Sonntag, 1. September 2013 - 18:00 Uhr

Raumfahrt - Erfolgreicher Start von Zenit2-SB mit Amos-4


MOSCOW, September 1  - Russia has orbited an Israeli communications satellite, the Federal Space Agency reported Sunday.

The comsat was launched with the help of a Zenit-2SB carrier rocket at 00:05 Moscow Time Sunday (20:05 GMT Saturday) from the Baikonur space center in Kazakhstan.

The Amos-4 satellite (Afro-Mediterranean Orbital System), manufactured by Israel Aerospace Industries Ltd., separated from the DM-SLB upper stage at 06:50 Moscow Time (02:50 GMT).

It will provide DTH, VSAT and broadband Internet services to consumers in Russia, the Middle East, Southeast and Central Asia.



 VLADIVOSTOK Fireball Was Rocket, Not Meteor – Scientist

VLADIVOSTOK, September 1 – A fireball that lit up the sky over Vladivostok, in Russia’s Far East, on Sunday, was actually created by a Russian rocket stage, not a meteor event, a scientist said.

Witnesses in Vladivostok said they saw a flash of light in the sky that could be a meteor, media reports said. Some of the witnesses claimed the fireball “looked like a plane.”

The timing of the fireball reports coincided with the launch of the Zenit rocket from the Baikonur space center in Kazakhstan on Sunday, Russian astronomer Vladimir Surdin said.

“The photos show that this was an artificial object. It was moving from the west to the east and was witnessed some 20 minutes after the launch,” scientist Surdin, from Stenberg Astronomical Institute in Moscow, said.

Quelle: RIA Novosti


Israeli company successfully launches Amos 4 satellite

Satellite joins Spacecom's Amos 2, Amos 3 and Amos 5; to provide services for Russia and the Middle East.

Israeli company successfully launches Amos 4 satellite

Satellite joins Spacecom's Amos 2, Amos 3 and Amos 5; to provide services for Russia and the Middle East.
Amos 4 satellite launch, August 31, 2013. Photo: Israel Aerospace Industries
Israeli communications company Spacecom has successfully launched a state of the art satellite to space on Saturday night from the Zenit launching pad in Baikonur, Kazakhstan.

Amos 4, that was built by Israel Aerospace Industries, was launched at 11:05 p.m. Israel time. The launch is scheduled to end at the early hours of Sunday when the satellite disconnects from the final part of its launcher.

Amos 4 will take two weeks to reach its designated orbital position 67.25°E at an altitude of 36,000 kilometers.

The satellite will remain at that orbital position for several months and in orbit tests will be performed on its systems.

Following these tests the satellite will move to orbital position 65°E where it will provide a full range of satellite services for Russia, the Middle East and additional service areas.

The satellite will provide services such as Direct-to-Home, video distribution, VSAT communications and broadband internet, according to Spacecom's website.

Science and Technology Minister Ya'akov Peri, who watched the satellite's launch from a secure location in Israel, expressed pride at the launch and stressed that space and cyber are "critical issues for the security of Israel."

"The Israeli space agency is expending its activity substantially, and the launching of this satellite is another landmark in the course the state of Israel has set out on - entering the top five leading countries in the field," he said. "This is a true Israeli pride that proves to us, once more, that for Israeli technology - the sky is no longer the limit."

Amos 4 joins Spacecom's Amos 2, Amos 3 and Amos 5 satellites. Amos 6 is scheduled for a 2014 launch.
Quelle: The Jerusalem Post
The Amos 4 communications satellite, built by Israel Aerospace Industries Ltd. (IAI) (TASE: ARSP.B1) for Spacecom Satellite Communications Ltd.(TASE:SCC), was launched at 11:05 pm Saturday, Israel time. The launch used a Russian Zenit rocket from the Baikonur Cosmodrome in Kazakhstan. The launch will be completed Sunday morning, when the satellite separates from the launcher's final stage.

After the separation, the Amos 4 satellite will continue on its trajectory for two weeks to reach its designated orbital position at 67.25 degrees East at an altitude of 36,000 kilometers. The satellite will operate at this node for several months, during which in-orbit tests will be conducted. Afterwards, it will move to its orbital position at 65 degrees East where it will operate commercially.

Spacecom CEO David Pollack said, "The company congratulates IAI for the achievement in building the Amos 4. With the Amos 4, Spacecom continues its rapid expansion to new continents and large markets, becoming a regional international player for the provision of satellite communications services in the global market."

IAI CEO Joseph Weiss said, "The Amos 4 is at the forefront of technology, on a level with the world's leading satellite communications. This is an impressive achievement for IAI, which is the leader and chief contractor for all of Israel's satellite programs. The development and manufacture of the satellite by IAI's skilled and dedicated employees is an exceptional achievement for us in aerospace."

Minister of Science and Technology Yaakov Perry, who watched the launch of the Amos 4 from a secure facility in central Israel together with Israeli aerospace industry officials, said, "In the digital and satellite eras, aerospace and cyber are critical issues for Israel's security. This is a source of true pride for Israel. It once again demonstrates that for Israeli technology, the skies are no longer the limit."

Perry added, "The Israel Space Agency is greatly expanding its activity, and the launch of the satellite is another milestone on the path that Israel has embarked on - joining the five leading countries in aerospace."

Quelle; GLOBES






Zenit2-SB Start löst Meteoriten-Alarm über VLADIVOSTOK aus...

Frams: IAI-Start

Tags: satellite amos-4 launch Kazakhstan satellites ZENIT2-SB 


Sonntag, 1. September 2013 - 14:00 Uhr

Astronomie - NASA´s SDO-Mission entwirrt Prozesse innerhalb der Sonne


Observations by the Helioseismic and Magnetic Imager on NASA's Solar Dynamics Observatory show a two-level system of circulation inside the sun. Such circulation is connected to the flip of the sun's north and south magnetic poles that occurs approximately every 11 years.


Using an instrument on NASA's Solar Dynamics Observatory, called the Helioseismic and Magnetic Imager, or HMI, scientists have overturned previous notions of how the sun's writhing insides move from equator to pole and back again, a key part of understanding how the dynamo works. Modeling this system also lies at the heart of improving predictions of the intensity of the next solar cycle.

Using SDO, scientists see a performance of explosions and fountains on the solar surface. Shots of solar material leap into the air. Dark blemishes called sunspots grow, combine and disappear as they travel across the sun's face. Bright loops of charged particles – captured by magnetic fields dancing around the sun – hover in the atmosphere. This dynamic display is all powered by a complex, ever-changing magnetic current inside the sun known as the dynamo. This magnetic system flips approximately every 11 years, with magnetic north and magnetic south switching poles. This process is an integral part of the sun's progression toward a pinnacle of solar activity, known as solar maximum.

The team's recent results show that, instead of a simple cycle of flow moving toward the poles near the sun's surface and then back to the equator, the material inside the sun shows a double layer of circulation, with two such cycles on top of each other.  The results appear online in the Astrophysical Journal Letters on  Aug. 27, 2013.

"For decades people have known that the solar cycle depends on the poleward flow or material, changing the magnetic fields from one cycle to the next," said Philip Scherrer, principal investigator for HMI at Stanford University in Stanford, Calif. "We mapped out what we believed to be the flow pattern in the 1990s, but the results didn't quite make sense."

Since the mid-1990s researchers have been observing movement inside the sun using a technique called helioseismology. The technique makes use of the fact that waves course across the sun, back and forth, oscillating with an approximately five minute period. Such waves are similar to the seismic waves that spread out under the ground during an earthquake. By monitoring the oscillations seen at the surface of the sun, scientists can gather information about the material through which the waves traveled, including what the material is made of and how fast and in what direction it is moving.

Such observations quickly showed scientists how material inside the sun rotates from east to west: material moves more slowly at the poles than it does at the equator. The observations also soon showed that material moved from the equators toward the poles within the top 20,000 miles of the sun's surface – but the flow back toward the equator from the poles was not detected. Early models of all this moving material, therefore, assumed that the equator-ward flow was much lower, only occurring at the bottom of the convection layer of the sun that houses these flows, some 125,000 miles down.

"Scientists have used this assumption to describe the solar dynamo," said Junwei Zhao, a helioseismologist at Stanford University in Stanford, Calif., who is the first author on the paper. "And now we have found that it isn't right. The flow patterns we have found are sharply different."

Zhao and his colleagues observed two years worth of data from HMI, which differs from one of the best previous helioseismology instruments – the Michelson Doppler Imager on board the joint European Space Agency/NASA mission the Solar and Heliospheric Observatory, or SOHO. SOHO observed the sun in low resolution on a regular basis, but only observed it in high resolution for a couple months each year. HMI observes the sun continuously with 16 times more detail than SOHO.

Using this data, Zhao compared the helioseismology results measured at four different heights within the sun's surface, and found these results were not consistent with what the normal convention would expect. The team proposed a way to make these four sets of measurements agree with each other.

This new method not only brought the four data sets into harmony, but also helped find the long-sought equatorward flow inside the sun. The team found that the flow toward the poles does indeed occur in a layer at near the sun's surface – but the equatorward flow isn't at the bottom. Instead, the material seeps back toward the equator through the middle of the convection layer. Moreover, deep down inside the layer is a second stream of material moving toward the poles, making what the scientists refer to as a double-cell system in which two oblong flow systems are stacked on top of each other.

"This has important consequences for modeling the solar dynamo," said Zhao. "We hope our results on the sun's interior flow will provide a new opportunity to study the generation of solar magnetism and solar cycles."

Zhao and his colleagues have provided their new map of the sun's interior to scientists who simulate the dynamo. The next steps will be to see how such new models jibe with the observations seen on the sun and how it may improve our ability to understand the constant dance of magnetism on the sun.

Quelle: NASA

Tags: SDO 


Samstag, 31. August 2013 - 11:30 Uhr

Raumfahrt - Start von Ariane-V-VA215 mit EUTELSAT 25B und GSAT-7



The EUTELSAT 25B/Es’hail 1 container is rigged for its hoisting from the unloading ramp to a flatbed trailer after arrival at Félix Eboué Airport in French Guiana.  Once this action is completed, the satellite will be transferred by road to the Spaceport.
The second satellite arrives for Arianespace’s upcoming heavy-lift Ariane 5 launch
Payload preparations for Arianespace’s next Ariane 5 mission are moving into their full pace with the delivery of its second passenger – EUTELSAT 25B/ Es’hail 1 – to French Guiana, joining GSAT-7, which arrived earlier this month.
The EUTELSAT 25B/Es’hail 1 spacecraft was transported to South America aboard an Antonov An-124 cargo jetliner, which landed on July 27 at Félix Eboué Airport near the French Guiana capital city of Cayenne.  After the unloading process – aided by the giant aircraft’s tilt-up nose and its forward “kneeling” capability – the protective container with EUTELSAT 25B/Es’hail 1 was readied for transportation by road to the Spaceport, some 65 kilometers away.
Built by SSL in the U.S., this satellite will assist European telecommunications operator Eutelsat and Qatar’s Es’hailSat satellite company in responding to demand for the fastest-growing applications in the Middle East and North Africa – including video broadcasting, enterprise communications and government services.
In addition to securing Ku-band continuity for Eutelsat and additional Ku-band resources for Es’hailSat, EUTELSAT 25B/Es’hail 1 will initiate a Ka-band capability that opens business opportunities for both parties. 
The spacecraft is based on SSL’s proven 1300 satellite bus, and will provide a follow-on to the EUTELSAT 25C satellite, which currently is operated at 25.5° East.  Liftoff mass of EUTELSAT 25B/Es’hail 1 will be more than 6,000 kg.
For Arianespace’s upcoming Ariane 5 flight, targeted for August 29, EUTELSAT 25B/Es’hail 1 is to ride in the upper position of the heavy-lift launcher’s payload “stack.” 
Located below it will be the Indian GSAT-7 telecommunications satellite, which arrived in French Guiana on July 11 and has been undergoing checkout in the Spaceport’s S5 payload preparation facility. 
With an estimated liftoff mass of 2,650 kg., GSAT-7 was developed by the Indian Space Research Organisation and carries relay payloads in UHF, S-band, C-band and Ku-band. 
GSAT-7 and EUTELSAT 25B/Es’hail 1 will be lofted by Flight VA215, as designated in Arianespace’s launcher family numbering system, signifying the 215th mission with the Ariane series of launch vehicles.
It will be the fourth heavy-lift Ariane 5 mission in 2013, and follows last week’s on-target Flight VA214, which orbited Alphasat, the largest telecommunications platform ever built by Europe, along with India’s INSAT-3D meteorological platform – which uses the same basic spacecraft bus as GSAT-7.
In addition to the three Ariane 5 liftoffs performed so far this year by Arianespace at the Spaceport, the company’s other launch vehicles also have been active.  Its medium-lift Soyuz and lightweight Vega performed one launch each from French Guiana, while Arianespace’s Starsem affiliate conducted a Soyuz mission from Baikonur Cosmodrome in Kazakhstan. 
As a result, the combined flights of these three Arianespace family launchers have orbited a total of 18 payloads to date in 2013.
With the An-124 tilt nose opened and the jetliner in its “kneeling” position, the protective container with EUTELSAT 25B/Es’hail 1 is unloaded at Cayenne’s Félix Eboué Airport.
Eutelsat 25b
Quelle: arianespace
Update: 15.08.2013

EUTELSAT 25B/Es’hail 1 receives its fuel load in the Spaceport’s S5 payload preparation center as the satellite is readied for Arianespace’s upcoming dual-passenger Ariane 5 mission.


EUTELSAT 25B/Es’hail 1 is “topped off” for Arianespace’s Ariane 5 mission on August 29

August 14, 2013 – Ariane Flight VA215

Fueling is underway at the Spaceport with EUTELSAT 25B/Es’hail 1 – the largest of two satellite passengers for Arianespace’s next Ariane 5 mission, scheduled to lift off from French Guiana late this month.

The satellite is being “topped off” in the S5A fueling and integration hall of the Spaceport’s S5 payload preparation center, marking another step in this spacecraft’s pre-launch processing.

EUTELSAT 25B/Es’hail 1 was built by Space Systems/Loral (SSL) for two users: European telecommunications operator Eutelsat Communications and Qatar’s Es’hailSat Satellite Company; with the high-power, multi-mission relay platform to provide flexible coverage over the Middle East, North Africa and Central Asia. 

The satellite is designed to deliver television broadcasting, telecommunications and government services with its Ku-band payload, while Ka-band relay capability is included to open business opportunities for both Eutelsat and Es’hailSat.

Based on Space Systems/Loral’s SSL 1300 spacecraft platform, EUTELSAT 25B/Es’hail 1 is equipped with four steerable spot beam antennas and four deployable reflectors, along with advanced command and telemetry capabilities.  After deployment by Ariane 5, the satellite will be positioned at 25.5 degrees East longitude, with a designed operating lifetime of 15 years or more.

For Arianespace’s August 29 launch, EUTELSAT 25B/Es’hail 1 is to be installed in the upper position of Ariane 5’s payload “stack,” with the flight’s co-passenger – India’s GSAT-7 communications satellite from the Indian Space Research Organisation – riding below it.

The lift performance on this fourth heavy-lift Arianespace mission in 2013 will be more than 8,550 kg., which includes the 6,000-kg.-plus liftoff mass of EUTELSAT 25B/Es’hail 1 and GSAT-7’s estimated mass of 2,550 kg.

Designated Flight VA215 in Arianespace’s launcher family numbering system, the upcoming launch follows heavyweight Ariane 5 missions conducted so far this year from the Spaceport in July (Flight VA214, with Alphasat and INSAT-3D), during June (Flight VA213, orbiting the Automated Transfer Vehicle Albert Einstein), and in February (Flight VA212, with Amazonas 3 and Azerspace/Africasat-1a).

In other 2013 Arianespace launch activity, the medium-lift Soyuz was deployed in June from French Guiana with four O3b Networks satellites, and the lightweight Vega performed a Spaceport mission in May with the Proba-V, VNREDSat-1 and ESTCube-1 payloads.

Completing the company’s activity to date in 2013 was a February Soyuz flight from Kazakhstan’s Baikonur Cosmodrome, performed by Arianespace’s Starsem affiliate to loft six Globalstar second-generation satellites.

Quelle: arianespace


Update: 18.08.2013

Focus on India: GSAT-7 is mated for Arianespace’s next launch, and Indian Independence Day is celebrated at the Spaceport

The protective container with GSAT-7 is moved into Ariane 5’s Final Assembly Building, where this Indian communications satellite was mated with its heavy-lift launcher.


India was in the spotlight at the Spaceport in French Guiana this week as its GSAT-7 communications satellite was mated to the Ariane 5 for Arianespace’s August 29 launch, and mission team members gathered to celebrate the country’s Independence Day.

During activity in the Final Assembly Building for Ariane 5, GSAT-7 was installed atop the heavy-lift launcher, positioning this spacecraft as the lower passenger in the payload “stack.” 

GSAT-7 will provide relay capacity in UHF, S-band, C-band and Ku-band from an orbital position of 74 deg. East., with a liftoff mass estimated at 2,550 kg.  Developed by the Indian Space Research Organisation, it utilizes India’s standard I-2K spacecraft bus – the same as for the country’s INSAT-3D meteorological satellite orbited on Arianespace’s previous Ariane 5 mission, performed July 25.

Following GSAT-7’s integration on Ariane 5, members of the satellite team joined with Arianespace personnel to celebrate India’s Independence Day on August 15.  As part of the observance, a flag-raising ceremony was held at the Spaceport’s S5 payload preparation facility, where GSAT-7 had undergone its pre-launch checkout and fueling.

The August 29 mission with GSAT-7 will be Arianespace’s fourth Ariane 5 liftoff of 2013, and also will carry the EUTELSAT 25B/Es’hail 1 telecommunications platform in another of the heavy-lift launcher’s dual-passenger flights.
A flag-raising ceremony in front of the Spaceport’s S5 payload preparation facility was part of the Indian Independence Day celebration with GSAT-7 mission team members and Arianespace personnel.
Quelle: arianespace
Update: 23.08.2013

Build-up of the Ariane 5 payload “stack” continues for Arianespace’s August 29 mission


August 19, 2013 – Ariane Flight VA215

EUTELSAT 25B/Es’hail 1 has been installed atop the SYLDA dispenser system during integration activity at the Spaceport, positioning this satellite for its ride as the upper passenger in Ariane 5’s payload “stack” for the August 29 Arianespace heavy-lift mission.

This marks a new milestone in preparations for Flight VA215 from French Guiana, which will loft EUTELSAT 25B/Es’hail 1 and GSAT-7. 

Once in orbit, EUTELSAT 25B/Es’hail 1 will be used by two operators: the European telecommunications operator Eutelsat Communications; and Qatar’s Es’hailSat Satellite Company. 

As a high-power, multi-mission relay platform, the satellite is to deliver television broadcasting, telecommunications and government services with its Ku-band payload, while Ka-band relay capability is included to open business opportunities for both Eutelsat and Es’hailSat.  It was produced by Space Systems/Loral (SSL) with a design operating lifetime of 15 years or more, and will be positioned at 25.5 deg. East after deployment by Ariane 5.

EUTELSAT 25B/Es’hail 1 was installed on the SYLDA dispenser in the payload preparation area of the Ariane 5’s Final Assembly Building.  With this step completed, the satellite/SYLDA combination is ready for encapsulation in the payload fairing, followed by integration on Ariane 5 – positioning it atop GSAT-7, which already has been mated to the launcher.

Flight VA215 will be Arianespace’s fourth heavy-lift mission in 2013 and the 215th launch of an Ariane-series vehicle from French Guiana.

The EUTELSAT 25B/Es’hail 1 satellite is ready for its integration on SYLDA, and is installed atop the dispenser in Ariane 5’s Final Assembly Building.

Ariane 5 build-up is completed for Arianespace’s upcoming flight with EUTELSAT 25B/Es’hail 1 and GSAT-7


August 22, 2013 – Ariane Flight VA215

The heavy-lift Ariane 5 for Arianespace’s August 29 mission is now complete at the Spaceport in French Guiana following integration of its second passenger – the EUTELSAT 25B/Es’hail 1 satellite.

Encapsulated in an ogive-shaped payload fairing, EUTELSAT 25B/Es’hail 1 and the SYLDA dispenser system on which it is installed were lowered over GSAT-7 – which was mated with the Ariane 5 earlier this month – to finish launcher build-up at the Spaceport’s Final Assembly Building.

With both satellites now installed, Ariane 5 is ready for the final pre-flight preparations – including the launch readiness review on August 27, followed by its rollout to the launch zone the next day, and the subsequent countdown to a 50-minute launch window that opens at 5:30 p.m. local time in French Guiana on August 29.

Riding in the upper position of the payload “stack,” EUTELSAT 25B/Es’hail 1 will be deployed first, at approximately 27 minutes after liftoff.

Once in orbit, the spacecraft will be used by European telecommunications operator Eutelsat Communications and Qatar’s Es’hailSat Satellite Company to deliver television broadcasting, telecommunications and government services in the Ku-band range, while its Ka-band capability will open business opportunities for both operators. This high-power, multi-mission relay platform was built by Space Systems/Loral (SSL) and will be positioned at 25.5 deg. East, with a design life of 15 years or more.

Following the release of EUTELSAT 25B/Es’hail 1, GSAT-7 – the mission’s lower passenger – will be deployed at 34 minutes after liftoff, completing the delivery of this Ariane 5’s payloads into geostationary transfer orbit.

The Indian satellite, developed by the nation’s Indian Space Research Organisation (ISRO) space agency, will provide relay capacity in UHF, S-band, C-band and Ku-band from an orbital position of 74 deg. East during its design life of seven years.

Designated Ariane Flight VA215 in the company’s launcher family numbering system, this mission represents the 215th flight of an Ariane-series vehicle, as well as the fourth Ariane 5 liftoff in 2013.

The “upper composite” – with EUTELSAT 25B/Es’hail 1 and the SYLDA dispenser system encapsulated in Ariane 5’s payload fairing – was lowered over GSAT-7 during activity in the Spaceport’s launcher Final Assembly Building.

Quelle: arianespace


Update: 26.08.2013

Indian Space Research Organisation (ISRO) is gearing up for its next mission --- the launch of naval defence satellite GSAT 7 --- even as the revised launch dates for the aborted GSLV D5 mission are yet to be announced.

The GSAT 7 or INSAT 4F is primarily meant for the use of the Indian Navy and other armed forces. It will cater to their telecommunication needs.

According to ISRO, the satellite is configured to provide a wide range of spectrum ranging from low bit rate voice to high bit rate data communication. The satellite with a service life of 15 years will provide communication capabilities to users over a wide oceanic region as well as the Indian subcontinent.

The satellite will be launched by the European space company Arianespace from its launch facility in Kourou, French Guiana between 2 to 2.50 am (Indian Standard Time) on August 30. The Ariane 5 launch vehicle will also have on board the EUTELSAT 25B/E. The GSAT 7 is expected to deploy the second around 34 minutes after the liftoff.

Arianespace on Saturday said that the integration of both payloads were complete and the final pre-flight preperations were on. This will be followed by a final launch readiness review on August 27.

The ISRO also announced the turning on of payloads aboard the INSAT 3D satellite which was recently launched by Arianespace. The satellite had developed some anomalies and resulted in terse moments for the ISRO’s scientists as they coaxed it to its preset orbit. An inquiry has been ordered into the same. However, the initial products from the satellite have already started coming in, the ISRO stated.




Update: 28.08.2013


Update 29.08.2013





Update 22.15 MESZ: Frams von LIVE-Start arianespace-tv







Update: 30.08.2013 

Arianespace launch VA215 - Mission accomplished! 
Ariane 5 ECA orbits EUTELSAT 25B/Es'hail 1 and GSAT-7
On Thursday, August 29, Arianespace carried out the 57th successful Ariane 5 launch in a row, orbiting two telecommunications satellites: EUTELSAT 25B/Es’hail 1 for the Qatari and European operators, Es’hailSat and Eutelsat, and GSAT-7 for the Indian Space Research Organisation (ISRO).
Fourth Ariane 5 launch in 2013, 57th success in a row: Arianespace continues to offer the world's most reliable launch service!
Today's successful mission, the 57th in a row for the European launcher, once again proves the reliability and availability of the Ariane 5 launch system. It also confirms that Arianespace continues to set the standard for guaranteed access to space for all operators, including national and international space agencies, private industry and governments.
Following the announcement of the orbital injection of the EUTELSAT 25B/Es'hail 1 and GSAT-7 satellites, Arianespace Chairman and CEO Stéphane Israël said: "The 57th successful launch in a row of Ariane 5, the 80th for our family of the Ariane 5, Soyuz and Vega launchers, once again confirms the unrivaled reliability of our launch systems. I would like to thank Astrium, as the industrial prime contractor for Ariane 5, along with all other manufacturers involved, and the CNES teams at the Guiana Space Center, for working with us to make this achievement possible. On behalf of everybody at Arianespace, I would like to express our pride this evening in rising to the challenge of meeting the requirements of our three customers, Es'hailSat, Eutelsat and ISRO. Es'hailSat, like 80% of all new players in the telecommunications satellite market, chose Arianespace to orbit their first satellite. I realize that this is a particularly important moment for Es'hailSat, and for its CEO, Ali Ahmed al-Kuwari. Eutelsat and ISRO are both long-standing partners to Arianespace, reaching back over 30 years, and they continue to entrust us with their satellites year after year, within the scope of partnerships that truly honor us. I would like to express my sincere thanks to both of these companies; this latest successful launch shows that they made the right choice by selecting Arianespace! I would also like to personally thank Michel de Rosen, CEO of Eutelsat, and S.K. Shivakumas, Director of the ISRO Satellite Centre, for sharing this launch with us. And last but not least, I would like to thank Nicole Bricq, French Minister of Foreign Trade, and Her Excellency Dr. Hessa Al-Jaber, Qatari Minister for Information and Communication Technology, for kindly agreeing to join us this evening in the Jupiter control room at the Guiana Space Center."
Quelle: arianespace
Update: 31.08.2013

Confirmed: EUTELSAT 25B/Es’hail 1 and GSAT-7 are on their way to final orbits following Arianespace’s accurate Ariane 5 launch


 Ariane Flight VA215

The two passengers carried on Arianespace’s August 29 success with Ariane 5 – EUTELSAT 25B/Es’hail 1 and GSAT-7 – were placed into a highly accurate geostationary transfer orbit by the heavy-lift launcher, preparing these spacecraft for their useful operational lifetimes.

Ariane 5’s accuracy once again was underscored during the mission, which is designated Flight VA215 in Arianespace’s numbering system. Estimated orbital parameters at the injection of its cryogenic upper stage were:
- Perigee: 249.3 km. for a target of 249.3 km.
- Apogee: 35,942 km. for a target of 35,924 km.
- Inclination: 3.48 deg. for a target of 3.50 deg.

Further confirmation of the on-target deliveries by Ariane 5 came from Arianespace’s customers. India’s national Indian Space Research Organisation space agency, which developed GSAT-7, today announced that Ariane 5 precisely placed the communications satellite into its intended geostationary transfer orbit.

In addition, ISRO stated that GSAT-7’s solar panels have been successfully deployed and are generating power, and that initial checks indicated normal health.  During the next steps, GSAT-7’s liquid apogee motor will raise the satellite to geostationary orbit by September 4 with three orbit raising maneuvers.

GSAT-7 ultimately will be positioned at an orbital slot of 74 deg. East, from which it will provide India with UHF, S-band, C-band and Ku-band relay capacity over the country’s land mass.

In another statement issued today, Eutelsat Communications and Es’hailSat confirmed their jointly-owned EUTELSAT 25B/Es’hail 1 high-power relay platform also was on course for geostationary orbit.

The spacecraft’s solar panels were deployed within four hours of separation with Ariane 5, and preparations rapidly commenced for the first of four apogee motor firings to raise EUTELSAT 25B/Es’hail 1 to its intended orbital position – 25.5 deg. East – for a planned service entry at the end of October.

Once in its final orbital slot, EUTELSAT 25B/Es’hail 1 – which was built by Space Systems/Loral (SSL) – will deliver Ku-band television broadcasting, telecommunications and government services for the Middle East, North Africa and Central Asia; while the satellite’s Ka-band capability will open business opportunities in these regions for both of its operators.

Yesterday’s launch marked the 57th consecutive success for Arianespace’s Ariane 5, as well as the workhorse vehicle’s fourth flight conducted so far during 2013 – delivering seven spacecraft with a combined total payload lift performance of more than 50,000 kg. 

The mission’s launcher was the 14th Ariane 5 ECA version delivered to Arianespace as part of the PB production batch from Astrium Space Transportation – the industrial prime contractor and integrator. The PB production contract was signed in 2009 to ensure the continuity of Arianespace’s launch services and consists of 35 Ariane 5 ECA launchers – covering the timeframe from 2010 to 2016. It follows the PA production batch, which involved 30 Ariane 5s.
Quelle: arianespace



Tags: Ariane 5 launch EUTELSAT 25B/Es’hail 1 Launch of EUTELSAT 25B Launch GSAT-7 Ariane Flight VA215 


Samstag, 31. August 2013 - 11:00 Uhr

Luftfahrt - Kleinflugzeuge (UAVs) erstellen aktuelle Luftbilder


Das Deutsche Unternehmen MAVinci, Alumni des ESA Gründerzentrums in Darmstadt, bietet jetzt eine schnelle und einfache Methode zur Landvermessung mithilfe unbemannter Kleinflugzeuge an.


Die automatischen Kleinflugzeuge (UAVs) des Unternehmens erstellen aktuelle Luftbilder, die früher nur von bemannten Flugzeugen erstellt werden konnten. Die UAVs werden mittels Satellitennavigationdaten vom Autopilot gesteuert und fliegen nach vorher festgelegten Routen. Sie haben nur eine Flügelspannweite von 1.6 m und weniger als 3 kg Abfluggewicht.  

“Unsere UAVs sind kosteneffizient, kurzfristig verfügbar und einfach zu handhaben, um Entwicklungsgebiete, Baustellen, Minen, Katastrophengebiete, Mülldeponien, zu überwachen, um nur ein paar zu nennen“, sagt Johanna Claussen, Geschäftsführerin von MAVinci. “Sie können Kameras für den sichtbaren Bereich oder andere kundenspezifische Messgeräte tragen.”

Die MAVinci Unternehmer haben ihr Kleinflugzeuge mit Unterstützung des ESA-Gründerzentrums entwickelt und haben ihre Idee in eine erfolgreiche Firma umgewandelt.  

ESA-Ingenieure unterstützten MAVinci bei der Nutzung von Satellitennavigationsdaten, das optische Labor des Technologiezentrums ESA / ESTEC in den Niederlanden half bei der Kalibrierung der Kamera.

Vor dem Abflug wird der Flugplan entworfen und zum Flugzeug hochgeladen. Vom Start bis zur Landung ist der Flug vom Autopilot-gesteuert. Das UAV wird aber per Funk von einem Sicherheitspiloten vor Ort beobachtet, der jederzeit die Kontrolle übernehmen kann.

Noch während der Inkubationszeit im ESA-Zentrum im Jahr 2009 wurde das Unternehmen beauftragt, in Spanien Landvermessungen durchzuführen. Die Erosion ist in weiten Gebieten Südeuropas und Nordafrikas ein ernsthaftes Problem für die Landnutzung und Wasserversorgung.

Eines von MAVincis Kleinflugzeugen hat mehrere erodierte Schluchten in Andalusien beflogen, mit dem Ziel, die Dynamik der Erosion besser zu verstehen und ortsansässigen Bauern zu helfen.

“Der Markt für Landvermessung mit UAVs wächst sehr schnell, besonders dieses Jahr. Mit Distributoren in 12 Ländern können wir nicht einmal so viele Systeme produzieren wie unsere Kunden kaufen möchten“, erläutert Johanna Claussen.

Mit seinen Technologietransferprogrammen (TTP) hat die ESA acht Gründerzentren in sechs Ländern, die Jungunternehmen und Existenzgründern helfen, ihre Ideen zu verwirklichen und Raumfahrttechnik und raumfahrtgestütze Dienste zu nutzen, um Europäische Unternehmen zu gründen.

Mehr als 200 neue Firmen wurden bereits gestartet und weitere 75 werden jedes Jahr in den Zentren unterstützt.

Quelle: ESA

Tags: UAVs 


Samstag, 31. August 2013 - 10:45 Uhr

Astronomie - Kosmische Raupe


Cosmic caterpillar

This light-year-long knot of interstellar gas and dust resembles a caterpillar on its way to a feast. But the meat of the story is not only what this cosmic caterpillar eats for lunch, but also what's eating it. Harsh winds from extremely bright stars located 15 light-years away from the knot towards the right edge of the image, are blasting ultraviolet radiation at this "wanna-be" star and sculpting the gas and dust into its long shape.

The caterpillar-shaped knot, called IRAS 20324+4057, is a protostar in a very early evolutionary stage. It is still in the process of collecting material from an envelope of gas surrounding it.

This image is a composite of Hubble Advanced Camera for Surveys (ACS) data taken in green and infrared light in 2006, and ground-based hydrogen data from the Isaac Newton Telescope in 2003, as part of the IPHAS H-alpha survey. The object lies 4500 light-years away in the constellation of Cygnus (The Swan).

Credits: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and IPHAS

Tags: Cosmic caterpillar Hubble 


Freitag, 30. August 2013 - 23:00 Uhr

Astronomie - Feuerkugel heller als der Vollmond über Südosten der USA


MAJOR FIREBALL EVENT, UPGRADED: NASA's Meteoroid Environment Office has upgraded its estimates of a major fireball that exploded over the southeastern USA around 2:30 AM on August 28th. Lead researcher Bill Cooke says "the fireball reached a peak magnitude of -13, brighter than a Full Moon, and cast shadows on the ground. This indicates that the meteoroid had a mass of over 50 kg (110 lbs) and was about 40 cm (16 inches) in diameter. It hit the top of Earth's atmosphere traveling 23.7 km/s (53,000 mph)." Watch the movie, then read more about the fireball below:



Feuerkugel überstrahlt selbst den Vollmond...

"As far as I know, this is the brightest event our network has observed in 5 years of operation," he continues. "There are reports of sonic booms reaching the ground, and data from 4 doppler radars indicate that some meteorites may have fallen along the fireball's ground track." (Note: The city in the ground track map is Cleveland, Tennessee, not Cleveland, Ohio.)

Using data from multiple cameras, Cooke has calculated a preliminary orbit for the meteoroid. The shape and dimensions of the orbit are similar those of a Jupiter-family comet. If meteorites are recovered from the Tennessee countryside, their chemical composition will tell researchers more about the origin of the fireball.

Quelle: NASA

Tags: Fireball Feuerkugel 


Freitag, 30. August 2013 - 22:30 Uhr

Raumfahrt - TerraSAR-X -Weitwinkel aus dem Weltall



Aufnahme der Deutschen Bucht im WideScan-Modus

TerraSAR-X-Aufnahme von Sylt

Windparks im Radarbild

Gletscher und Eisberge der Antarktis


Ganz offiziell könnte der deutsche Radarsatellit TerraSAR-X schon seit über einem halben Jahr außer Dienst sein - solange hat er bereits seine vorgesehene Lebensdauer hinter sich gelassen. Doch die Ingenieure des Deutschen Zentrums für Luft- und Raumfahrt (DLR) haben dem Satelliten, der am 15. Juni 2007 ins All startete, sogar noch einen neuen Modus beigebracht: Nun kann TerraSAR-X Bildstreifen mit einer Breite von über 200 Kilometern aufnehmen. "Dazu tastet der Satellit dieses große Gebiet durch vielfaches, enorm schnelles Schwenken des Radarstrahls quer zur Flugrichtung in mehreren Schritten ab", erläutert DLR-Missionsmanager Stefan Buckreuß. Die Aufnahme der Deutschen Bucht beispielsweise zeigt die friesischen Inseln von Borkum bis Wangerooge und unter anderem die Städte Wilhelmshaven und Bremen. Der neue "Weitwinkel"-Modus ist vor allem für Meeresforscher spannend, die damit Tidenhub, Veränderungen im Wattenmeer, Schiffsbewegungen, Wellenmuster, Eisbewegungen oder auch Windaufkommen untersuchen können.

Über 120 000 Bilder hat der Radarsatellit TerraSAR-X seit seinem Start bereits geliefert. Bisher waren die Bildstreifen des TerraSAR-X-Satelliten aber auf eine Breite von 100 Kilometern beschränkt. "Zum ersten Mal haben wir nun eine Aufnahme der kompletten Deutschen Bucht von Osten nach Westen zu einem Zeitpunkt und in hoher Auflösung", betont Dr. Susanne Lehner. Das freifallende Watt und seine Priele zwischen den einzelnen Inseln und der Küste, der hohe Wasserstand in der Elbmündung und bei Sylt - für die Ozeanographin bietet die Radaraufnahme aus über 500 Kilometern Höhe zahlreiche Informationen. Weiter nördlich schaut der Satellit auf Sylt und mehrere Windparks mit Windkrafträdern, die sich als geometrisch angeordnete helle Punkte auf der Schwarz-Weiß-Aufnahme zeigen. Auch einzelne Schiffe sind auf den Radaraufnahmen erkennbar, so dass mit einer Auflösung von 40 Metern im sogenannten Wide-ScanSAR-Mode auch die Schiffsrouten verfolgt werden können. Eines sieht man auf den ersten Testaufnahmen zum Glück allerdings nicht - "Wir können keine Ölverschmutzung in der Deutschen Bucht feststellen - diese würden sich auf der Aufnahme deutlich abzeichnen, wenn sie vorhanden wären", erläutert DLR-Wissenschaftlerin Susanne Lehner. Bei  Plattformen in der nördlichen Nordsee hingegen stießen die Wissenschaftler bei der Auswertung weiterer Satellitenbilder bereits auf Ölverschmutzungen.

Verlängerung der TerraSAR-X-Mission

DLR-Wissenschaftlerin Dana Floricioiu  nutzt die Aufnahmen, um beispielsweise das Kalben von Eisbergen oder die Bewegung der Gletscher zu untersuchen. "Der neue Modus ermöglicht es, weiträumig glaziologische Prozesse zu beobachten und Eisstrukturen zu kartieren." Mit Aufnahmen in Zeitabfolgen beobachtet die Wissenschaftlerin auch die Risse, die im Eis entstehen, bevor ein Eisberg sich von der Eismasse löst. In der Pine Island Bay in der Antarktis hat Floricioiu den Eisberg B22A im Blick, der mit seinen 81,5 mal 44,4 Kilometern ein Überbleibsel eines noch größeren Eisbergs aus dem Jahr 2002 ist.

"Mit dem neuen Modus haben die Wissenschaftler auf einen Schlag einen sehr guten Überblick über ein großes Gebiet", betont Missionsmanager Stefan Buckreuß.  Für die Ingenieure und Wissenschaftler ist diese neue Aufnahmetechnik, die ursprünglich für die Mission gar nicht vorgesehen war, ein Beleg dafür, dass der Satellit im All noch nicht in Rente gehen wird: "Der technische Zustand von TerraSAR-X ist sehr gut, und die Treibstoffreserven erlauben noch einen Betrieb bis mindestens 2015."

Über die Mission

TerraSAR-X wird im Auftrag des Deutschen Zentrums für Luft- und Raumfahrt (DLR) mit Mitteln des Bundesministeriums für Wirtschaft und Technologie realisiert. Es ist der erste deutsche Satellit, der im Rahmen einer so genannten Public Private Partnership (PPP) zwischen dem DLR und Astrium realisiert wird: Die Nutzung von TerraSAR-X-Daten für wissenschaftliche Zwecke liegt in der Zuständigkeit des DLR, das auch die Konzeption und Durchführung der Mission sowie die Satellitensteuerung übernimmt. Astrium beteiligt sich an den Kosten für Entwicklung, Bau und Einsatz des Satelliten. Die Infoterra GmbH, eine eigens zu diesem Zweck gegründete Tochtergesellschaft von Astrium, übernimmt die kommerzielle Vermarktung der Daten.


Quelle: DLR

Tags: TerraSAR-X 


Freitag, 30. August 2013 - 21:26 Uhr

Raumfahrt - Entwicklung von Nanosat Micro Raketenantriebe


L. Brad King's prototype of a ferrofluid ion thruster. When subjected to voltage, the points of the crown arise from a ring-shaped trench circling a one-inch block of aluminum. L. Brad King image


Nanosatellites are smartphone-sized spacecraft that can perform simple, yet valuable, space missions. Dozens of these little vehicles are now tirelessly orbiting the earth performing valuable functions for NASA, the Department of Defense and even private companies.

Nanosatellites borrow many of their components from terrestrial gadgets: miniaturized cameras, wireless radios and GPS receivers that have been perfected for hand-held devices are also perfect for spacecraft. However, according to Michigan Technological University’s L. Brad King, there is at least one technology need that is unique to space: “Even the best smartphones don’t have miniaturized rocket engines, so we need to develop them from scratch.”

Miniature rockets aren’t needed to launch a nanosatellite from Earth. The small vehicles can hitchhike with a regular rocket that is going that way anyway. But because they are hitchhikers, these nanosats don’t always get dropped off in their preferred location. Once in space, a nanosatellite might need some type of propulsion to move it from its drop-off point into its desired orbit.  This is where the micro rocket engine comes in.  

For the last few years, researchers around the world have been trying to build such rockets using microscopic hollow needles to electrically spray thin jets of fluid, which push the spacecraft in the opposite direction. The fluid propellant is a special chemical known as an ionic liquid. A single thruster needle is finer than a human hair, less than one millimeter long and produces a thrust force equivalent to the weight of a few grains of sand. A few hundred of these needles fit in a postage-stamp-size package and produce enough thrust to maneuver a nanosatellite.

These new electrospray thrusters face some design challenges, however. “Because they are so small and intricate, they are expensive to make, and the needles are fragile,” says King, the Ron and Elaine Starr Professor of Mechanical Engineering-Engineering Mechanics. “They are easily destroyed either by a careless bump or an electrical arc when they’re running.”

To get around the problem, King and his team have developed an elegant strategy: eliminate the expensive and tedious microfabrication required to make the needles by letting Mother Nature take care of the assembly. “We’re working with a unique type of liquid called a ferrofluid that naturally forms a stationary pattern of sharp tips in the liquid surface,” he says. “Each tip in this self-assembling structure can spray a jet of fluid just like a micro-needle, so we don’t actually have to make any needles.”

Ferrofluids have been around since the 1960s. They are made of tiny magnetic particles suspended in a solvent that moves when magnetic force is applied. King illustrates with a tiny container holding a ferrofluid made of kerosene and iron dust. The fluid lies flat until he puts a magnet beneath it. Then suddenly, the liquid forms a regular series of peaks reminiscent of a mountain range or Bart Simpson’s haircut.  These peaks remain perfectly stable despite vigorous shaking and even turning the container upside down. It is, nonetheless, completely liquid, as a finger-tip touch proves undeniably. When the magnet is removed, the liquid relaxes to a perfectly flat surface.

King’s team was trying to make an ionic liquid that behaved like a ferrofluid when they learned about a research team at the University of Sydney that was already making these substances. The Sydney team was using magnetic nanoparticles made by the life-sciences company Sirtex, which are used to treat liver cancer. “They sent us a sample, and we’ve used it to develop a thruster,” King said. “Now we have a nice collaboration going. It’s amazing that the same technology used to treat cancer can also function as a micro rocket for spacecraft.”

King’s first thruster is made of a one-inch block of aluminum containing a small ring of the special fluid. When a magnet is placed beneath the block, the liquid forms a tiny, five-tipped crown. When an electric force is then applied to the ferrofluid crown liquid jets emerge from each point, producing thrust.  “It’s fascinating to watch,” King says. “The peaks get taller and skinnier, and taller and skinnier, and at some point the rounded tips instantly pop into nano-sharp points and start emitting ions.”

The thruster appears to be almost immune to permanent damage. The tips automatically heal themselves and re-grow if they are somehow damaged. King’s team has already demonstrated its self-healing properties, albeit inadvertently. “We accidentally turned the voltage up too high, and the tips exploded in a small arc,” King says. While this would spell death for a typical thruster, “A completely new crown immediately formed from the remaining ferrofluid and once again resumed thrusting.”

Their thruster isn’t ready to push a satellite around in orbit just yet. “First we have to really understand what is happening on a microscopic level, and then develop a larger prototype based on what we learn,” King said. “We’re not quite there yet; we can’t build a person out of liquid, like the notorious villain from the Terminator movies. But we’re pretty sure we can build a rocket engine.”

King has applied for a patent on the new technology. The research is funded by the Air Force Office of Scientific Research.

Quelle: Michigan Tech News

Tags: Nanosat Micro Rockets 


Freitag, 30. August 2013 - 21:00 Uhr

Raumfahrt-Politik - Kehrt der Kalte Krieg im Weltraum zurück?


While trouble brews with Moscow over Snowden and Syria, a curious aspect of domestic space policy threatens to undermine America's tough stance and makes supporting American entrepreneurship in space a national security priority. On Tuesday, Russian media reported that Moscow is "reconsidering the role of Russia's space industry in the American space exploration program." This is no idle threat. Russian cooperation is a very critical factor in America's space operations.

Firstly, a Russian state-dominated firm, NPO Energomash, produces the RD-180 engines for America's Atlas V rocket. The Atlas V, operated by United Launch Alliance, a Boeing-Lockheed Martin joint venture, is the workhorse launch vehicle for NASA robotic missions and for U.S. military satellites. It is the only U.S. vehicle rated for the launch of nuclear powered spacecraft and has been a promising option for future U.S. manned spaceflights.

Secondly, America's National Space Agency has been paying the Russian Federal Space Agency (Roscosmos) to ferry American astronauts to and from the International Space Station in its Soyuz capsules for years. With the demise of the space shuttle program, NASA has become dependent on Roscosmos and has made a further $424 million commitment to the Russians This ill-considered agreement extends our dependence on Putin's kleptocracy until at least 2017.

Seeing America in such shabby circumstances should serve to remind both liberal and conservative free-trade advocates that there are strategic national capabilities that must never be outsourced to potential adversaries, even for the sake of capturing global market efficiencies. America needs a viable, multivendor commercial space launch industry with a diversified domestic supply chain and we need it now.

This ongoing affront to our national honor is developing into a clear and present threat to our national security. Sadly, the cause of this problem is not a technical one; America has the technology to best the Russians or anyone in space. This problem has been created by old-fashioned, pork barrel politics.

Following the recommendations of the Augustine Commission the White House wisely supported NASA's Commercial Crew Integrated Capability (CCiCap formerly CCDev) program. CCiCap is the current version of the competitive, "funded Space Act Agreements." These agreements are designed to spur "New Space" firms, like Elon Musk's Space Exploration Technologies (SpaceX), with payments tied to capability demonstrations. They've been hugely successful in restoring America's ability to resupply the International Space Station with cargo. Both SpaceX and Orbital Sciences Corporation have demonstrated private orbital launch systems. California based SpaceX now has a regular manifest of deliveries to and from the station.

Oddly, while the White House has been a strong advocate for privatization in space, some Republican Senators and Members of Congress still envision America's future in space as looking more like the Postal Service or Amtrak. They've subverted CCiCap and its predecessors by diverting funding to an old school, nationalized space program known as the Space Launch System (SLS), designed to eventually carry astronauts to Mars or the asteroids. This giant launch vehicle is not well suited for primary the job at hand - delivering Americans to the ISS and satellites to Low Earth Orbit. More recently the Capitol Hill opponents of New Space have moved to force these entrepreneurial firms into the same Federal Acquisition Regulations (FAR) model that has corrupted big government aerospace projects for years. All of this delays America's return to space in a blatant effort to protect socialized space jobs in Alabama and Texas.

Despite the ironic protestation of those who advocate continuation of government run space access, CCiCap is not "corporate welfare for Elon Musk." This funded Space Act Agreement is simply the latest incarnation of a successful string of federal initiatives that have established American national competitive advantage in strategic infrastructure over the last two centuries. The transcontinental railroad, the national air traffic control system, the national highway system and the Internet were all made possible by enlightened industrial policy. Such policies take into account what the private sector does well and what the appropriate role of government is in accelerating our national capabilities. Supporting the establishment of a competitive, commercial industry is always a better investment than building another government-operated boondoggle.

To make matters worse, New Space firms are required to demonstrate capabilities far beyond those of their competitors or predecessors. For instance, under the requirements of the Human Certification Plan Review, SpaceX must prove its ability to use a Launch Escape System (LES) to safely separate the Dragon Capsule from the launch vehicle while inflight at "Max Q", the point at which the atmospheric stresses on the craft are at a peak. While Soyuz has survived a pad abort and a higher altitude abort, the Space Shuttle flew 135 operational missions without ever conducting a real test of that vehicle's dubious abort plan, unless you count the failure of the Challenger disaster. However, you can be sure that if next year's SpaceX abort test is in anyway less than perfect, the forces of socialized space will divert even more CCiCap money into their untested nationalized solution.

If this were 1960s America, we would not be held hostage to the Russian threats. We'd bolt some seats into a SpaceX dragon capsule -- something SpaceX has done -- and show them our space program is not a bargaining chip. Tuning down our risk aversion and fully funding CCiCap is the very least that Congress and NASA should do.

Greg Autry is as an Adjunct Professor of Entrepreneurship with The Lloyd Greif Center for Entrepreneurial Studies at the Marshall School of Business at the University of Southern California. He serves as Senior Economist with the American Jobs Alliance and the Coalition for a Prosperous America. His research context is New Space and he is currently researching "National Competitive Advantage in Manned Orbital Spaceflight" for the FAA Office of Commercial Space Transport as a consultant for the Futron Corporation.



Freitag, 30. August 2013 - 20:25 Uhr

Astronomie - NASA'S Chandra beobachtet Black Hole Sagittarius A


Sagittarius A*: NASA'S Chandra Catches Our Galaxy's Giant Black Hole Rejecting Food


    • New Chandra results help explain why gas near the Milky Way's supermassive black hole is so faint in X-rays.

    • Less than 1% of the material in the black hole's gravitational grasp appears to actually reach the event horizon.

  • To obtain these results, Chandra performed one of its longest observing campaigns ever - equivalent to over 5 weeks of observing time.


The center of the Milky Way galaxy, with the supermassive black hole Sagittarius A* (Sgr A*) located in the middle, is revealed in these images. As described in our press release, astronomers have used NASA's Chandra X-ray Observatory to take a major step in understanding why gas around Sgr A* is extraordinarily faint in X-rays.

The large image contains X-rays from Chandra in blue and infrared emission from the Hubble Space Telescope in red and yellow. The inset shows a close-up view of Sgr A* only in X-rays, covering a region half a light year wide. The diffuse X-ray emission is from hot gas captured by the black hole and being pulled inwards. This hot gas originates from winds produced by a disk-shaped distribution of young massive stars observed in infrared observations (mouse over the image for the distribution of these massive stars).

These new findings are the result of one of the biggest observing campaigns ever performed by Chandra. During 2012, Chandra collected about five weeks worth of observations to capture unprecedented X-ray images and energy signatures of multi-million degree gas swirling around Sgr A*, a black hole with about 4 million times the mass of the Sun. At just 26,000 light years from Earth, Sgr A* is one of very few black holes in the Universe where we can actually witness the flow of matter nearby.

Illustration of Sagittarius A


The authors infer that less than 1% of the material initially within the black hole's gravitational influence reaches the event horizon, or point of no return, because much of it is ejected. Consequently, the X-ray emission from material near Sgr A* is remarkably faint, like that of most of the giant black holes in galaxies in the nearby Universe.

The captured material needs to lose heat and angular momentum before being able to plunge into the black hole. The ejection of matter allows this loss to occur.

This work should impact efforts using radio telescopes to observe and understand the "shadow" cast by the event horizon of Sgr A* against the background of surrounding, glowing matter. It will also be useful for understanding the impact that orbiting stars and gas clouds might make with the matter flowing towards and away from the black hole.

The paper is available online and is published in the journal Science. The first author is Q.Daniel Wang from University of Massachusetts at Amherst, MA; the co-authors are Michael Nowak from Massachusetts Institute of Technology (MIT) in Cambridge, MA; Sera Markoff from University of Amsterdam in The Netherlands, Fred Baganoff from MIT; Sergei Nayakshin from University of Leicester in the UK; Feng Yuan from Shanghai Astronomical Observatory in China; Jorge Cuadra from Pontificia Universidad de Catolica de Chile in Chile; John Davis from MIT; Jason Dexter from University of California, Berkeley, CA; Andrew Fabian from University of Cambridge in the UK; Nicolas Grosso from Universite de Strasbourg in France; Daryl Haggard from Northwestern University in Evanston, IL; John Houck from MIT; Li Ji from Purple Mountain Observatory in Nanjing, China; Zhiyuan Li from Nanjing University in China; Joseph Neilsen from Boston University in Boston, MA; Delphine Porquet from Universite de Strasbourg in France; Frank Ripple from University of Massachusetts at Amherst, MA and Roman Shcherbakov from University of Maryland, in College Park, MD.

X-ray Image of Sagittarius A

Quelle: NASA

Tags: Sagittarius A 


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