A few days before re-entering Earth's atmosphere, the German X-ray research satellite ROSAT was targeted by the Tracking and Imaging RAdar (TIRA) at the Fraunhofer Institute for High Frequency Physics and Radar Techniques in Wachtberg, near Bonn, which is unique in Europe. TIRA is part of a global network of monitoring stations that collected data about ROSAT. From this data, the orbit was determined and images were produced. This example, acquired on 20 October 2011, clearly shows the antenna mast of the satellite. Credit: Fraunhofer FHR.
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The German Aerospace Center (DLR) has identified the ROSAT’s satellite final resting place as the Bay of Bengal, off South Asia. The minivan-sized satellite re-entered the atmosphere at 0150 GMT on Sunday, October 23, 2011 (9:50 p.m. EDT on Oct. 22) and any pieces of the 21-year old satellite that survived the fiery trip likely crashed into the water. However, the ROSAT_Re-entry Twitter feed reports there is still some ambiguity, and re-entry likely took place sometime between 01:50 and 01:51, with error bar of plus or minus 7 minutes. That could make a huge difference in where debris landed. (Updated with new map, below.)
No sightings of any debris have been reported. Most of ROSAT’s parts were expected to burn up in the atmosphere, but up to 30 fragments weighing a total of 1.87 tons (1.7 metric tons) may have crashed.
Map posted by ROSAT_Reentry Twitter feed, which indicated locations on re-entry path, +/- 7 mins. Still ambiguity between 01:50 and 01:51 locations
The Bay of Bengal is located between India and Myanmar.
Yesterday, some estimations put the satellite as possibly re-entering over Northern Thailand, but again, no debris was reported. DLR now says the more precise determination of the time and location of re-entry was based on the evaluation of data provided by international partners, including the USA’s Space Command.
“With the re-entry of ROSAT, one of the most successful German scientific space missions has been brought to its ultimate conclusion. The dedication of all those involved at DLR and our national and international partners was exemplary; they are all deserving of my sincere thank you,” said Johann-Dietrich Wörner, Chairman of the Deutsches Zentrum für Luft- und Raumfahrt (DLR) Executive Board.
Artist's Concept of Phoenix Mission - Credit: DARPA
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It’s the dead zone. Approximately 22,000 miles above the Earth, $300 million worth of retired satellites are simply taking up space in geosynchronous orbit. Like anything a bit elderly, they might have problems, but they’re far from useless. There are a hundred willing volunteers waiting to be retrofitted, and all they need is the wave of a magic wand to come back to life. The DARPA Phoenix program might just be the answer.
Communication satellites in geosynchronous orbit (GEO) enable vital interchanges between warfighters. When one fails, it means an expensive replacement. But what remains isn’t a burned-out shell – it’s still a viable piece of equipment which often contains still usable antennae, solar arrays and other components. The only problem is that we haven’t figured out a way to recycle them. Now DARPA’s Phoenix program is offering an answer by developing the technology necessary to “harvest” these non-working satellites and their working parts. “If this program is successful, space debris becomes space resource,” said DARPA Director, Regina E. Dugan.
However, as easy as the idea might sound, it’s going to take a lot of cooperation from a variety of applied sciences. For example, incorporating the robotics which allows a doctor to perform telesurgery from a remote location to the advanced remote imaging systems used for offshore drilling which views the ocean floor thousands of feet underwater. If this technology could be re-engineered to work at zero gravity, high-vacuum and under an intense radiation environment, it’s entirely possible to re-purpose retired GEO satellites.
“Satellites in GEO are not designed to be disassembled or repaired, so it’s not a matter of simply removing some nuts and bolts,” said David Barnhart, DARPA program manager. “This requires new remote imaging and robotics technology and special tools to grip, cut, and modify complex systems, since existing joints are usually molded or welded. Another challenge is developing new remote operating procedures to hold two parts together so a third robotic ‘hand’ can join them with a third part, such as a fastener, all in zero gravity. For a person operating such robotics, the complexity is similar to trying to assemble via remote control multiple Legos at the same time while looking through a telescope.”
Now enter DARPA’s System F6 – the master satellite. It will host affordable, smaller scale electronics and structural models that provide on-board control. These smaller units will be able to communicate with each other and the master satellite – working together to harness the potential of the retired satellite’s assets. Right now, the Phoenix program is looking for the automation technology for creating a new breed of “satlets,” or nanosatellites. These can be sent into space much more economically through existing commercial satellite launches and then robotically attached to the elderly satellites to create new systems.
Artist Concept of System F6 - Credit: DARPA
System F6 (Future, Fast, Flexible, Fractionated, Free-Flying Spacecraft United by Information Exchange) will be fascinating in itself… a hive of wirelessly-interconnected modules capable of communicating with each other – sharing resources among themselves and utilizing resources found elsewhere within the cluster. “The program is predicated on the development of open interface standards—from the physical wireless link layer through the network protocol stack, including the real-time resource sharing middleware and cluster flight logic—to enable the emergence of a space “global commons” which would enhance the mutual security posture of all participants through interdependence.” says the DARPA team. “A key program goal is the industry-wide promulgation of these open interface standards for the sustainment and development of future fractionated systems.”
Right now the Phoenix program is looking for high tech expertise needed to develop a payload orbital delivery system. The PODS units will be needed to safely house the satlets during launch. The next step is an independent servicing station which will be placed in GEO and connected to PODS. The service module will be home to equipment such as mechanical arms and remote vision systems… the virtual “operating” center to make the DARPA Phoenix program a success.
Initial reports said ROSAT fell sometime during this track. Credit: DLR and ROSAT_Reentry Twitter.
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It’s official: the ROSAT satellite has come down. The Deutsches Zentrum für Luft- und Raumfahrt (DLR), the German Space Agency confirmed the satellite plunged to Earth sometime between 1:45 UTC and 2:15 UTC on Oct. 23, 2011 (between 8:45 and 9:15 EDT Oct. 22) There is currently no confirmation if pieces of debris have reached Earth’s surface.
Update: US Strategic Command estimates an entry time of 1:50 UTC +/- 7 Minutes. This entry time would put the satellite in the Indian Ocean, and not over China as reported below. The DLR said that after further analysis they should be able to provide more information about exactly where the debris hit.
The @ROSAT_Reentry Twitter feed posted the picture above, indicating the satellite’s fall occurred sometime during the groundtrack shown.
Other reports via Twitter from skywatchers around the world had no sightings of any lit debris falling, or any actual sightings of the satellite passing overhead since 23:30 UTC on Oct. 22. Some news reports say it could have re-entered over China, but it likely didn’t make it as far as Korea or Japan.
We’ll provide more information when it becomes available.
This latest video rendering from from Analytical Graphics, Inc. (AGI) shows ROSAT’s current orbit, the satellite’s ground track, and the estimated model of the break-up and debris scattering. Deutsches Zentrum für Luft- und Raumfahrt (DLR), the German Space Agency has now refined the re-entry to sometime between October 22 and 23, 2011, plus or minus one day. DLR says this slot of uncertainty will be reduced as the date of re-entry approaches. However, even one day before re-entry, the estimate will only be accurate to within plus/minus five hours.
The orbit extends from 53 degrees northern and southern latitude, and all areas in that region could be affected by its re-entry. The bulk of the debris will impact near the ground track of the satellite, but larger parts of the satellite, including its 32 inch, 400 kg mirror, could fall to Earth in a 80-kilometer-wide path along the track.
Update: A report from the ROSAT_Renetry Twitter feed posted at 18:00 UT on October 20 said they expect re-entry in 64 hours. “ROSAT orbit 88.58 minutes 196.8 x 201.7 km, Position 26.6S,164.0W alt=203.2km Lit ~Re-entry 64 hours”
We’ll provide more updates as they become available. You can check the DLR ROSAT webpage for more updates.
Compare the view of the ROSAT satellite, as seen from Earth on September 23 and October 16, 2011. Credit: Theirry Legault. Used by permission.
I was waiting for this, and I know our readers have been looking forward to seeing astrophotographer Thierry Legault’s images of the ROSAT satellite as it heads towards its uncontrolled re-entry through Earth’s atmosphere to its ultimate demise. Legault took a series of images on October 16, 2011 from France and combined them into a video. The speed of the sequences is accelerated 3 times with regard to real time (30 frames per second vs 10 fps). The distance to observer is 275 km, with the altitude of the satellite at 235 km. Angular speed at culmination: 1.66°/s.
“It looks very steady, no sign of tumbling or flares like UARS,” Legault told Universe Today via Skype.
You can compare it to earlier images taken by Legault on September 23, 2011, below.
Legault said he drove 100s of kilometers in order to capture ROSAT, and had to deal with clouds and fog before successfully imaging the satellite.
The latest prediction put out by the German Space Agency (DLR) has the ROSAT satellite re-entering sometime between October 21 and 24. This is a slightly narrower time window than the last prediction, which lasted until October 25. We’ll keep you posted on when and where the pieces of the satellite might fall. Legault told Universe Today that he is hoping ROSAT will provide some nice fireworks right over his location in France!
The video below, taken by Legault on September 23, 2011 at 04:36 UT shows ROSAT at an altitude of 284 km, with distance to observer at 458 km. Angular speed at culmination: 0.94°/s.
NASA, the NRO and the U.S. Air Force have signed an agreement that could see smaller space firms competing for large military contracts. Photo Credit: Alan Walters/awaltersphoto.com
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The United States Air Force has entered into a Memorandum of Understanding or MOU with the National Reconnaissance Office (NRO) and NASA to bring more players into the launch vehicle arena. On Oct. 14, NASA, the NRO and the U.S. Air Force announced plans to certify commercial rockets so that they could compete for future contracts involving Evolved Expendable Launch Vehicle, or EELVs. This means that Space Exploration Technologies’ (SpaceX) could compete for upcoming military contracts.
“This strategy will provide us with the ability to compete in the largest launch market in the world,” said Kirstin Brost Grantham, a spokeswoman with SpaceX. “There are those who are opposed to competition for space launches, they would prefer to see the status quo protected. But SpaceX has shown it is no longer possible to ignore the benefits competition can bring.”
In terms of sheer numbers of launch vehicles purchased – the U.S. Air Force is the largest customer in the world – with the U.S. taxpayer picking up the tab. Therefore it was considered to be in the Air Force’s best interest to find means to reduce this cost. The U.S. Air Force’s requirements are currently handled by United Launch Alliance (ULA) in what is essentially a monopoly (or duopoly considering that ULA is a collective organization – comprised of both Boeing and Lockheed Martin).
The two launch vehicles that ULA provides are the Delta IV and Atlas V family of rockets. Photo Credit: Alan Walters/awaltersphoto.com
“SpaceX welcomes the opportunity to compete for Air Force launches. We are reviewing the MOU, and we expect to have a far better sense of our task after the detailed requirements are released in the coming weeks,” said Adam Harris, SpaceX vice president of government affairs.
The U.S. Department of Defense (DoD) has decided to go ahead with a five-year, 40-booster “block-buy” plan with ULA – despite the fact that the U.S. General Accounting Office’s (GAO) has requested that the DoD rethink that strategy. The GAO stated on Oct. 17, that they are concerned that the DoD is buying too many rockets and at too high of a price.
Under the Evolved Expendable Launch Vehicle Plan, the DoD is set to spend some $15 billion between 2013 and 2017 to acquire some 40 boosters from ULA to send satellites into orbit. For its part, the DoD conceded that it might need to reassess the manner in which it obtained launch vehicles.
As it stand now, United Launch Alliance has a virtual monopoly on providing launch vehicles for the Department of Defense. Photo Credit: Alan Walters/awaltersphoto.com
The new strategy which is set to allow new participants in to bid on DoD and NRO contracts is an attempt to allow the free-market system drive down the cost of rockets. Recently, the price of these rockets has actually increased. The cause for this price increase has been somewhat attributed to the vacuum created by the end of the space shuttle program.
Firms like SpaceX, which seek to compete for military contracts, will have to meet requirements that are laid out in “new entrant certification guides.”
“Fair and open competition for commercial launch providers is an essential element of protecting taxpayer dollars,” said Elon Musk, SpaceX CEO. “Our American-made Falcon vehicles can deliver assured, responsive access to space that will meet warfighter needs while reducing costs for our military customers.” Space Exploration Technologies (SpaceX) CEO Elon Musk applauded the recent announcement that could see his company competing for military contracts. Photo Credit: Alan Walters/awaltersphoto.com
The recent re-entry of the UARS satellite was not the end of falling satellite debris, as the German ROSAT X-ray observatory satellite will soon crash back to Earth.
Last month NASA’s large UARS satellite re-entered the atmosphere and burned up over the Pacific Ocean, with about 500 kg of debris falling into the water. But the smaller Roentgen Satellite or ROSAT will have approximately 30 pieces equaling 1.5 tons that will resist burn up and make it to the surface.
The largest piece of the satellite expected to reach the surface is the heat-resistant, 32 inch, 400 kg mirror.
Compared to UARS, there is an increased chance of someone being hit by a piece of the falling debris. The odds have been estimated as a 1 in 2,000; UARS was 1 in 3,200.
As with UARS, it is unknown where ROSAT will burn up and where its remaining parts will impact the surface, however the satellite is expected to re-enter between the 21st and 24th of October. The Center for Orbital and Re-Entry Debris studies predicts October 23, 2011 a 06:40 UTC ± 30 hours.
Prediction Ground Track Credit: Center for Orbital and Reentry Debris Studies
Until then, you can keep an eye out for the small satellite as it is a naked eye object. It’s nowhere near as bright as the ISS, but it is visible. Check Heavens Above or Spaceweather for predictions of when it will pass over your location.
The 2.4 ton Roentgen Satellite (ROSAT) was launched by NASA in 1990 as a joint venture between Germany, Britain and the USA.
The satellite was designed to catalogue X-ray sources in deep space and mapped around 110,000 stars and supernovae. It also discovered that some comets emit X-rays. It was permanently damaged in 1998, and its mission was officially ended in February of 1999.
ROSAT will soon meet its fiery end; will you see it pass over before then?
Every couple of weeks or so a strange flash appears on an all-sky camera that searches for meteors. What could it be? Take a look at the video above and maybe you can help solve the mystery.
“They are not iridium flares because they are stationary,” said James Beauchamp, an amateur astronomer who hosts the meteor camera for Sandia National Labs and New Mexico State University, and who posted this video on You Tube. “And they are not geosynchronous satellites because the azimuth/elevation are too far North. They are reflective because they always happen just prior to or after sunrise/sunset. Whatever it is, it’s slow and BIG.” Continue reading “All-Sky Camera Captures Mysterious Flashes”
The X-37, versions of which have flown twice into space already, is now being proposed as a potential means of transportation for crews to the International Space Station. Photo Credit: Boeing
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As reported online at Space.com, the Boeing Company is already working on the CST-100 space taxi as a means of transportation to and from the International Space Station (ISS). But the aerospace firm is not content with just this simple space capsule and is looking into whether-or-not another of Boeing’s current offerings – the X-37B space plane could be modified to one day ferry crew to and from the orbiting laboratory as well.
proposed variant of the spacecraft, dubbed the X-37C, is being considered for a role that has some similarities to the cancelled X-38 Crew Return Vehicle (CRV). The announcement was made at a conference hosted by the American Institute of Aeronautics and Astronautics (AIAA) and reported on Space.com.
The USAF has already launched two of the X-37B Orbital Text Vehicles (OTV) from Cape Canaveral Air Force Station in Florida. Photo Credit: ULA/Pat Corkery
The X-37B or Orbital Test Vehicle (OTV) has so far been launched twice by the U.S. Air Force from Cape Canaveral Air Force Station in Florida. One of the military space planes completed the craft’s inaugural mission, USA-212, on Apr. 22, 2010. The mini space plane reentered Earth’s atmosphere and conducted an autonomous landing at Vandenberg Air Force on Dec. 3, 2010.
The U.S. Air Force then went on to launch the second of the space planes on mission USA-226 on Mar. 5, 2011. With these two successful launches, the longest-duration stay on orbit by a reusable vehicle and a landing under its belt, some of the vehicle’s primary systems (guidance, navigation, thermal protection and aerodynamics among others) are now viewed as having been validated. The vehicle has performed better than expected with the turnaround time being less than predicted.
If the X-37C is produced, it will be roughly twice the size of its predecessor. The X-37B is about 29 feet long; this new version of the mini shuttle would be approximately 48 feet in length. The X-37C is estimated at being approximately 165-180 percent larger than the X-37B. This increase in the size requires a larger launch vehicle.
This larger size also highlights plans to have the spacecraft carry 5 or 6 astronauts – with room for an additional crew member that is immobilized on a stretcher. The X-38, manufactured by Scaled Composites, was designed, built and tested to serve as a lifeboat for the ISS. In case of an emergency, crew members on the ISS would have entered the CRV and returned to Earth – a role that now could possibly be filled by the X-37C. The key difference being that the CRV only reached the point of atmospheric drop tests – the X-37B has flown into space twice.
Certain elements of the X-37C proposal highlight mission aspects of the cancelled X-38 Crew Return Vehicle. Photo Credit: NASA.gov
The crewed variant of the X-37 space plane would contain a pressurized compartment where the payload is normally stored, it would have a hatch that would allow for astronauts to enter and depart the spacecraft. Another hatch would be located on the main body of the mini shuttle so as to allow access to the vehicle on the ground. The X-37C, like its smaller cousin, would be able to rendezvous, dock, reenter the atmosphere and land remotely, without the need of a pilot. Acknowledging the need for pilots to control their own craft however, the X-37C would be capable of accomplishing these space flight requirements under manual control as well.
As mentioned in the Space.com article, one of the other selling points for the X-37C is its modular nature. Different variants could be used for crewed flights or unmanned missions that could return delicate cargo from the ISS. Neither the Russian Soyuz spacecraft, nor commercially-developed capsules are considered as appropriate means of returning biological or crystal experiments to Earth due to the high rate of acceleration that these vehicles incur upon atmospheric reentry. By comparison the X-37B experiences just 1.5 “g” upon reentry.
The launch vehicle that would send the proposed X-37C to orbit would be the United Launch Alliance Atlas V rocket. In provided images the X-37C is shown utilizing a larger version of the Atlas booster and without the protective fairing that covered the two X-37B space planes that were launched.
The European Union and European Space Agency (ESA) will launch the first components next week of the €20 billion Galileo global navigation satellite system. This constellation of satellites will allow users to pinpoint their location anywhere on Earth. It will be a free, fully autonomous and interoperable worldwide satellite navigation system, broadcasting global navigation signals for high-performance services, which ESA says possesses the service integrity guarantees that GPS lacks for commercial and safety-critical services.
The first launch is scheduled for October 20, 2011. This 3-D video provides an overview of the system. Use red/blue 3D glasses to watch in 3D.
