ESA ATV-5 Georges Lemaître moves ISS away from Space Debris

A view from the International Space Station with ESA’s Automated Transfer Vehicle 5, Georges Lemaître. 

Credit: ESA/NASA

The International Space Station was threatened by space debris last week but ESA’s Automated Transfer Vehicle 5, Georges Lemaître saved the day by firing its thrusters to push the orbital outpost and its six occupants out of harm's way.

This is the first time the Station's international partners have avoided space debris with such urgency.

Ground stations continuously track space junk, leftover hardware from defunct satellites, for potentially life-threatening collisions.

A fleck of paint can cause major damage travelling at 28 800 km/h. When they raise the alarm, ground teams can move the Station to a safer orbit.

The calculations sometimes take hours, this is rocket science, but fortunately, most of the time, the radar network gives ample warning.

Sometimes a dangerous object can slip through the net or its erratic behaviour makes accurate predictions difficult.

This is where ESA’s Automated Transfer Vehicle 5, Georges Lemaître came in on 27 October.

A piece of a Russian Kosmos-2251 satellite that broke up after colliding with another satellite in 2009 was on a collision course with the International Space Station.

The object was around the size of a hand and calculations showed it would pass within 4 km, too close for comfort.

Just six hours before potential impact, the five space Station agencies agreed to an emergency manoeuvre.

The ATV Control Centre team in Toulouse, France, triggered a boost of 1.8 km/h, enough to raise the 420-tonne Station by 1 km and out of harm's way.

This image of the International Space Station with the docked ESA's ATV-2 Johannes Kepler and Space Shuttle Endeavour was taken by ESA astronaut Paolo Nespoli from Soyuz TMA-20 following its undocking on 24 May 2011. 

Credit: ESA/NASA

Before 2012, if an object was spotted within 24 hours of a potential strike the astronauts returned to their spacecraft, prepared for evacuation and hoped for the best.

Since 2012, emergency manoeuvres at less than 24 hours' notice are possible using Russia's Progress supply ship, but none was in harbour earlier this week.

ATVs have been able to perform this move since last year, starting with ATV-4 Albert Einstein, but its services were not required during its mission.

Although this debris avoidance used a predefined manoeuvre, great care was taken to make sure that the move did not push the Station into a worse orbit or affect the docking of last week's Progress.

"This is what the ATV Control Centre team trains for," said ESA flight director Jean-Michel Bois.

"Seven days a week, 24 hours a day, we are ready to react and we practise often in simulations.

"Reacting so quickly to save the Space Station in real life was tense but rewarding."

ESA’s supply and support ferry ATV-5 Georges Lemaître approaches the International Space Station for docking. 

The fifth and last Automated Transfer Vehicle docked with the weightless research centre on 12 August 2014. 

Credit: Roscosmos–O. Artemyev

In close coordination with the Station's control centres in Moscow, Russia and Houston, USA, the ATV team commanded a four-minute thruster burn starting at 17:42 GMT (18:42 CET).

The helping hand from Georges Lemaître was one of the last tricks up ATV's sleeve. The versatile vessels have achieved many firsts for ESA.

They are the largest European spacecraft ever launched and the only non-Russian vehicle to dock automatically with the Station.

After delivering more than 6.6 tonnes of supplies, fuel and gases, Georges Lemaître will undock in February and burn up harmlessly in the atmosphere, after demonstrating a new shallow reentry for planning Station decommissioning.

Soyuz TMA-03M and Progress as seen by ESA astronaut Andre Kuipers during his mission. Credit: ESA/NASA

"The debris avoidance demonstrates ATV's reliability and the great team behind mission control," concluded ESA's ATV-5 mission manager Massimo Cislaghi.

"With this manoeuvre, ATVs have met every requirement of the original design."

But the versatility does not end there. ATV technology will be a critical part of NASA's Orion, supplying power and life-support for the next generation of crewed spacecraft.

ESA’s supply and support ferry ATV Georges Lemaître approaches the International Space Station for docking. 

The fifth and last Automated Transfer Vehicle docked with the weightless research centre on 12 August 2014. 

Credit: Roscosmos–O. Artemyev

Space debris: Expert warns of increasing CubeSat collision risk

A Clyde-Space CubeSat in the Scottish test lab.

Credit: Clyde-Space

The increasing number of small 'CubeSat' satellites being launched combined with a relaxed attitude to debris mitigation could lead to hazards for all space users unless preventative measures are taken, warns a leading space debris expert from the University of Southampton.

Speaking today at the 65th International Astronautical Congress (IAC) 2014 in Toronto, Dr Hugh Lewis said that this combination leads to a growth in space debris, as a result of collisions between CubeSats and other objects in orbit.

CubeSats are small satellites (around 10x10x10cm) that are providing opportunities for companies to break into the space data and communications industries.

Despite many CubeSats not having any manoeuvring capability so they cannot avoid collisions during the mission or manoeuvre to a disposal orbit at their mission end, they are still perceived to have a low impact on the space debris environment.

However, despite guidelines requiring the satellites to deorbit within 25 years, some are being launched into high Earth orbits, which means their orbital lifetime could be much greater.

More than a third of all CubeSats launched to-date (around 160 between 2003 and 2013) are predicted to remain on-orbit for more than 25 years.

Since 2005, CubeSats have been involved in more than 360,000 close approaches of less than 5 km with other orbiting objects.

Dr Lewis says: "To reduce the risks, some effort is needed to engage with the growing small satellite community."

"All space users, not just those in the CubeSat community, who are taking the right steps should be encouraged to continue and, ultimately, lead on sustainable practices and debris mitigation activities.

"Those who are not yet engaged with this approach should be encouraged to do so. It's probably a matter of changing their perceptions of the risks and helping them to understand that there is a collective responsibility to ensure that outer space activities are sustainable so that future generations have the same opportunities to use space as we do."

Dr Lewis and his team used their Debris Analysis and Monitoring Architecture to the Geosynchronous Environment (DAMAGE) model to simulate three future CubeSat launch traffic scenarios until the year 2043.

By comparing these with close approach data from 2005 to 2013, the team found CubeSats are estimated to be involved in millions of close approaches over the next 30 years, with a handful leading to a collision.

Analysis of the close approaches found that most of the collision risk from CubeSats comes from high-speed encounters with large spacecraft.

In addition, many of these encounters were in Sun-synchronous orbits that are popular with remote sensing and Earth science satellites.

Dr Lewis adds: "By far the greatest risk comes from those with long lifetimes at altitudes of about 750 km. If CubeSats continue to be launched into long-lived orbits without any means of disposing of them, then they will contribute to the growing space debris hazard."

"This is not a responsible or sustainable practice, in my view. However, if efforts are made to limit the lifetimes, as some are already doing, then the risks will be reduced."

Lockheed taps GenDyn unit for Space Fence ground equipment structures

Ground structures for housing the U.S. Space Fence program are to be designed and built by a General Dynamics business unit under contract from Lockheed Martin.

The structures, as well as integration of mechanical systems for the project, will start next year on Kwajalein Atoll in the Republic of the Marshall Islands.

"Just like the precision radio-telescope antennas, General Dynamics C4 Systems SATCOM Technologies' expertise in building exceptionally large, exquisitely engineered structures will contribute to keeping the satellites we depend on for communications, weather forecasting and other services from colliding with space debris," said Chris Marzilli, president of General Dynamics C4 Systems.

Space Fence is a new ground-based radar system for detecting and tracking the more than 100,000 objects currently in space to help avoid collisions. Lockheed is building the radar system for the U.S. Air Force.

General Dynamics C4 Systems SATCOM Technologies is a supplier of base station and Earth station communications products and services, such as satellite antennas and antenna systems and cyber-secure wireless communication products, and also engages in the design and building of advanced optical telescope mirror structures and radio telescope antennas.

Space Debris damages ISS US segment

Space debris has damaged a cooling system radiator of the International Space Station (ISS) U.S. segment in the P4 truss section, the NASA website said. 

It said images of the ISS surface captured by external cameras were being analyzed and data suggests there isn’t an ammonia leak from the system as a result of the 12 inch long puncture to the cover sheet. 

The NASA delegation to the Russian Mission Control Center has offered no comment on the situation. 

The hardware in question is one of the key elements of the heat rejection systems utilized by the orbital outpost.

So far, the ISS does not appear to be suffering any ill effects of the damage, while no leaking from the panels has been observed at this time.

MicroMeteoroid and Orbital Debris (MMOD) strikes on space hardware are not uncommon and continue to be a major risk factor all spacecraft have to deal with.

Such MMOD strikes were observed on a large amount of Space Shuttle missions, especially late into the mission when the orbiter had undocked from the protection of the ISS and was preparing to head home.

The ISS is manned by Russia's Alexander Skvortsov, Oleg Artemyev and Maxim Surayev, U.S. astronauts Steve Swanson and Reid Wiseman and German astronaut Alexander Gerst.

Indian ISRO PLSV rocket launches 5 satellites: Three minute delay to avoid space debris

The Monday morning blast off of an Indian Space Research Organisation (ISRO) PSLV rocket carrying five foreign satellites was delayed by three minutes to avoid a collision with space debris, the space agency said.

Despite the necessary delay, the Polar Satellite Launch Vehicle's (PSLV) carrying the five foreign satellites blasted off from the Indian Space Research Organization’s launch pad at Sriharikota in Andhra Pradesh in southern India at 09:52 a.m. local time.

With this launch, India has successfully put into orbit five foreign satellites from four different countries.

The rocket's main payload was the 714-kg French EADS Astrium Earth Observation satellite SPOT-7.

The other satellites are:

• 14-kg AISAT-1 of Germany (already transmitting signals from orbit); 
• NLS7.1 (CAN-X4) and NLS7.2 (CAN-X5) from Canada's University of Toronto Institute for Aerospace Studies' Space Flight Laboratory each weighing 15 kg (CanX-4 and CanX-5 form a dual nanosatellite formation flying a demonstration mission); and 
• 7-kg, 1U Cubesat VELOX-1 of Singapore.

The five satellites were launched under commercial arrangements that Antrix Corporation has entered into with the respective foreign agencies.

Oppressive China says Express-AM4P satellite space debris recovered

Photo taken on May 19, 2014 shows government technicians preparing to remove space debris that crashed to the ground in Qiqihar, China's Heilongjiang province 

Objects that crashed to the ground in China have been identified as space debris, state media reported, after a Russian rocket carrying a communications satellite fell back to Earth minutes after lift-off.

Qiqihar city in the northeastern province of Heilongjiang, which borders Russia's far east, reported that several objects appeared to have fallen from the sky on Friday, the Xinhua news agency said.

After analysis, experts have concluded they were "parts from a carrier rocket or a satellite", Xinhua said Sunday, citing the China National Space Administration.

Authorities were communicating on the issue "with relevant parties", it added.

The report came after Russia's space officials said the Proton rocket's control engine failed Friday just over nine minutes following blastoff from the Baikonur space centre Moscow leases in Kazakhstan—the latest blow to the country's once-proud space industry.

State television showed the carrier and its Express-AM4P satellite burning up in the upper layers of the atmosphere.

The space debris that crashed to the ground in Qiqihar, China's Heilongjiang province, pictured on May 19, 2014

The 150-million-euro ($205-million) satellite, built by EADS Airbus Group's Astrium corporation, was meant to provide Internet access to far-flung Russian regions with poor access to communication.

ESA Clean Space: Reducing debris threat from satellite batteries

So far, about 200 explosions and at least 5 collisions in space have occured. 

Further explosions and collisions are very likely. 

The explosions are mainly caused by onboard energy sources, either due to pressure build-up in propellant tanks, battery explosions, or the ignition of hypergolic fuels. 

Each explosion creates thousands of small debris objects. 

The most prominent collision event and the first known one between two catalogued objects was in 1996 between the French Cerise Satellite and a fragment of an Ariane upper stage explosion. 

Credit: ESA

Across a satellite's working life, batteries keep the craft's heart beating whenever it leaves sunlight. But after its mission ends, those same batteries may threaten catastrophe.

Space debris mitigation rules require the complete deactivation of electrical power sources aboard a satellite on retirement, to guard against explosive accidents that might produce fresh debris dangerous to other satellites.

Now a new study by ESA's Clean Space initiative – tasked with reducing the space industry's environmental impacts on both Earth and space – aims to evaluate battery behaviour after a satellite shuts down, assessing the risk of breakup and ensuring full 'passivation'.

Batteries are among a satellite's bulkier items of equipment. Typically, they feed their host with power during launch.

Once in orbit, it switches to power from its solar arrays, but the battery is an important backup to store power for eclipses and emergencies.

To reach the high reliability and performance a satellite demands, extending across many months or years, batteries are carefully designed and extensively tested in advance of launch.

By contrast, their behaviour after their parent mission has been shut down remains a relative blind spot.

As a satellite drifts freely, could batteries endure the harsh environment of orbit – including wild temperature swings, degradation of thermal control and components as well as radiation exposure – without leakage or bursting?

Some past satellite breakups have been triggered by battery malfunctions, although mostly before the 1990s and involving older non-lithium designs.

This multidisciplinary study aims to ensure a fully inert power system at the end of a mission, perhaps through physical disconnection, while also preventing accidental premature passivation.

ESA ENVISAT: De-orbiting and space debris threat from giant satellite

Artist's impression of Envisat orbiting the Earth. Credits: ESA

Physics students at the University of Leicester have pointed out that ESA's huge observational satellite Envisat, which lost contact with Earth in 2012, could potentially pose a space debris threat to the Earth.

What's more, the task of bringing the satellite back to Earth may be too costly and complex to be feasible, according to their final year paper for the Journal of Physics Special Topics, a peer-reviewed student journal run by Leicester University's Department of Physics and Astronomy.

Envisat, an £1.8 billion, 9 metre-long behemoth, was launched by the European Space Agency (ESA) in 2002, and used ten sophisticated sensors to observe and monitor Earth's land, atmosphere, oceans and ice caps.

However, ESA lost contact with the satellite in April, 2012 and declared the end of the mission soon after.

The satellite now orbits the Earth free from human control at an altitude of 790km, where the amount of space debris around the planet is greatest.

This means there is a greater chance of collision with other satellites and debris during the 150 years it is expected to remain in space.

Each year, two objects are expected to pass Envisat to within about 200m and other spacecraft have had to move out of Envisat's path.

It is possible – though unlikely - that a collision with Envisat could lead to a chain reaction effect, known as the Kessler Syndrome, where a cloud of fast-moving debris causes other collisions with orbiting bodies around the Earth.

This would not be good news for the many essential satellites and spacecraft in orbit.

It could also make it difficult for future space missions to pass through the region of Envisat's altitude, if the region becomes congested with space debris.

The fourth-year MPhys students' paper, 'De-orbiting Envisat', suggests that around 140kg of fuel would be required to move the satellite to a point where it would naturally return to Earth within 25 years.

Based on the object's cross-sectional area and its mass, the students calculated that the satellite would need to be moved to an altitude of 700km from its current position in order to return to the planet in 25 years.

The students calculated that the energy required to move the satellite 90km closer to the Earth was 2.7 billion joules, equivalent to an extra 143.1kg of hydrazine fuel.

This could be quite feasible, according to the students, if two of the craft's 80kg fuel tanks were replaced.

But actually getting this fuel to the satellite in orbit would be a pretty tall order due to the costs involved of such a mission – which has never been attempted for a satellite which wasn't designed to be refuelled.

More information: "De-orbiting Envisat." K. Raymer, T. Morris, O. Youle, B. Jordan, Department of Physics and Astronomy, University of Leicester, Leicester, LE1 7RH. physics.le.ac.uk/journals

Space Debris: Ecuador Pegaso satellite collides with Russian rocket remains

An Ecuadoran satellite launched last month, with the help of China, has collided with the remains of a Russian rocket in the coming hours, the country's civilian space agency warned Wednesday.

The "Pegaso" (Pegasus) nanosatellite, designed and built in Ecuador, set off aboard an unmanned rocket April 25 from the Jiuquand station in northern China. It is the country's first.

The Joint Space Operations Center in the United States, which monitors all artificial Earth-orbiting objects, said there had been no head-on crash but "data indicated a lateral collision with particles" of the Soviet-era rocket.

"Pegasus could be damaged or spinning out of control but, because it's still in orbit, we have hope," Ronnie Nader, head of the Ecuadorian Civilian Space Agency, tweeted.

"Ecuador still has its satellite, the people still have Pegasus," he wrote, saying it could take up to 48 hours to assess damage.

The 2.6-pound nanosatellite had been orbiting at a distance of 404 miles while transmitting pictures of the Earth.

Measuring just 10 by 10 by 75 centimeters (four by four by 30 inches), and weighing 1.2 kilograms (2.6 pounds), Pegaso on Thursday transmitted its first live video with audio.

Last month's launch came amid much fanfare, including a live broadcast.

The South American country plans to send a second satellite into space from Russia in July.

Space Station Solar Array Damaged by Space debris or Meteoroid

A small object, possibly a meteoroid, has flown through a solar panel on the International Space Station, leaving a "bullet hole," Canadian astronaut and Expedition 35 commander Chris Hadfield has said.

"Bullet hole - a small stone from the universe went through our solar array. Glad it missed the hull," Hadfield wrote in his Twitter blog, revealing a photo of the damage he took during a recent EVA or "space walk" around the ISS.

However, experts believe the hole was probably caused by a random object, possibly space junk, which would not have been able to penetrate the layers of the station's hull.

Jim Scotti, a planetary scientist at the University of Arizona's Lunar and Planetary Laboratory, said: "It's unlikely this was caused by a meteor, more likely a piece of man-made space debris in low Earth orbit."

ESA announce 6th European Conference on Space Debris - Collision Video

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Esa's Heiner Klinkrad of TU Braunschweig, just opened the 6th European conference on Space Debris in ESA's ESOC installation in Darmstadt, Germany,

Space Debris: Space Fence to be extended

The Raytheon designed Air Force Space Surveillance System, also  known as Space Fence.

The incremental reviews included overall system design and architecture, radar hardware and software configuration items, allocated baseline, logistics, facilities, test, modeling and simulation along with the radar prototype demonstration.

Following the reviews, the contractors worked on risk reduction activities and design maturation.

The Air Force Life Cycle Management Center here recently put out a request for proposal to move the Space Fence program forward.

Space Fence will be a system of up to two land-based radars, the first site located at Kwajalein Atoll in the Marshall Islands, to track objects entering Earth's orbit.

According to program officials, it will form the foundation of improved space situational awareness by expanding the ability to detect, track, identify and characterize orbiting objects such as commercial and military satellites, smaller objects, maneuvering satellites, break-up events and lower inclination objects.

"Space situational awareness is a continual concern and challenge for U.S. and ally nations," said Ken Francois, Space Fence program manager. 

"The Space Fence program will increase the capability to provide predictability in reducing the chance of a collision or attack."

During a Defense Acquisition Board held in August, some changes were made to the program's acquisition strategy.

"The most significant change is that we are moving to an incremental approach. Increment 1 includes the Space Operations Center and Site 1 facilities construction and radar build," said Francois.

"Increment 2 includes Site 2 and system integration. This approach maximizes our efficient use of resources and will allow us to reduce costs to the Defense Department and the Air Force, ultimately saving money for the taxpayer."

North Korean Satellite Tumbling and now Space Debris

Kwangmyongsong-3, the North Korean satellite launched into space by the Unha-3 rocket last week, is out of control and most likely dead, astronomers reported Monday.

The apparent failure will not cause the spacecraft to fall quickly back to earth but represents a major setback in Pyongyang’s bid to portray the launching as a patriotic and technological success.

“It’s tumbling and we haven’t picked up any transmissions,” said Jonathan McDowell, a Harvard astronomer who tracks global rocket launchings and space activity. “Those two things are most consistent with the satellite being entirely inactive at this point.”

North Korea’s state-run press, which was preoccupied on Monday with reporting on the somber one-year anniversary of the death of Kim Jong-il, the longtime leader, said nothing about the satellite’s dysfunction.

It has been describing the satellite launch as a triumphal achievement of Mr. Kim’s successor, his son Kim Jong-un, done in the face of worldwide criticism and United Nations sanctions on the North’s ballistic missile program.

The satellite, said to be about the size of a washing machine, reportedly carries an onboard camera to observe the earth. That mission requires the spacecraft’s orbit to be rock-steady.

Dr. McDowell said the tumbling implies that onboard systems meant to control and stabilise the craft had failed.

He added that radio astronomers had picked up no signals from the satellite and that optical astronomers had observed it brightening and dimming as it slowly tumbled end over end.

“It’s clear that the rocket part of this mission worked very well for the North Koreans,” Dr. McDowell said in an interview.

“They ended up in the right orbit. But the preponderance of the evidence suggests that the satellite failed either during the ascent or shortly afterwards.”

Space Debris: New ESA European Radar Installation

A new radar designed to test methods for finding orbital debris that can be hazardous to space navigation has been installed near Santorcaz in Spain.

The radar will be used to develop future debris warning services, helping to improve safety for ESA's European satellite operators

AEOLDOS: Glasgow Uni and Clyde Space set to put brakes on SpaceDebris

Engineers at the University of Glasgow and Clyde Space Ltd have developed a practical solution to the increasing problem of space debris. Millions of pieces of 'space junk' are orbiting the Earth as a side-effect of human exploration and exploitation of space.

The pieces range from tiny fragments of bigger objects such as rocket boosters to full-sized pieces of now-defunct equipment. Working satellites and spacecraft can be damaged by collisions with debris, which can travel at velocities of several kilometres per second.

The problem is compounded by every collision which creates more debris in turn; in 2009, the collision of a non-operational Russian communications satellite and a working US satellite created more than 700 pieces of debris.

Dr Patrick Harkness of the University's School of Engineering has led the development of the Aerodynamic End Of Life Deorbit System, or AEOLDOS, to help ensure that objects sent into space in future can be removed from orbit at the end of their operational cycle.

AEOLDOS is lightweight, foldable 'aerobrake' which can be added to small satellites known as CubeSats before they are launched into low Earth orbit.

Once the satellite has reached the end of its operational life the lightweight aerobrake, made from a thin membrane supported by tape measure-like struts, springs open to generate aerodynamic drag against the extremely thin upper atmosphere that still exists in near-Earth space.

As the satellite falls out of orbit the aerodynamic effects increase, causing the satellite to harmlessly burn up during its descent.

This ensures that it does not become another piece of potentially harmful space debris.Glasgow-based SME Clyde Space, which builds small and micro spacecraft systems, is working with Dr Harkness to apply AEOLDOS technology to the CubeSats it provides to customers all over the world.

CubeSats are used for space-related research projects and generally sent into space as secondary payloads on larger launch vehicles.

Dr Harkness said: "It's only been 55 years since Sputnik, the first man-made satellite, was sent into orbit, but since then we've managed to make made quite a mess of the space around our planet.

The rate at which we're putting objects into orbit is accelerating each year, which is why it's vital for us to take more control over how they can be removed from orbit once they have served their purpose.

CubeSats are currently aimed at lower orbits than is necessarily desired to ensure they will re-enter the Earth's atmosphere within 25 years in order to meet official recommendations set by the United Nations Office for Outer Space Affairs.

This can curtail the full scientific potential of CubeSats, but AEOLDOS gives users much more control over the end of their project's life and could enable missions to take place at much higher altitudes because they know we can always produce the drag they will need to dispose of the spacecraft in time."

The tape measure deployment system has been developed by Malcolm McRobb, also from the School of Engineering.

Coiling the tapes stores energy within them, which can be released years later to deploy the membrane. Mr. McRobb believes that AEOLDOS has applications beyond space debris control.

He explained: "The technology could be used to enable solar sailing missions, where spacecraft can manoeuvre using the pressure of sunlight.

Or it could form the basis of deployable antennae, increasing the sensitivity of small, low-powered spacecraft.We expect that another year to 18 months of development will see the AEOLDOS system available for commercial use through our licensing agreement with Clyde Space.

After we have demonstrated that the technology can work in space, we are looking forward to designing these new and exciting applications for the device."

Craig Clark of Clyde Space said: 'Clyde Space is widely recognized for developing key technologies and products that enable more advanced CubeSat missions, and AEOLDOS is another key innovation that will enable more spacecraft missions in the future.

The team at the University of Glasgow have been able to solve critical problems relating to the drag sail deployment with effective, innovative solutions and we're sure that this development will be used on many small satellite missions in the future as we aim to reduce the problem of space junk for the next generation of space users.'

The development of the AEOLDOS project is part of the University of Glasgow's Space Glasgow Research Cluster, which draws together researchers from across the College of Science and Engineering to work on pioneering space-related projects.

Space Debris: French Corporation use UK design to 'harpoon' old satellites

UK engineers are developing a system to harpoon rogue or redundant satellites and pull them out of the sky.

It is a response to the ever growing problem of orbital junk - old pieces of hardware that continue to circle the Earth and which now pose a collision threat to operational spacecraft.

The harpoon would be fired at the hapless satellite from close range.

A propulsion pack tethered to the projectile would then pull the junk downwards, to burn up in the atmosphere.

"Space has become a critical part of our infrastructure - from weather forecasting and Earth observation, to GPS and telecommunications," said the harpoon's designer, Dr Jaime Reed, from French corporation EADS Astrium (UK).

"Space junk poses a real threat to these vital services if we do nothing about it, and so it's very important we develop capture technologies to remove some of this material. Studies have shown that taking out just a few large items each year can help us get on top of the problem."

Dr Reed's proposal is for a barbed spear about 30cm in length. It would be mounted on a "chaser satellite" that would edge to within 100m of a junk object.

Pictures sent to the ground would then be used to assess the target, before the chaser was moved to within perhaps 20m to take a shot.

Once the harpoon is hooked through the skin of the rogue satellite or rocket stage, the chaser could either pull on a trailing polymer cord itself or deploy a separate thruster unit to do the job of dragging the aimless drifter towards Earth.

Explosive concern
This is research in its very early stages. The BBC has filmed firing tests of a prototype harpoon at Astrium UK's Stevenage base.

EADS, the largest space manufacturer of aerospace and weapons in Europe, is also pursuing other ideas at its centres in France and Germany.

These concepts involve nets and robotic grappling devices. All systems have their pros and cons.

Harpoons could deal well with a satellite that is tumbling, for example, but the approach has its critics because of the fear it could actually add to our problems in space.

"Historically, one of the great sources of debris has been the explosion of fuel tanks in spent rocket stages," explained Dr Reed.

"We obviously don't want to be the cause of that, so our harpoon has a crushable cylinder. It's like a piston, and as soon as the harpoon hits the satellite wall, it rapidly decelerates, ensuring we don't travel right through the spacecraft, puncturing the tanks."

More than 50 years of space activity have left a huge quantity of redundant hardware in orbit.

This includes not just whole satellites and the upper-stages of the rockets used to put them there, but also debris from fuel tank explosions and nuclear powered devices.

NASA Tracking Space Debris inside International Space Station Safety Zone

Sunlight glints off the International Space Station with the blue limb of Earth providing a dramatic backdrop in this photo taken by an astronaut on the shuttle Endeavour just before it docked after midnight on Feb. 10, 2010 during the STS-130 mission.

CREDIT: NASA

NASA is keeping a close eye on two pieces of space junk expected to whiz by the International Space Station in back-to-back passes, and the station may even have to dodge the orbital debris.

The drifting space flotsam includes the remains of a Russian Cosmos satellite and a leftover chunk of an old Indian rocket.

The Russian satellite debris will creep close to the space station on Thursday morning (Sept. 27), with the Indian rocket remnant zooming by on Friday, NASA officials reported.

As a precaution, NASA and its Russian partners began planning for a possible "debris avoidance maneuver" on Thursday morning that would steer the station clear of both pieces of space debris.

The maneuver, if ultimately required, would fire the thrusters on a European cargo ship currently docked at the station for just over two minutes to move the station clear of the space junk.

NASA and its partners traditionally order a debris avoidance maneuver when a piece of space junk is expected to pass so close that it enters a safety perimeter shaped like a pizza box that extends just over 15 miles (25 kilometers) around the space station, and a half-mile (0.75 km) above and below the orbiting lab.

NASA spokesman Rob Navias of the Johnson Space Center, home to the agency's space station Mission Control center, reported the two space debris fragments being tracked now will come just inside that safety zone.

Navias said the avoidance maneuver would be performed at 8:12 a.m. EDT (1218 GMT) on Thursday, if ultimately required.

It is possible that additional tracking of the space junk may allow station flight controllers to call off the maneuver, he added.

The Russian satellite debris will make its closest approach to the space station on Thursday at 10:42 a.m. EDT (1432 GMT), with the Indian rocket debris passing by on Friday at 1:47 a.m. EDT (0547 GMT), he added.

At no time will the station's three-person Expedition 33 crew be in danger, NASA officials said. The station is currently home to NASA astronaut Sunita Williams, Japanese astronaut Akihiko Hoshide and Russian cosmonaut Yuri Malenchenko.

Spheres: Developing a Space Debris Removal Skill - YouTube

In-orbit rendezvous is a potential solution to address space debris removal, considered to be the predominant issue facing the arena of outer space security and safety.

DARPA, the US Defense Advanced Research Projects Agency, is using an unusual resource to develop rendezvous capability with out of control satellites: a high school competition.

“The control procedures that were developed for the Zero Robotics Challenge will certainly benefit the Phoenix program,” said Dave Barnhart, DARPA program manager.

He was referring to DARPA’s defunct satellite recycling project, “but they also potentially have much wider implications for space-based technologies.”

Participants in the Zero Robotics Autonomous Space Capture Challenge designed algorithms to control a bowling-ball-sized programmable satellite known as SPHERES.

There are three SPHERES currently aboard the ISS for use in such experiments in an environment where there is no risk of losing the test subjects.

The algorithms were applied across three different scenarios in which the SPHERES satellite simulated an active spacecraft approaching an object tumbling through space.

The Synchronized Position Hold, Engage, Reorient Experimental Satellites (SPHERES)

Through the Phoenix program, DARPA aims to catch retired communication satellites in geosynchronous orbit in order to collect and re-use some of their components.

To do this, the Phoenix spacecraft will have to perform a delicate dance to safely synchronize movements with tumbling satellites and to be able to deploy tools and attach or remove targeted parts.

Extended use of such a technology could allow the removal of more general space debris like fragments from collisions and exploded rocket bodies or objects from extravehicular activities.

Space Debris: Legal issues surrounding remediation

Desperately seeking Technical solutions to the orbital debris problem, like the Swiss CleanSpace One, also require changes to the legal regime. (credit: EPFL)

Space debris is considered by many to be the most prominent issue in the arena of outer space security and safety.

More than a half-century of space activities by the various spacefaring nations have left a debris environment that is self-perpetuating and threatens to render the outer space environment useless, particularly in low Earth orbit.



Space debris ranges in size from fragments less than a millimeter in diameter to complete spacecraft many meters across. The nature of this debris includes intact satellites, rocket bodies, fragments from exploded rocket bodies, fragments from collisions, and objects from extracurricular activities.

Addressing the issue of space debris is two-fold. First, there is mitigation, which through practices by space-faring nations such the space debris mitigation guidelines promulgated by the UN.

These guidelines are not binding upon member states of the UN and only a few of the spacefaring nations have implemented them as mandatory requirements into their space programs.

However, remediation or removal of existing space debris is another matter, and the methodologies of which are still in its infancy and face substantial technical, financial and political hurdles. Additionally, space debris remediation also faces major legal issues.

The purpose of this essay is to attempt to identify and briefly discuss some of those legal challenges and their potential solutions, including a definition of space debris that could facilitate space debris remediation. This essay is should not be considered and exhaustive discussion on the topic.

The most prominent issue surrounding cleanup of orbital space debris rests with Article VIII of the Outer Space Treaty, in which space objects, including nonfunctioning satellites and other space debris, continue to belong to the country or countries that launched them.

There is no right of salvage analogous to the right found in maritime law, which means that even though a satellite or some other space object may not be functioning, it does not imply that it has been abandoned by the nation that launched it.

Without consent from the nation that launched and operates or otherwise owns the satellite or space object, it cannot be disposed of or otherwise interfered with.

This is further complicated by the fact that international space law deems fragments and components from space objects as individual space objects in and of themselves, which would require identification to determine the owner and either individual or blanket consent to remove it from orbit.

Read the full report here: 

ESA’s Clean Space targets orbital debris and greener environment

70% of all catalogued objects are in low-Earth orbit (LEO), which extends to 2000 km above the Earth's surface. 

To observe the Earth, spacecraft must orbit at such a low altitude. 

The spatial density of objects increases at high latitudes.

Note: The debris field shown in the image is an artist's impression based on actual data. 

However, the debris objects are shown at an exaggerated size to make them visible at the scale shown.

Credits: ESA

Next year’s Hollywood film Gravity features George Clooney stranded in orbit by cascading space junk. The threat is genuine, with debris levels rising steadily.

ESA’s new Clean Space initiative is developing methods of preserving near-Earth space – and the terrestrial environment, too.

Responding to public environmental concerns, Clean Space aims to reduce the environmental effect of Europe’s space activities, cutting waste and pollution on Earth and in orbit.

Industry is contributing to ESA’s draft plans for developing Clean Space technologies: new tools to assess environmental effects, more eco-friendly replacements for materials and techniques, and ways to halt the production of more space debris and bring down existing debris levels.