorrow with 37-Day Stay at Station Planned --

 

(Dulles, VA 12 January 2014) – Orbital Sciences Corporation (NYSE: ORB), one of the world’s leading space technology companies, today announced that its Cygnus™ cargo logistics spacecraft successfully completed its rendezvous and approach maneuvers with the International Space Station (ISS) and was grappled and berthed with the station by the Expedition 38 astronaut crew earlier this morning.  After Cygnus was launched into orbit by Orbital’s Antares™ rocket on Thursday, January 9 from NASA’s Wallops Flight Facility, it completed a series of thruster firings and other maneuvers bringing the spacecraft in close proximity to the ISS.  Final approach to the station began at about 3:00 a.m. (EST) this morning, culminating with the station’s robotic arm grappling the spacecraft at 6:08 a.m. when it was about 30 feet (10 meters) from the ISS.  Cygnus was then guided to its berthing port on the nadir side of the ISS’ Harmony module where its installation was completed at 8:05 a.m. 

“Our first mission under the CRS contract with NASA was flawlessly executed by our Antares and Cygnus operations team, from the picture-perfect launch from NASA’s Wallops Flight Facility to the rendezvous, capture and berthing at the space station this morning,” said Mr. David W. Thompson, Orbital’s President and Chief Executive Officer.  “From the men and women involved in the design, integration and test, to those who launched the Antares and operated the Cygnus, our whole team has performed at a very high level for our NASA customer and I am very proud of their extraordinary efforts.”

Cygnus will remain berthed at the ISS until February 18. Cygnus is delivering approximately 2,780 lbs. (1,260 kg.) of cargo and science payloads to the Expedition 38 astronauts.  Either later today or tomorrow, the crew plans to open the Cygnus hatch and make initial ingress into its cargo module.  Cygnus will remain attached to the station for 37 days before departing with approximately 2,800 lbs. (1,300 kg.) of disposable cargo for a safe, destructive reentry over the Pacific Ocean.

Under a $1.9 billion CRS contract with NASA, Orbital will use Antares and Cygnus to deliver up to 44,000 pounds (20,000 kilograms) of cargo to the ISS over eight missions, including the mission currently underway, through late 2016.  For these missions, NASA will manifest a variety of essential items based on ISS program needs, including food, clothing, crew supplies, spare parts and equipment, and scientific experiments.

About Cygnus

Orbital developed the Cygnus cargo spacecraft as part of its COTS joint research and development initiative with NASA.  Cygnus consists of a common Service Module (SM) and a Pressurized Cargo Module (PCM). The SM incorporates avionics, power, propulsion and communications systems already successfully flown aboard dozens of Orbital’s LEOStar™ and GEOStar™ satellites.  The PCM, designed and built by Thales Alenia Space under a subcontract from Orbital, is based on the Multi-Purpose Logistics Module (MPLM) previously used with the Space Shuttle.  With a full load of cargo and fuel, the standard-configuration Cygnus weighs about 5,200 kg at launch and generates 3.5 kw of electrical power while in orbit.  It is capable of extended-duration missions of a year or longer in space.

Quelle: Orbital

 


2753 Views

Samstag, 11. Januar 2014 - 16:45 Uhr

Raumfahrt - SpaceShipTwo durchbricht Schallmauer zum ersten Male bei Testflug

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Scots rocket man Dave Mackay steers Virgin Galactic spaceship past the supersonic barrier for first time

SUTHERLAND-BORN pilot takes SpaceShipTwo to a speed of Mach 1.4 as Richard Branson's dream of a commercial spaceliner moves a major step closer to reality.

A SCOTS rocket man has helped move the dream of commercial space flights a major step closer to reality.

Virgin Galactic’s Chief Pilot Dave Mackay flew the company’s new spaceship past the supersonic barrier for the first time last night, as the latest round of testing was voted a huge success.

The Sutherland-born Scot piloted SpaceShipTwo to a speed of Mach 1.4 by firing the rocket propulsion system in what has been hailed as a huge breakthrough in the bid to bring the commercial spaceliner into operation within the next year.

The flight, at the Mojave Space Port in California, saw Mackay, 56, take controls of the ship at rocket speed for a mission which he described as a dream come true.

He said: “I have watched SS2 evolve over the years into an incredible vehicle that is going to open up space to more people than ever before.

“To be behind the controls and fly it as the rocket ignited is something I will never forget. She flew brilliantly. All the tests went really well and generated vital data that will be used to further fine-tune our operations.”

Testing of the ship will continue as the pioneering company get ready to invite the army of paid up astronaut customers on board for the first time hopefully within the year.

Commenting on the successful test flight, Sir Richard Branson said: “I couldn’t be happier to start the New Year with all the pieces visibly in place for the start of full space flights.

“2014 will be the year when we will finally put our beautiful spaceship in her natural environment of space.

"Today, we had our own Chief Pilot flying another flawless supersonic flight and proving the various systems required to take us safely to space, as well as providing the very best experience while we’re up there.”

Virgin Galactic CEO George Whitesides said: “Today’s flight was another resounding success.

“We focused on gathering more transonic and supersonic data, and our chief pilot, Dave, handled the vehicle beautifully. With each flight test, we are progressively closer to our target of starting commercial service in 2014.”

Quelle: Daily Record

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Frams: Virgina Galactic Testflug-Video

Quelle: Virgin Galactic


Tags: Virgin Galactic 

2543 Views

Samstag, 11. Januar 2014 - 14:45 Uhr

Raumfahrt - SpaceShipTwo führt weitere Testflüge in der Mojave durch

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11.12.2013

Sporting shiny new tail booms, SpaceShipTwo lands at the Mojave Air and Space Port after a glide flight. (Credit: Virgin Galactic)

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SpaceShipTwo performed a glide flight over the Mojave this morning. Pilots Mark Stucky of Scaled Composites and Mike Masucci of Virgin Galactic tested the ship’s nitrous oxide dump system before separating from the WhiteKnightTwo carrier aircraft and gliding to a landing at the Mojave Air and Space Port.
SpaceShipTwo had a shiny coating of reflective Kapton on the inboard sections of its two tail booms. The material is designed to allow the ship to manage temperatures from its hybrid engine.
It was SpaceShipTwo’s 30th free flight and 28th glide test. The WhiteKnightTwo mother ship made its 145th flight.
In a Tweet, Virgin Galactic said the next powered flight is coming up “soon.”  SpaceShipTwo flew under power twice earlier this year, first at the end of April and then again in the beginning of September.
Quelle: Parabolic Arc
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Update: 11.01.2014
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Success! SpaceShipTwo hits new heights during rocket test

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Virgin Galactic's SpaceShipTwo fires its rocket engine after separating from its WhiteKnightTwo carrier plane on Friday.
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MOJAVE, Calif. — With Virgin Galactic's chief pilot behind the controls for the first time, the company's SpaceShipTwo plane reached a new high on Friday in its first supersonic rocket-powered test of 2014.

The test at Mojave Air and Space Port was aimed at setting the stage for honest-to-goodness flights into outer space later this year, and eventually for commercial space tours. 

"2014 is our year to do it for real," Mike Moses, a former space shuttle manager who now serves as Virgin Galactic's vice president of operations, told NBC News.

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SpaceShipTwo now has three rocket-powered test flights under its belt, in addition to 28 unpowered gliding flights. This time, Virgin Galactic said the 27-foot-wide winged craft went to an altitude of 71,000 feet — just beating out its previous record of 69,000 feet, set last September. Both tests involved a 20-second engine burn, boosting the plane's speed to a maximum velocity of Mach 1.4.

Moses said SpaceShipTwo went a little higher this time just because the flight profile was slightly different. "I'm sure there's a pilot competition," he joked.

This time around, Virgin Galactic and Mojave-based Scaled Composites, the plane's builder, tested a new reflective coating on the rocket plane's tail booms. The flight also marked the first tryout for a thruster system that's designed to keep the plane on course when it's above the atmosphere. Virgin Galactic said all of the test objectives were met.
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A telescopic view shows SpaceShipTwo firing its hybrid rocket engine.

Virgin flight for chief pilot
Another new twist had to do with the people behind the controls. This was the first time that a Virgin Galactic pilot sat in the cockpit for a rocket-powered flight. During the previous two powered tests, all of the flying was done by Scaled Composites' test pilots.

In a post-flight statement, Virgin Galactic chief pilot David Mackay said the flight was a "dream come true."

"I have watched SS2 evolve over the years into an incredible vehicle that is going to open up space to more people than ever before," Mackay said. “To be behind the controls and fly it as the rocket ignited is something I will never forget. She flew like a champ."

Scaled Composites test pilot Mark Stucky was beside Mackay in the cockpit. Meanwhile, Virgin Galactic's Mike Masucci and Scaled's Mike Alsbury were at the controls of SpaceShipTwo's mothership, WhiteKnightTwo. 

Virgin Galactic's CEO, George Whitesides, said the flight was "another resounding success."

“We focused on gathering more transonic and supersonic data, and our chief pilot, Dave, handled the vehicle beautifully," he said in Virgin's post-flight statement. 

Friday's flight was a scaled-down version of the experience that Virgin Galactic's passengers could enjoy as soon as this year. Almost 700 people, including celebrities like Katy Perry and Justin Bieber, have already made reservations. The current ticket price is $250,000.

For the first leg of the test flight, SpaceShipTwo was slung beneath the twin-fuselage WhiteKnightTwo. The paired planes took off from the Mojave airport at 7:20 a.m. PT (10:20 a.m. ET) and rose to a height of 46,000 feet. Then it was time to unhook SpaceShipTwo for the rocket blast.

Seconds after the release, SpaceShipTwo fired up its hybrid rocket engine and blasted upward and away from WhiteKnightTwo. After the burn, the plane continued coasting into a clear sky while Mackay tried out the thrusters. Then the pilots angled SpaceShipTwo's wings into a configuration designed to ensure a safe, stable descent.

A few minutes later, the wings were straightened again, and the plane glided back to a landing on Mojave's 12,000-foot runway. WhiteKnightTwo made its own landing minutes later.

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The glint of sunrise adds a glow to WhiteKnightTwo's takeoff with SpaceShipTwo on Friday.

Sunrise adds a glow to the scene as WhiteKnightTwo and SpaceShipTwo rise from the Mojave Air and Space Port on Friday.

Step by step to space
Virgin Galactic's test program calls for a step-by-step progression of flights that eventually cross the boundary of outer space, at an altitude of 100 kilometers (62 miles).

At that height, up to six passengers could float free in weightlessness for a few minutes, and look out the windows to see jaw-dropping views of a curving Earth beneath the black sky of space. SpaceShipTwo's pilots would use the thruster system that was tested Friday to maneuver the plane for the best views.


SpaceShipTwo is a scaled-up version of SpaceShipOne, a rocket plane that won the $10 million Ansari X Prize for private spaceflight in 2004 in Mojave and is now hanging in the Smithsonian's National Air and Space Museum.

Although the current test program is being conducted in Mojave, Virgin Galactic's operations are expected to shift to Spaceport America in New Mexico for passenger flights. The company's British-born billionaire founder, Richard Branson, has promised to take a seat along with his son, Sam, on the first passenger flight. 

“I couldn't be happier to start the New Year with all the pieces visibly in place for the start of full spaceflights," Branson said. "2014 will be the year when we will finally put our beautiful spaceship in her natural environment of space."

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Ground workers perform servicing on Virgin Galactic's SpaceShipTwo rocket plane after Friday's test flight.

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Quelle: NBC

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Update:

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SpaceShipTwo flies under power for the third time. (Credit: Ken Brown)

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A couple of exclusive SpaceShipTwo pictures from my friend Ken Brown. We went out and stood atop a mountain that overlooks Koehn Lake, which is where they drop SpaceShipTwo over. The lake is maybe 20 miles north of Mojave as the crow flies.

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SpaceShipTwo lights its engine as WhiteKnightTwo flies overhead. (Credit: Ken Brown)

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Virgin Galactic successfully completed its third rocket-powered supersonic flight of its passenger carrying reuseable space vehicle, SpaceShipTwo, Friday morning in Mojave. Here the spaceship and extra chase plane circle for landing.

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Quelle: Parabolic Arc

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Update:

VIRGIN GALACTIC REACHES NEW HEIGHTS IN THIRD SUPERSONIC TEST FLIGHT

CHIEF PILOT PROVES SPACE SYSTEMS

MOJAVE, Calif. – Today, Virgin Galactic, the world’s first commercial spaceline, which is owned by Sir Richard Branson’s Virgin Group and Abu Dhabi’s aabar Investments PJS, successfully completed the third rocket-powered supersonic flight of its passenger carrying reusable space vehicle, SpaceShipTwo (SS2). In command on the flight deck of SS2 for the first time under rocket power was Virgin Galactic’s Chief Pilot Dave Mackay. Mackay, along with Scaled Composites’ (Scaled) Test Pilot Mark Stucky, tested the spaceship’s Reaction Control System (RCS) and the newly installed thermal protection coating on the vehicle’s tail booms. All of the test objectives were successfully completed.

Today’s flight departed Mojave Air and Space Port at 7:22 a.m. PST with the first stage consisting of the WhiteKnightTwo (WK2) carrier aircraft lifting SS2 to an altitude around 46,000 ft. At the controls of WK2 were Virgin Galactic Pilot Mike Masucci and Scaled Test Pilot Mike Alsbury. On release, SS2’s rocket motor was ignited, powering the spaceship to a planned altitude of 71,000 ft. – SS2’s highest altitude to date – and at a maximum speed of Mach 1.4. SS2’s unique feather re-entry system was also tested during today’s flight.

Two important SS2 systems, the RCS and thermal protection coating, were tested during today’s flight in preparation for upcoming full space flights. The spaceship’s RCS will allow its pilots to maneuver the vehicle in space, permitting an optimal viewing experience for those on board and aiding the positioning process for spacecraft re-entry. The new reflective protection coating on SS2’s inner tail boom surfaces is being evaluated to help maintain vehicle skin temperatures while the rocket motor is firing.

SS2’s propulsion system has been developed by Sierra Nevada Corp and is the world’s largest operational hybrid rocket motor. Although today’s flight saw it burn for a planned 20 seconds, the system has been successfully tested in ground firings to demonstrate performance characteristics and burn time sufficient to take the spaceship and its private astronauts to space.

Commenting on the successful test flight, Sir Richard Branson said: “I couldn’t be happier to start the New Year with all the pieces visibly in place for the start of full space flights. 2014 will be the year when we will finally put our beautiful spaceship in her natural environment of space. Today, we had our own Chief Pilot flying another flawless supersonic flight and proving the various systems required to take us safely to space, as well as providing the very best experience while we’re up there.”

This flight was the third opportunity to see a supersonic, rocket-powered test of the Virgin Galactic system after dozens of successful subsonic test flights. “Today’s flight was another resounding success,” said Virgin Galactic CEO George Whitesides. “We focused on gathering more transonic and supersonic data, and our chief pilot, Dave, handled the vehicle beautifully. With each flight test, we are progressively closer to our target of starting commercial service in 2014.”

For Mackay, the flight was a “dream come true.”

“I have watched SS2 evolve over the years into an incredible vehicle that is going to open up space to more people than ever before,” he said. “To be behind the controls and fly it as the rocket ignited is something I will never forget. She flew brilliantly. All the tests went really well and generated vital data that will be used to further fine-tune our operations.”

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Quelle: Virgin Galactic

 


Tags: SpaceShipTwo 

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Samstag, 11. Januar 2014 - 13:28 Uhr

Raumfahrt - Antares-Rakete startet mit Technik des Sowjet-Mondraketen-Programm

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An NK-33 Rocket Engine Undergoes a Test Fire Outside of Samara, Russia

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Remnants of Soviet Moonshot Bid Revived for Space Launches

MOSCOW, At the height of the Cold War in the once-closed Volga River city of Samara, Soviet engineers labored in vain to build a rocket to send men to the moon.

In 1974, with more than a dozen US astronauts having made that landmark voyage and popular fervor for space travel already declining, the program to develop the heavy-lift N1 launcher was shelved after four explosions during testing.

Four decades later, however, the legacy of that project lives on and the lunar rocket engines that had for decades lain forgotten collecting dust in a warehouse are now being used to resupply the International Space Station and launch satellites.

On Thursday, the NASA-funded Antares rocket powered by a pair of upgraded Soviet lunar engines sent the Cygnus spacecraft on its way to dock with the International Space Station on its first full resupply mission to deliver spare parts, experiments, food and water.

The event was the second of two landmark launches of the engines in as many weeks.

In December, another refurbished version of the same engine powered a new variant of Russia’s venerable Soyuz rocket on its maiden launch, lifting a cluster of research equipment into orbit.The launches are “a testament to the long-term benefits we all continue to reap from the investments made during the space race,” NASA chief historian William P. Barry told RIA Novosti.

The launch of the new Soyuz, called the Soyuz-2.1v, from the forested Plesetsk space center in the northern Arkhangelsk region had suffered repeated delays over concerns of a possible engine malfunction. The delays tested the nerves of Russian space officials who have had to contend with a series of failures in recent years.

The launch ultimately went as planned, placing into orbit two calibration spheres used to assist earth-based radar signals for tracking and a small student satellite jointly manufactured by Samara Aerospace University and the TsSKB Progress factory, which also builds all Soyuz rockets.

The Progress plant dates back to World War II, when dozens of factories were evacuated from the warfront, turning Samara into a hub of the aviation industry.

In the 1960s, Sergei Korolyov, the head of the Soviet space program, defied naysayers by tasking a Samara factory, until that point focused on aircraft engine production, with building rocket engines to carry a cosmonaut to the moon.

The design team, led by Nikolai Kuznetsov, seized on a radical new approach called staged combustion.

“Kuznetsov and his team had to be extremely imaginative, creative and skilled to make the leap from building turbo-prop and jet engines to building a highly efficient, relatively small, but powerful liquid oxygen and kerosene rocket engine,” Barry said. “To have succeeded in this stupendous challenge with the limitations they faced is nothing short of phenomenal.”

The design, which was never fully duplicated in the West, required new metallurgical techniques to protect engine parts from ultra-hot corrosive gases. With the fall of the Soviet Union, Western companies began sniffing around for advanced Soviet technologies on the cheap.

In the early 1990s, California-based aerospace company Aerojet heard about the engines at a Moscow aerospace show and ultimately purchased about 40 of the rocket engines, called the NK-33, for around $1 million apiece.

Aerojet is now selling the leftover engines, updated with modern electronics and thrust control, to Orbital Sciences Corp. for its NASA-funded Antares rocket.

As the US Shuttle fleet was approaching the end of its operating life, Orbital signed a $1.9 billion contract with NASA for eight Antares launches to resupply the International State Station with spare parts, water and food. Two more are slated for later this year.

“The basic idea isn't so hard to grasp – the NK-33-1 engines are very good … The marginal cost of improving them for the current launches is still lower than putting brand new engines on a rocket,” said Asif Siddiqi, a Fordham University history professor who has written several books about the Russian space program.

Siddiqi said that although the stock of NK-33-1 engines – a modification of the NK-33 – could run dry, other engines could take their place.

While no new engines have been built since the Soviet lunar program was canceled 40 years ago, Yelena Merkulova, the head spokesperson for the Kuznetsov company that originally built the engines, said that her company’s main current goal is to restart production of the NK-33.

“Given the fact that the engine repeatedly successfully flew in 2013, there has been interest in the NK-33 among European space agencies in addition to our existing customers,” Merkulova said.

The reliance of the US space program on Soviet-developed hardware is a reflection of a move in the aerospace industry following the end of the Cold War to source parts and expertise from around the world.

“The launcher market is, in fact, far more globalized than generally assumed, particularly if you also look at the component level. With the increased commoditization of space, I assume that the globalization trend will continue to some extent,” said Peter Hulsroj, director of the Vienna-based European Space Policy Institute.

Staged combustion technology was later incorporated into other Russian rocket engines, including the RD-180 developed in the 1990s for the Atlas III and V rockets, which were built by Lockheed Martin and have launched a number of US government reconnaissance satellites.

Technical cooperation still remains hostage to politics, however. Russian media speculated this summer, amid frayed ties between Russia and United States, that Moscow could consider banning the sale of RD-180 rocket engines to the United States, a move that would throw the future of the Atlas program into doubt.

“Like any other area of international cooperation, there are risks of losing control of the technology and permitting advances by competitors, be they states or commercial rivals. The benefits devolve from mutual exchanges, learning from others’ experience and in sharing costs,” Said Mosteshar, director of the London Institute of Space Policy and Law, told RIA Novosti.

Quelle: RIANOVOSTI


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Freitag, 10. Januar 2014 - 22:36 Uhr

Astronomie - Weltpremiere - Planetarium-Show: Milliarden Sonnen - Eine Reise durch die Galaxis

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Wenige Wochen nach dem Start der europäischen Weltraummission Gaia am 19. Dezember 2013 präsentieren knapp dreißig Planetarien und die Europäische Weltraumorganisation ESA ihre zweite gemeinsame Planetarium-Show. "Milliarden Sonnen – Eine Reise durch die Galaxis“ ist ab dem 8. Januar 2014 in Planetarien in Deutschland, der Schweiz, Österreich, Frankreich, Spanien, Polen, der Tschechischen Republik, Griechenland und Russland zu sehen.

 

Die Mission Gaia wird über einen Zeitraum von mindestens fünf Jahren eine Milliarde Sterne ins Visier nehmen und dabei ihre 3D-Position, Helligkeit, Farbe und Bewegung mit bislang unerreicht hoher Genauigkeit vermessen. Dieses eine Prozent aller Sterne in unserer Milchstraße genügt, um erstmals eine präzise, dreidimensionale Karte unserer Galaxie zu erstellen. Die Daten der Gaia-Mission werden über die kommenden Jahrzehnte die Grundlage für die wissenschaftliche Astronomie stellen.

Bis vor wenigen Jahrhunderten war die Astronomie gleichbedeutend mit Astrometrie – der Vermessung und Kartierung der Sterne. Der griechische Astronom Hipparchus von Nicäa hatte im 2. vorchristlichen Jahrhundert die ersten Sternkarten gezeichnet und die mathematischen Grundlagen für die Entfernungsmessung mittels der Parallaxe gelegt.

Doch erst 2000 Jahre später konnte der deutsche Gelehrte Friedrich Wilhelm Bessel mit dieser Methode die erste korrekte Entfernung zu einem Stern bestimmen. Der Durchbruch in der Messgenauigkeit gelang jedoch erst mit Satelliten wie Hipparcos und der kürzlich gestarteten Gaia-Mission.

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Planetarium-Shows: Aufwändig produzierte Großformatfilme

Gaia wird die Genauigkeit von Hipparcos weit übertreffen und dabei 10.000 Mal mehr Sterne vermessen. Mit den Gaia-Daten wird es möglich sein, die Entstehungsgeschichte unserer Galaxie nachzuzeichnen und einen Blick in die Zukunft unserer Milchstraße zu werfen. Die enorme Messgenauigkeit wird nur an Metaphern deutlich: Gaia könnte aus einem Meter Entfernung messen, um wie viel ein menschliches Haar in einer hundertstel Sekunde gewachsen ist.

Da die Gaia-Mission alle Bereiche der Astronomie betrifft, ist sie ein ideales Thema für eine Planetarium-Show. Und weil die Planetarien in der Kette der Wissensvermittlung das Bindeglied zwischen der Didaktik in den Schulen und dem Infotainment in den Medien darstellen, sind sie die idealen Partner für die ESA und ihr Wissenschaftsprogramm.

Planetarium-Shows sind aufwändig produzierte Großformatfilme, die sich nahtlos über die gesamte Kuppel eines Planetariums erstrecken und den Zuschauer komplett in ihre Bilderwelt eintauchen lassen. Die Fulldome-Projektion in extrem hoher Auflösung hat inzwischen fast überall den opto-mechanischen Sternenprojektor abgelöst oder zumindest um das Bewegtbild ergänzt. 

 

Das 45minütige Kuppel-Programm „Milliarden Sonnen – Eine Reise durch die Galaxis“ wurde in Zusammenarbeit mit der Europäischen Weltraumorganisation ESA und Planetarien produziert. Es geht zeitgleich in neun Sprachen an den Start – von der russischen Stadt Ufa im Ural bis zum katalonischen Ort Ager in den Pyrenäen – und wird in 17 deutschen Städten zu sehen sein.

Die Premiere wird am 8. Januar 2014 im Planetarium Hamburg gefeiert. ESA-Wissenschaftler Timo Prusti wird zur Eröffnung einen Vortrag über die Gaia-Mission halten. Milliarden Sonnen ist eine spannende Geschichte mit phänomenalen Bildern und hohem Bildungspotential. Empfehlenswert ab 12 Jahren.

Quelle: ESA


2532 Views

Freitag, 10. Januar 2014 - 22:15 Uhr

Raumfahrt - ISRO will bis 2016 Rover zum Mond senden

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Isro aims to demonstrate its capability to soft-land on the lunar surface with this mission

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Chandrayaan-2 would be launched by a GSLV powered by an indigenously developed cryogenic engine, said the Isro spokesperson.
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New Delhi: The Indian Space Research Organization (Isro) is planning to launch India’s mission to the moon, Chandrayaan-2, by 2016, which would include an orbiter, lander and rover, an Isro spokesperson said on Friday.
Earlier, Isro chairman K. Radhakrishnan had said that the space agency will launch Chandrayaan-2 by 2016-17, according to Press Trust of India.
“Isro aims to demonstrate its capability to soft-land on the lunar surface with this mission,” said the Isro spokesperson.
The broad objectives of the mission would include the extension of scientific experiments carried out by Chandrayaan-1, India’s first mission to the moon which included a lunar orbiter and impacter.
Scientists had last year announced that using data from instruments aboard India’s Chandrayaan-1 spacecraft, they had found evidence of water locked in mineral grains on the surface of the moon.
“Chandrayaan-2 would be launched by a Geosynchronous Satellite Launch Vehicle (GSLV) powered by an indigenously developed cryogenic engine,” said the Isro spokesperson.
Quelle: WSJ

Tags: Isro to send orbiter 

2335 Views

Freitag, 10. Januar 2014 - 13:00 Uhr

Raumfahrt - Raumfahrt-Länder diskutieren über Zusammenarbeit

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Space-faring countries discuss cooperation in U.S.

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Ministers and high-level officials from about 35 space-faring countries, including United States and China, on Thursday gathered in Washington D.C. to discuss international cooperation on space exploration.
The International Space Exploration Forum (ISEF) is the "first- ever ministerial-level meeting to build support for global cooperation in space exploration," said the U.S. State Department, the host of the event.
"We all share a deep stake in extending humanity's reach further into the solar system, advancing innovation further and faster, and extending the benefits of discovery to more people in more places," Deputy Secretary William Burns said. "The question facing us today is whether we can muster the courage and political will to advance space exploration and ensure that cooperation continues to trump competition."
Burns noted that 12 national space agencies have developed a shared roadmap that will result in human missions to the surface of Mars and that the International Space Station has welcomed more than 80 countries to participate in its research.
"We should encourage more countries to participate in the activities of the International Space Station," he said. "The station remains the leading space platform for global research and development. The station is the foundation for future human exploration to an asteroid, the Moon, and ultimately Mars. And it is a lasting testament to how much more we can accomplish together than we can on our own."
ISEF, which builds on a process started at the 2011 High-Level International Space Exploration Dialogue hosted by the European Union, the European Space Agency, and the Italian government in Lucca, a city in central Italy, had participants including ministers and high-level officials from the European Union, Japan, Russia, China, India, the Republic of Korea, Brazil, Nigeria, and Saudi Arabia.
Quelle: Xinhua

2583 Views

Freitag, 10. Januar 2014 - 10:59 Uhr

Astronomie - Überraschende neue Klasse von "Hypergeschwindigkeits Sterne" entdeckt

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Top and side views of the Milky Way galaxy show the location of four of the new class of hypervelocity stars. These are sun-like stars that are moving at speeds of more than a million miles per hour relative to the galaxy: fast enough to escape its gravitational grasp. The general directions from which the stars have come are shown by the colored bands. (Graphic design by Julie Turner, Vanderbilt University. Top view courtesy of the National Aeronautics and Space Administration. Side view courtesy of the European Southern Observatory.)

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An international team of astronomers has discovered a surprising new class of “hypervelocity stars” – solitary stars moving fast enough to escape the gravitational grasp of the Milky Way galaxy.
The discovery of this new set of “hypervelocity” stars was described at the annual meeting of the American Astronomical Society this week in Washington, D.C., and is published in the Jan. 1 issue of the Astrophysical Journal.
“These new hypervelocity stars are very different from the ones that have been discovered previously,” said Vanderbilt University graduate student Lauren Palladino, lead author on the study. “The original hypervelocity stars are large blue stars and appear to have originated from the galactic center. Our new stars are relatively small – about the size of the sun – and the surprising part is that none of them appear to come from the galactic core.”
The discovery came as Palladino, working under the supervision of Kelly Holley-Bockelmann, assistant professor of astronomy at Vanderbilt, was mapping the Milky Way by calculating the orbits of Sun-like stars in the Sloan Digital Sky Survey, a massive census of the stars and galaxies in a region covering nearly one quarter of the sky.
“It’s very hard to kick a star out of the galaxy,” said Holley-Bockelmann. “The most commonly accepted mechanism for doing so involves interacting with the supermassive black hole at the galactic core. That means when you trace the star back to its birthplace, it comes from the center of our galaxy. None of these hypervelocity stars come from the center, which implies that there is an unexpected new class of hypervelocity star, one with a different ejection mechanism.”
Astrophysicists calculate that a star must get a million-plus mile-per-hour kick relative to the motion of the galaxy to reach escape velocity. They also estimate that the Milky Way’s central black hole has a mass equivalent to four million suns, large enough to produce a gravitational force strong enough to accelerate stars to hyper velocities. The typical scenario involves a binary pair of stars that get caught in the black hole’s grip. As one of the stars spirals in toward the black hole, its companion is flung outward at a tremendous velocity. So far, 18 giant blue hypervelocity stars have been found that could have been produced by such a mechanism.
Now Palladino and her colleagues have discovered an additional 20 sun-sized stars that they characterize as possible hypervelocity stars. “One caveat concerns the known errors in measuring stellar motions,” she said. “To get the speed of a star, you have to measure the position really accurately over decades. If the position is measured badly a few times over that long time interval, it can seem to move a lot faster than it really does. We did several statistical tests to increase the accuracy of our estimates. So we think that, although some of our candidates may be flukes, the majority are real.”
The astronomers are following up with additional observations.
The new rogues appear to have the same composition as normal disk stars, so the astronomers do not think that their birthplace was in the galaxy’s central bulge, the halo that surrounds it, or in some other exotic place outside the galaxy.
“The big question is: what boosted these stars up to such extreme velocities? We are working on that now,” said Holley-Bockelmann.
Katharine Schlesinger from the Australian National University, Carlos Allende Prieto from the Universidad de La Laguna in Spain, Timothy Beers from the National Optical Astronomy Observatory in Tucson, Young Sun Lee from New Mexico State University and Donald Schneider from Pennsylvania State University also contributed to the discovery.
The research was supported by funds from the Graduate Assistance in Areas of National Need program, National Science Foundation grants AST 0847696, AST 0607482, Physics Frontier Center grants PHY 0216783, the Aspen Center for Physics, the Alfred P. Sloan Foundation and the U.S. Department of Energy Office of Science.
Quelle: Vanderbilt University · Nashville, Tennessee

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