Date: February 26, 1995
Source: New York Times
Abstract: In the first major case of nuclear pollution in space, a team of American scientists has found that puzzling clouds of junk orbiting the Earth are made up of radioactive debris leaking from orbiting nuclear reactors once used by the Soviet Union to power spy satellites.
The atomic debris poses no danger to humans, experts say. But it
threatens to damage working satellites and will force engineers to add more
shielding to help protect new spacecraft. Experts say the episode drives home
the dangers posed by millions of other bits of manmade debris in space (New York Times, 1995).
Title: Radioactive Debris In Space Threatens Satellites In Use
Date: February 26, 1995
Source: New York Times
Abstract: After sifting clues for five years, a team of scientific sleuths has found that puzzling clouds of junk orbiting the Earth are made up of radioactive debris leaking from a large group of orbiting Russian nuclear reactors. It is the first major case of nuclear pollution in space and one of the messiest environmental legacies of the cold war.
The atomic debris, estimated at 70,000 detectable particles and perhaps millions of smaller ones, poses no danger to humans, experts say. But it threatens to damage working satellites and will force engineers to add more shielding to help protect new spacecraft.
The cloud is seemingly destined to grow, though by how much is unclear.
"We're worried about it," Dr. Donald J. Kessler, the senior scientist for orbital debris studies at the National Aeronautics and Space Administration, said in an interview. "It looks like it could be pretty bad."
Experts say the episode drives home the dangers posed by dead satellites, shattered rocket stages and millions of other bits of manmade debris that speed around the Earth in an orbital junkyard.
For more than two decades, starting in 1967, nuclear reactors were used by the Soviet Union to power low-flying radar satellites that spied on the movements of Western warships. The nuclear reactors made more electricity than the solar cells of regular satellites, allowing the use of energy-hungry radar equipment.
In all, 33 nuclear-powered spy satellites were launched into orbits about 150 miles above the earth, where they worked for a few months at best before their reactors were switched off.
As a safety precaution, Moscow boosted the old reactors into parking orbits roughly 600 miles up, keeping them from re-entering the atmosphere for hundreds of years and allowing their most deadly nuclear fission products to decay. Sending the reactors higher than that, into less-crowded orbits, would have required more fuel and was probably the main factor that made the parking orbits relatively low.
In 1978 a complete failure brought one satellite crashing down on
northern Canada, scattering radioactive debris across the tundra. The last of
the spy class quit working in 1988.
The first hint of trouble came in the late 1980's as NASA began detailed studies of orbital debris in preparation for building a large space station, which was seen as potentially threatened with damage or destruction by space junk.
NASA wanted finer resolution in its images of the sky than was available from the military radar units that hunt for speeding enemy warheads, which at best can detect objects down to a diameter of about 20 centimeters, or roughly 8 inches.
In 1989, as part of this undertaking, a big NASA dish antenna in the Mojave Desert in California was fashioned for radar use and soon detected a swarm of mysterious debris about 400 miles up. Later analysis linked it to Cosmos 1900, one of the Soviet radar satellites that failed to reach its parking orbit 600 miles up.
NASA's investigative powers increased markedly in 1990 when it began getting regular deliveries of data from a 100-foot dish radar in Tyngsboro, Mass., that is run for the Defense Department by the Lincoln Laboratory of the Massachusetts Institute of Technology.
Known as Haystack, it can search through space to find the proverbial needle -- objects a centimeter or less in length, or smaller than half an inch. And it does so over distances of more than 600 miles.
Almost immediately, Haystack began to find signs of widespread debris, which were strongly at odds with theoretical predictions of small objects.
The band of debris extended from 850 kilometers to 1,000 kilometers from the Earth's surface, or from about 530 miles to 620 miles high. It was most densely packed around 600 miles up, suggesting that it was not the product of a blast or catastrophic collision.
"If that had been from explosions, it would have spread out," said Dr. Eugene G. Stansbery, a scientist at NASA's Johnson Space Center in Houston who analyzes the Haystack data. "So we knew it was low-velocity debris."
Another part of the puzzle fell into place as the scientists pointed the Haystack radar in different directions to discover the inclination of the debris band in relation to the Equator. It turned out to be 65 degrees -- the same as that of the Soviet reactors' orbit.
The puzzle was nearly completed by a polarization study of the Haystack data. The radar receives two kinds of polarized waves from its targets, principal and orthogonal. The study showed that the mysterious debris had only principal polarizations, a signature of round objects.
Closing in for the kill, Dr. Kessler and his colleagues at the Johnson Space Center studied published designs of the Russian space reactors and found that they were filled with sodium-potassium coolant -- the only liquid aboard the craft in sufficient quantities to account for an estimated mass spread through space of about 66 pounds.
A final bit of evidence came from a bus-size science satellite known as the Long Duration Exposure Facility, or L.D.E.F., which space shuttle astronauts picked up in 1990, after it had been exposed to the hazards of space for six years. Dr. Kessler asked the team of scientists who worked on that satellite to look for tiny impact pits coated with sodium-potassium. Two were found.
Last year, the NASA team asked the Government to query the Russians about the possibility that their old reactors were leaking. "The answer," Dr. Kessler said, "was yes."
In January, Dr. Kessler and his colleagues, including Dr. Stansbery, Dr. Robert C. Reynolds, Dr. Mark J. Matney and Dr. Phillip D. Anz-Meador, presented two papers on the nuclear debris at a public meeting in Reno, Nev., of the American Institute of Aeronautics and Astronautics, a professional society based in Washington.
The debris, Dr. Kessler said in an interview, is too high to disturb the planned space station. But it will force designers to take new precautions to shield satellites. Among the unknowns, he added, are how much more of the coolant is likely to dribble out in the coming years and decades. So far, only a tiny fraction has leaked. The great corrosiveness of the sodium, he said, gives no cause for optimism.
Dr. Kessler said a meeting with the Russians was scheduled for March to try to learn more about the design of the abandoned reactors and prospects for more leakage.
"We're worried about it," he said. "That's why were asking the Russians questions about the fluid and the long-term prognosis" (New York Times 1995).Title: Space Junk Problem Rising To New Heights
Date: November 20, 2006
Abstract: This week, a spacewalking cosmonaut will tee up a golf ball just outside the international space station and let loose with a publicity-generating drive – a shot that has already generated a debate over the dangers posed by orbital debris. But if you think one foam-rubber “golf ball” is a cause for concern, how about a concert grand piano?
That’s roughly the size and weight of the piece of equipment NASA plans to throw over the space station’s side next spring — if they can figure out which way it’ll go once it’s cast away.
The 1,430-pound (650-kilogram) unit is called the EAS, or Early Ammonia Servicer. It was installed in mid-2001 as an emergency reserve for the station’s coolant system. Once the mature thermal control system is activated next month during Discovery's STS-116 mission to the space station, the EAS becomes surplus space hardware.
NASA had originally planned to bring the EAS back to Earth inside a returning space shuttle — but the subsequent tightening of shuttle cargo manifests in the face of a hard “stop flying” date of 2010 eliminated that option. Keeping the apparatus (and its potential hazardous liquids) attached is also not a safe option. So NASA developed a tentative plan to jettison it manually during the STS-118 mission next July, and now are considering moving that up to the STS-117 mission in March.
Just Push It?
NASA orbital analysts originally thought that the safest way to do so was to push it away from the station manually in the direction opposite the station’s motion. This worked fine last spring for SuitSat, a worn-out spacesuit that was hooked up with amateur-radio equipment to become an experimental satellite. SuitSat fell behind and below the space station, then slipped into a lower but faster orbit, and passed safely beneath. Month by month, SuitSat continued to fall, never threatening a collision with the station.
The problem with EAS, which makes it different from every other object deliberately or accidentally separated from any previous human-occupied space station, isn’t just that it’s heavy. It's also dense. It is, in fact, denser than the space station, which gives it a ballistic number — the degree to which anobject resists air drag, measured in mass per cross-sectional area — up to twice as high, depending on which side of the EAS faces “into the wind” of the thin atmospheric drag at that altitude.
Instead of dropping into a lower, faster orbit, the EAS will hold its momentum better than the station, and the station will drop faster and pull ahead. So far, so good — but the station needs to maintain its perpetually decaying altitude through repeated reboosts. Keeping track of the derelict EAS looming in its higher orbit could significantly complicate navigation at Mission Control in Houston.
Practicing ‘Safe Separation’
Meanwhile, just the physical process of casting EAS loose has been a challenge. Spacesuited astronauts have been practicing “safe separation” for more than a year in test facilities at NASA’s Johnson Space Center. For practice, they have used a frictionless air-bearing table, where the astronauts as well as the objects they're manipulating ride on cushions of air that provide no resistance to horizontal motion.
Slideshow: Summer delights from outer space From this experience, a plan has emerged. In space, the shover-astronaut will stand on a platform attached at the end of the station’s robot arm, while another astronaut undoes the EAS’s restraint bolts. Once it’s free, the astronaut on the robot arm is supposed to use his or her hands to push the unit gently toward the station's back end. Too forceful, and the safety relief hinge of the arm’s platform will fold away; too gentle, and the EAS might not clear the station's structures on its way out.
Specialists had calculated that a 2-inch-per-second (5 cm/sec) push and a departure angle within 30 degrees to the station's orbit ought to be adequate for near-term safety. Since astronauts have regularly achieved rates up to four times faster with much tighter angular precision, getting rid of the unit no longer poses a clearance challenge. But the problem of keeping the unit at a safe distance has grown more serious as analysts realized how the EAS would behave after it’s jettisoned.
‘Honey Buckets’ Keep Falling on Our Heads
Deliberate disposal of garbage from manned space stations in the 1970s and 1980s was the rule, not the exception — and experience indicated it was safe. If the trash dumps departed in a safe direction, air drag effects made them descend into lower orbits. Conversion of potential energy (altitude) into kinetic energy (speed) made them speed up and pull ahead of their former homes, but they never would get high enough to threaten recontact.
The Russians even installed a trash airlock for the regular disposal of food containers, dirty clothing, small items of failed equipment, and sealed fecal filters from their space toilet. When military trackers at the North American Aerospace Defense Command, or NORAD, detected new subsatellites drifting away from Soviet space stations, they would catalog the blips and humorously refer to them as "honey buckets" (an old, old euphemism, most recently an aviation term for the spartan latrine in the back end of an aircraft).
Even on Mir in the mid-1990s, space littering was the accepted practice. NASA astronaut Shannon Lucid, who spent half a year aboard the station in 1996-1997, recalls being astonished to see her Russian shipmates “Yuri and Yuri” (as she affectionately referred to them – Yuri Usachev and Yuri Onufrienko, who both later commanded expeditions on the international space station) gray-taping together masses of surplus packaging foam a few days before any scheduled spacewalk. Once in the airlock, they shoved the 3- to 4-foot-long (meter-long) conglomerations out the hatch and tossed them overboard.
The Past and Future of Space Junk
These activities, aside from giving earthside radar operators more blips to catalog, did no real harm. The reason is that the air drag, even at the 220-mile (350-kilometer) average altitude of the space stations, was enough to inexorably rob this litter of its orbital energy, causing them to slip lower and lower, and burn up within months. Even large, heavy pieces of Russian station-related hardware that were left in orbit could be safely tracked during the several years it took them to slip from space.
The same has been the case with the typical pieces of junk that have come off the international space station. However, the availability of earthbound cargo space in the shuttle (which brings it all the way home) and to a lesser extent in the forward holds of departing Progress and Soyuz vehicles (which are jettisoned to burn up in the atmosphere) has discouraged the policy of throwing stuff out from the station itself.
The space junk problem posed by the piano-sized EAS is just the first of its kind, and it won't be the last. In years to come, when the shuttle stops servicing the station and other vehicles come on line, none will have the down-cargo capacity of the Columbia-class winged orbiters. Big pieces of the station, perhaps replaced by large structures sent up on new launch vehicles and space tugs, will have to be disposed of along the same path that the EAS will soon pioneer.
It’s a harbinger of big space junk problems in the next decade — so getting it right this first time may be critical to planning for the international space station's future (MSNBC, 2006).Title: Swiss Scientist On A Mission To Clean Up Space
Date: October 1, 2007
Source: Swiss Info
Abstract: Fifty years of space activity have left a huge field of rubbish above our heads: rocket stages, satellite fragments, paint flakes – even an astronaut's glove.
Professor Thomas Schildknecht of Bern University's Astronomical Institute is involved in monitoring the skies in a bid to resolve the growing space junk problem.
There are thought to
be more than 600,000 pieces of rubbish of one centimetre or bigger zipping
around our planet at thousands of kilometres per hour.
Space junk has become a growing concern in recent years, as collisions at orbital velocities could have catastrophic consequences for satellites, astronauts and spacecraft, and could also cause a domino effect, resulting in even greater amounts of debris.
At lower orbits (below 2,000km), a centimetre-sized speck of debris speeding along at 15 kilometres per second that hits an operational satellite has damage potential similar to a grenade.
"If you talk about lower orbits, where you've got space stations and manned missions, the issue is quite serious. For the International Space Station, for example, people say there is a 50 per cent chance within the next ten years that the station gets seriously hit by space debris," Schildknecht told swissinfo.
Nasa researchers say a critical space junk tipping point is approaching. Even without launching any additional spacecraft, the number of new fragments created by collisions will exceed the number falling back to Earth and burning up by 2055.
Clearing up the mess in space can therefore seem like a monumental task.
"Nowadays there is no feasible mid-term way of actively cleaning up space, with a vacuum cleaner or whatever," Schildknecht said.
Most international efforts are therefore focused on preventing collisions by keeping track of larger debris, and avoiding creating more.
Using optical telescopes, over the past eight years the Swiss scientist and his team have been monitoring the skies from Bern and the Spanish island of Tenerife, in collaboration with the European Space Agency, building up an inventory of small debris shooting across the skies at high altitudes.
"We see strange types of debris: insulation blankets peeling off satellites, for example," he said.
Their surveys are then used to help manoeuvre satellites through debris fields. Currently every one or two months a satellite is moved out of the path of floating space junk.
Another part of the
team's work involves making the space community more aware of how serious the
environmental problem really is.
"It's like waste management here on Earth. We come across waste dumped 15 years ago which people didn't know about," the researcher said.
According to Schildknecht, there is growing awareness among the space agencies, which have started to force commercial operators to stick to minimum guidelines. The ultimate goal is to come up with a code of conduct to limit the amount of debris created by space missions.
At certain altitudes – 800-1,000km – the problem is getting worse, he said, as there are lots of satellites and over time they may shed debris.
Most of this will gradually rain down and will end up in lower altitudes before entering the atmosphere.
"The major part of the problem is not the risk to Earth but to space missions themselves," he said.
But Lottie Williams from Tulsa, Oklahoma, probably wouldn't agree with Schildknecht.
Williams is on record as the first – and only – person to be hit by man-made space debris. On January 22, 1997, while walking in a park in Tulsa, she was hit on the shoulder by a 15cm piece of metal later confirmed to be part of the fuel tank of a Delta II rocket which had launched a US air force satellite in 1996. Fortunately Williams was not injured (Swiss Info, 2007).
Title: Growing Threat Of Space Debris
Date: December 23, 2011
Abstract: The space around Earth is a crowded space packed with nearly 22,000 spent rocket stages, dead or dying satellites and countless crumbs of human-made orbital flotsam. An average of one object has reentered Earth's atmosphere every day. Here are 10 of the most memorable manmade things that have rained down on us.
The U.S. Navy intercepted its defunct spy satellite USA-193 on Feb. 20, 2008, sending a trail of debris that some amateur astronomers reported falling over the northwestern United States and Canada. Department of Defense officials said they hadn't recovered any debris larger than a football.
A woman in Turley, Oklahoma, got a noggin-knock in January 1997 when she was struck with a lightweight fragment of charred woven material. She was not injured. The sky junk was identified as debris from a Delta 2 booster, which reentered the Earth's atmosphere on Jan. 22, 1997. Other debris from that booster included a steel propellant tank and a titanium pressure sphere.
Several mysterious spheres turned up in Australia in the 1960s, with some speculating these balls could be connected with UFO phenomenon. One such titanium sphere was spotted in Merkanooka, Western Australia. Dubbed the Merkanooka ball, the metal sphere was later identified as a tank used for drinking water in the Gemini V spacecraft, which was launched on Aug. 21, 1965, and reentered the atmosphere and splashed down into the Atlantic Ocean on Aug. 29 that year.
A secret Soviet-navy satellite called Cosmos 954, which was launched on Sept. 18, 1977, spiraled out of control. The spy radar antennas each sported a compact nuclear reactor, making the reentry one of the most frightening to date for people on the ground. On Jan. 24, 1978, Cosmos 954 reentered over Canada and shed debris across the frozen ground of the Canadian Arctic. Following the crash, the U.S. and Canada conducted overflights of the area and associated cleanup efforts.
On Jan. 21, 2001, a Delta 2 third stage, known as a PAM-D (Payload Assist Module-Delta), reentered the atmosphere over the Middle East. Its titanium motor casing, weighing about 154 pounds (70 kilograms), slammed down in Saudi Arabia, while a titanium pressurant tank landed near Seguin, Texas, and the main propellant tank plunked down near Georgetown, Texas.
Spare Space Parts
In May 1966, spacecraft debris was spotted in the Rio Negro District of Brazil. The metal parts were identified as coming from a stage of the Saturn development test (SA-5) that launched in 1964 and which reentered the atmosphere on April 30, 1966. The litter included a piece of lightweight metal, an oval-shaped chunk of metal, a black beehive-shaped structure and four pieces of fragile wire.
On Feb. 1, 2003, during its return to Earth, Space Shuttle Columbia disintegrated on reentry, killing seven astronauts. The catastrophic, lethal accident shed thousands of pieces of debris across a 28,000 square mile (72,520 square kilometers) area in eastern Texas and western Louisiana. More than 80,000 recovered pieces were stored for follow-up research.
After completing 51,658 orbits around Earth, the Compton Gamma Ray Observatory was intentionally deorbited due to a crippled gyroscope on June 4, 2000. As the spacecraft tumbled through Earth's atmosphere, its solar panels and antennas were thought to pop off first, while other parts likely melted. About 13,227 pounds (6,000 kilograms) of debris from the observatory splashed down into the Pacific Ocean southeast of Hawaii.
In the world of space litter, the heavyweight champ would have to be Mir, heftier in its day than any object (except the moon) to orbit Earth. The 15-year-old Russian space station began its suicidal nosedive on March 23, 2001, as it reentered Earth's atmosphere above the Pacific Ocean near Fiji. Though most of the station, weighing 286,600 pounds (130,000 kilograms), burned up in the atmosphere, about 1,500 fragments reached Earth's surface. Beachgoers in Nadi, Fiji, snapped photos of blazing bits of Mir debris and there were reports of sonic booms caused by heavy debris.
Weighing in at 77 tons (70,000 kilograms), the first and only solely-U.S. space station Skylab launched into orbit on May 14, 1973. Its orbiting operations came to a premature end on July 11, 1979, when Skylab plummeted through the atmosphere, sending chunks of debris raining down over an area stretching from the Southeastern Indian Ocean across a sparsely populated section of Western Australia (Space.com, 2011).
Title: "Space Junk 3D" Launches In Theaters As Russian Satellite
Plummets To Earth
Date: January 4, 2012
Source: PR Newswire
Abstract: Just as the crippled Russian satellite, Phobos-Grunt, threatens to fall from our sky, the film "Space Junk 3D" will open in IMAX® and other giant screen theaters in both 2D and 3D, beginning January 13th. The movie is the first to explore the exponentially expanding ring of manmade debris that threatens the safety of our planet's orbits.
"After half a century of space exploration we're now suddenly faced with what has long been a staple of science fiction—an orbiting junkyard of cast-off space debris," explains Academy Award® Nominee Tom Wilkinson, who narrates the film.
Harnessing the magical imagery of 3D Giant Screen, Full Dome and Digital Cinema. Director Melissa Butts takes us soaring in "Space Junk 3D"—from the stunning depths of Meteor Crater to an unprecedented view of our increasingly crowded orbits, 22,000 miles above earth.
View the trailer and check theater locations: Here
On-screen, Don Kessler, (ret.) Head of NASA's Orbital Debris Office and the "Father of Space Junk," reaches back to the beginning of our solar system for understanding and guides us through the challenges we face in protecting our orbits for the future.
"It isn't a coincidence that media headlines of falling debris are growing just as we launch this film," explains Kessler. "As we started researching this story we found that most scientists agree we've reached this tipping point where orbital debris will continue to grow exponentially if we don't address the problem."
At risk is the future of space exploration and the safety of the extensive satellite network that powers our modern day communication systems. This visually explosive journey of discovery weighs the solutions aimed at restoring Earth's orbits. Fueling this story are stunning time lapse sequences and dynamic images that transport the viewer by wrapping us in star fields and allowing us to witness massive collisions in space—both natural and man-made.
"We set out to tell this story with scientific accuracy utilizing mind-blowing immersive space visualizations," explains Butts. To accomplish this her team worked with the National Center for Supercomputing Applications (NCSA) to create breathtaking, state-of-the-art, 3D visualizations from scientific data.
Butts also consulted with NASA's Orbital Debris Program on content for the film, which will be shown in science centers around the world.
The film will have its Washington D.C. debut at the Environmental Film Festival in the Nation's Capital, where it will be screened in the Smithsonian Institute's National Museum for Natural History, this coming March.
View the Behind the Scenes Mini Doc: Here
"Space Junk 3D" is presented by Melrae Pictures, in association with Red Barn Productions. Produced by Melissa Butts andKimberly Rowe. Written by Shane Colton and Michael Benson. Lead Visual Effects by Luke Ployhar. Original music by Tom Hambleton, CAS. Director of Photography: Reed Smoot, ASC. Distributed globally by K2 Communications, the 38-minute film is available in both 3D and 2D, for Giant Screen and Digital Theaters (PR Newswire, 2012).
Title: Mishaps Bring Space Junk Problem Into
Date: January 13, 2012
Abstract: The news that a failed Russian Mars probe will come crashing back to Earth in the next few days reinforces a growing public perception that the sky is falling — that huge pieces of space junk could rain down on us at any moment.
Russian officials estimate that the 14.5-ton Phobos-Grunt spacecraft, which became stuck in Earth orbit shortly after its Nov. 8 launch, will re-enter the atmosphere sometime between Saturday and Monday. It will be the third uncontrolled satellite re-entry in four months, following NASA's defunct UARS craft in September and the dead German ROSAT satellite in October.
These high-profile events have helped put space junk on the map for many people who had never worried about the possibility, however remote, of getting conked on the head by a satellite shard. For example, insurance giant State Farm saw fit to address the issue just ahead of the UARS crash.
"While claims are handled on a case-by-case basis, you might be surprised to learn damage from satellite debris, aka space junk, likely would be covered under most insurance policies," the company wrote in a blog post Sept. 22, just two days before UARS came down.
Another major company, Farmers Insurance, aired a commercial during this winter's college football bowl games offering similar assurances to its current and potential customers.
And a new IMAX film called " Space Junk 3D " is felicitously timed to hit theaters Friday. The movie aims to raise awareness of the threat that orbital debris poses to space exploration and satellite communications.
A huge cloud of
Since the dawn of the space age in 1957, humanity has managed to clutter up near-Earth space with a staggering amount of junk. Much of it is defunct satellites, old rocket bodies and the shrapnel spawned when these objects collide.
NASA estimates that our planet's orbital debris cloud contains more than 500,000 pieces larger than a marble and more than 20,000 at least as big as a softball. The United States' Space Surveillance Network is tracking the softball-size objects to try to prevent collisions.
Despite the fevered media response to dramatic events like the UARS crash, space junk poses little threat to people on the ground. Most pieces of falling satellites burn up the atmosphere, and the bits that make it through are likely to land harmlessly in the ocean or on uninhabited land. To date, nobody is known to have been injured by a chunk of falling debris.
But that's not to say space debris is innocuous. It poses a real threat to the craft that orbit and observe our planet and provide navigation and telecommunications services. In 2009, for example, the Iridium 33 communications satellite was destroyed when it slammed into a defunct Russian satellite.
And space junk can endanger astronauts circling Earth. In June 2011, the possibility of a collision between debris and the International Space Station forced the crew of the orbiting lab to take shelter in a docked Soyuz vehicle, in case they needed to make a speedy getaway. The debris did not end up hitting the station.
Such incidents notwithstanding, Earth's debris cloud is not yet thick enough to seriously affect manned or robotic space operations, NASA officials say.
"It's really not too bad right now," said Nick Johnson, chief scientist of NASA's Orbital Debris Program Office at the Johnson Space Center in Houston. "We're not losing spacecraft right and left due to debris. But later in the century, the situation is going to be noticeably different if we don't do something different."
Johnson said humanity probably will have to come up with some effective ways to clean up the junk clogging Earth orbit. The good news is that we have time to figure something out, because the rate of debris accumulation is projected to remain quite low for decades to come.
"There is no urgency, thankfully. We can easily wait 10 or 15 years before we start doing anything," Johnson told Space.com. "We have time to go do this right."
Taking the problem
Another piece of good news, Johnson said, is that the orbital-debris threat, long recognized by those in the space community, has finally made it onto the radar of decision-makers in the United States and abroad.
Three events in recent years really brought the issue to the awareness of U.S. political and military leaders, according to Brian Weeden, a technical adviser with the Secure World Foundation and a former orbital analyst with the Air Force.
The first was a Chinese anti-satellite test in 2007, which added about 3,000 new pieces of space junk to the orbiting population. The second came in 2008, when the U.S. destroyed its malfunctioning spy satellite USA-193 in a manner that did not create a huge cloud of long-lasting debris. And the third was the Iridium 33 collision.
"It was those three things that kind of woke us up," Weeden told Space.com. The top brass have begun coming to grips with the fact that space is a busy and congested place, with many stakeholders around the world, he said.
"You have a situation where you have many people using something, and you have to figure out how you're going to use it in a sustainable manner for the long term," Weeden said. "And that's what everybody's working on right now" (MSNBC, 2012).
Title: Swiss “Janitor Satellite” To Clean Up Space
Date: February 15, 2012
Source: Swiss Info
Abstract: Swiss scientists plan to launch a mini satellite fitted with jellyfish-like tentacles that can clear some of the huge amount of debris orbiting above our heads.
Researchers at the Federal Institute of Technology, Lausanne, (EPFL), hope the SFr10-million ($11-million) CleanSpace One prototype satellite will be in the skies by 2016 in a bid to help resolve the worsening space junk problem.
“It’s time to do
something to reduce the amount of debris floating around in space,” Swiss
astronaut and EPFL professor Claude Nicollier told reporters in Lausanne on
After two years of research scientists working on the CleanSpace One project aim to build the first prototype in a family of clean-up satellites.
Their initial space mission will be to target and de-orbit one of two Swiss satellites – the SwissCube or the TIsat, launched in 2009 and 2010, respectively.
A number of other organisations, including the German, Russian and European space agencies and Nasa, are also working on this international space debris problem but the Swiss hope to be the first to become operational.
However, many challenges lie ahead.
The first involves propulsion. Once launched into space the 30cm-by-10cm-by-10
cm “janitor” will have to adjust its trajectory to precisely line up with the
target’s orbit using a new ultra‐compact
motor being developed at the EPFL.
Then when it approaches one of the junk satellites – travelling at 28,000 km/h, 600‐700 km above the Earth’s surface – CleanSpace One will then have to grab and stabilise it.
Inspired by the animal and plant world, the team plans to develop a tentacle-like gripping mechanism to help it hold on to the spinning object.
“Nature has a way of being very energy efficient. If you think of the jellyfish or anemone they can catch objects of different shapes which are tumbling or passing by. We will use them as examples,” Muriel Richard, deputy director of the Swiss Space Center, told swissinfo.ch.
Finally, once the janitor has secured the piece of junk, it will “de-orbit” the redundant satellite by firing up its engines so that both fall back together into the Earth’s atmosphere, burning up on re‐entry.
Not a One-Off
From launch to destruction the whole process should take six months.
Although the prototype will be destroyed on its first mission, the CleanSpace
One project is not a one-off.
“We want to offer and sell a whole family of ready‐made systems, designed as sustainably as possible, that are able to de-orbit several different kinds of satellites,” explained Swiss Space Center Director Volker Gass.
“Space agencies are increasingly finding it necessary to take into consideration and prepare for the elimination of the stuff they’re sending into space. We want to be the pioneers in this area.”
The international space community agrees that the space junk problem has become critical.
Since Sputnik 1 was launched in 1957, there have reportedly been 4,700 launches which have put 6,000 satellites into orbit. But only 800 are still thought to be operational, 200 have exploded in orbit and every year 100 new satellites are put up in space.
“When you are up in space you are initially struck by its beauty and spotlessness, but this first impression is misleading,” said Nicollier.
In fact, over 600,000 pieces of space litter are currently orbiting the Earth, mostly at an altitude of 300-900 kilometres. The debris includes parts of jettisoned rocket stages, abandoned satellites, solar cells, paint flakes and solid fuel.
“Most debris comes from satellites that are no longer in use – typically they have run out of energy and their solar panels or batteries don’t work; when they collide it creates lots of debris,” said Nicollier.
Space scientists agree that the major risk is not to humans on Earth, as most debris burns up on re-entry, but to space missions and satellites.
All but 16,000 objects in this huge field of space junk are smaller than a tennis ball. But with debris zipping around the globe at breath-taking speeds of up to 35,000km/h, collisions with satellites and other spacecraft – even involving small pieces – can be dramatic and generate huge costs for operators and insurance companies.
“If you look at the sheer amount of uncontrollable debris it’ll grow exponentially. If we don’t do anything now we won’t be able to put satellites in orbit for meteorology, GPS or telecommunication purposes,” EPFL scientist Anton Ivanov told swissinfo.ch.
In 2006 Nasa, which is monitoring the larger debris, released a study showing that a critical space junk tipping point was approaching. It is agreed that five to 15 pieces of large debris have to be removed annually starting in 2020 to prevent the situation from spinning out of control (Swiss Info, 2012).
Title: Astronauts Scramble For Escape Pods As Space Junk Threat Gets Serious
Date: March 24, 2012
Abstract: The six earthlings – three Russians, two Americans, and a Dutchman – aboard the International Space Station were stirred from their slumber Saturday morning to jump into emergency escape pods, once again drawing into focus the growing dangers of hurtling space junk.
The astronauts, orbiting 200 miles above the planet, were told by ground control to scramble into two docked Soyuz spacecrafts in case a piece of a wrecked Russian satellite should smash into the ISS, which could have heavily damaged the platform as both objects were traveling at orbital speeds – 17,500 miles per hour. The emergency was called off after the chunk passed by at an approximate distance of nine miles – which in space terms is a near-miss.
"Everything went by the book and as expected, the small piece of cosmos satellite debris passed the international space station without incident,” said a NASA spokesman.
Ground controllers did not believe the ISS was in extreme danger, but ordered the emergency maneuver after determining that the trajectories could intersect.
NASA says there are about 22,000 pieces of sizable space junk – primarily bits of old satellites – orbiting the earth and has in the past ordered the ISS crew to adjust the craft's path to avoid collisions. In all, NASA tracks nearly half a million pieces of space junk.
The piece that threatened the ISS Saturday morning came from the 2009 collision of the Iridium communications satellite and the Russian Cosmos 2251.
NASA spotted the latest threat too late for the crew to move the ISS safely out of the way. It was the third time in 12 years that astronauts were ordered to scramble for safety. Last June, a piece of debris came within 1,100 feet of the craft.
NASA said it followed a “precautionary and conservative” approach by ordering the astronauts to enter the escape pods. The astronauts – Russians Anton Shkaplerov, Anatoly Ivanishin, and Oleg Kononenko, Americans Dan Pettit and Dan Burbank, and Dutchman Andre Kuipers – were awakened about an hour early on what was to have been their day off to get into the Soyuz' crafts and close the hatches.
The spacefarers watched through the portholes to see if they could catch a glimpse of the zooming debris. "Nichevo ... Nothing," one of the Russian cosmonauts said.
If the 450-ton ISS had been hit and disabled, the astronauts were prepared to detach and descend back to earth in the capsules. Instead, they climbed back into the ISS and “resumed a normal and relaxing weekend,” NASA spokesman Rob Navias told MSNBC.
In response to concerns from the National Research Council that space junk is posing an increased threat to the earth's critical satellite network and the ISS, spacefaring nations have signed compacts to adopt best practices to better control expired space craft and their inevitable return to earth. About one large piece of space junk falls to earth each year. Just this week, villagers in Siberia reported a large “UFO fragment” falling to earth, even as space experts struggled to confirm its origin.
Researchers are also working on ways to corral space junk while in orbit. One idea, in theory, resembles a sort of space shrimp boat that would use a net to trawl for debris. Other ideas include using lasers to obliterate the pieces, and a Swiss company last month said they are developing a sort of “janitor satellite” to clean up the trash strewn skies (CSMonitor, 2012).
Title: Debris Prompts Space Station Crew To Seek Shelter
Date: March 24, 2012
Abstract: A passing piece of potentially dangerous space debris forced astronauts at the International Space Station to temporarily seek refuge in escape ships early on Saturday, U.S. officials said.
The debris, a fragment from an old Russian satellite named Cosmos 2251 that smashed into an Iridium Communications spacecraft in 2009, passed harmlessly by the $100 billion orbital outpost at 2:38 a.m. EDT (0638 GMT), NASA said.
With enough advance notice, NASA will maneuver the space station, which orbits about 240 miles above the planet, to put more space between it and passing debris. The other option is for the station's six crew members to shelter inside the two Soyuz capsules berthed at the station in case the outpost is struck and depressurizes.
"This was a very erratic piece of Cosmos 2251 debris and tracking it was very difficult," NASA spokesman Michael Curie wrote in an email to Reuters.
"Its size and exact distance are unknown, and the crew sheltered in place as a highly-conservative, cautionary measure. The predicted miss distance prior to its passing was 11 to 14 kilometers (6.8 to 8.7 miles) in overall miss distance. But again, we do not know its exact distance at 2:38 am EDT, the time of closest approach," he said.
It was the third time a crew has had to shelter in Soyuz spacecraft when debris was predicted to pass close to the space station, NASA said.
More than 20,000 pieces of man-made debris larger than a softball currently orbit Earth. Space junk travels at speeds of up to 17,500 mph, so even small pieces have enough energy to cause significant damage upon impact.
NASA says the greatest risk from debris comes from untrackable objects. The February 10, 2009, collision of the Russian and Iridium satellites added more than 2,000 pieces of trackable debris to the growing list of space junk. Two years earlier, China intentionally destroyed one of its defunct weather satellites to test a missile, generating more than 3,000 pieces of debris.
The U.S. military's Space Surveillance Network tracks objects as small as two inches in diameter in orbits close to Earth, such as where the space station flies, and about one yard (.9 meter) in orbit in higher orbits (Reuters, 2012).Title: Space Station To Move To Avoid Debris
Date: October 3, 2012
Source: MyFox DC
Abstract: The Russian space program's Mission Control Center says it will move the International Space Station into a different orbit to avoid possible collision with a fragment of debris.
Mission Control Center spokeswoman Nadyezhda Zavyalova said the Russian Zvevda module will fire booster rockets to carry out the operation Thursday at 07:22 a.m. Moscow time (0322 GMT).
The space station performs evasive maneuvers when the likelihood of a collision exceeds one in 10,000.
NASA estimates that more than 21,000 fragments of orbital debris larger than 10 centimeters (3.9 inches) are stuck in earth's orbit, and experts worry that orbiting junk is becoming a growing problem for the space industry.
There are six astronauts -- three Russians, two Americans and one from Japan -- onboard the orbiting laboratory (MyFox DC, 2012).
Title: Chinese Space Debris Hits Russian Satellite, Scientists Say
Date: March 10, 2013
Abstract: A piece of space debris left over from a 2007 Chinese missile test collided with a Russian satellite earlier this year, rendering the satellite unusable, a researcher said Saturday.
The collision appears to have happened January 22. That's when it's thought a piece of the Feng Yun 1C weather satellite, which was destroyed in the 2007 missile test, accidentally hit the Russian satellite, said T.S. Kelso, a senior research astrodynamicist at the Center for Space Standards & Innovation.
The collision changed the orientation and orbit of the Russian satellite, which was being used in scientific experiments, Kelso said. It may have also damaged it.
"There has been a piece of debris catalogued by U.S. Strategic Command as a result of that collision," Kelso said. "That would suggest that at least a part of the satellite broke off because of the collision."
It was February 4 when two scientists with the Institute for Precision Instrument Engineering in Moscow noticed a change in the orbit of the satellite, known as BLITS, Kelso said.
The scientists estimated the change happened January 22. They contacted Kelso because CSSI operates a service that looks for close satellite approaches, he said.
CSSI looked for objects that may have had a nearby approach with the BLITS satellite around the time of the collision. The Chinese debris was the only object they found.
Although the predicted distance between the debris and the satellite seemed to preclude a collision, the fact that the close approach happened within 10 seconds of the change in orbit made the Feng Yun 1C debris the likely culprit, Kelso wrote in a blog post.
CSSI is now working with the Russian scientists to find out more about the collision.
BLITS is a small glass sphere that reflected laser beams for research. Because of the collision, the satellite now faces the wrong way and can't be used, Kelso said.
The collision also sped up the satellite's spin period from 5.6 seconds to 2.1 seconds, Kelso said.
China launched the Feng Yun 1C polar orbit weather satellite in 1999. It was destroyed in 2007 when China targeted it for a test of a ground-based, medium-range ballistic missile.
U.S. tracking sensors determined the missile collision created hundreds of pieces of space debris, according to a U.S. official at the time. The test prompted formal protests from the United States and several U.S. allies including Canada and Australia.
The problem of collisions involving space debris is not a new one.
"Collisions happen all the time, everywhere. Big collisions -- now those are the rare ones," said space debris expert William Schonberg, chairman of the Civil, Architectural and Environmental Engineering Department at the Missouri University of Science and Technology.
The last major space debris collision was in 2009 between Iridium 33, an operational U.S. communications satellite, and Cosmos 2251, a decommissioned Russian satellite, Kelso said.
Scientists know of only a handful of such collisions, but that's only because they happened with objects that were being monitored. Kelso and Schonberg say it's likely there are other "junk to junk" collisions involving unmonitored objects that no one knows about.
In the case of the Russian satellite in January, "it would have been very difficult to tell there had been a collision if it hadn't been for the fact that somebody was operating the satellite and noticed a collision," said Kelso.
Experts and leading government agencies have been working on the space junk problem for decades, but it's a tricky one to solve, Schonberg told CNN.
Trying to catch or deflect debris runs the risk of making the problem worse, he said. The debris could shatter into more pieces or change orbit and be on a collision course with something else.
Some soft-impact lasers can nudge objects into a calculated orbit toward Earth so they will be pulled down and burn up in the atmosphere, Schonberg said. But scientists must make sure that happens over an ocean to minimize danger to people.
"Our technology has not caught up with our desire to clean up our mess" in space, Schonberg said.
"If nothing else," said Kelso, this collision "was a bit of a reminder that it will likely happen again, and maybe we should get back to work trying to figure out what to do about it" (CNN, 2013).