Wednesday, May 14, 2008

Space Ecology:
The Final Frontier of Environmentalism

By Lynda Williams
Published in Natural Living Magazine


The space age began 50 years ago with the launch of Sputnik by the Soviet Union. Since then the world has come to enjoy and depend upon space technologies including satellite communications, earth observation and early warning systems, search and rescue, traffic and resource management, GPS, global security and entertainment. However, like so many other environments humans exploit, space has become so trashed with space junk that it is at risk of becoming too polluted to use.



The U.S. Space Surveillance Network (SSN tracks over 12,000 objects in orbit larger than an apple (5 cm), including 850 active satellites. Space debris– dead satellites, exploded rockets, nuts, bolts and other pieces of junk – travel at over 7 km/s in crowded regions of space where satellites operate. A collision with debris 1cm or larger can seriously damage or even destroy a satellite. A collision with a chunk of junk larger than a grapefruit (10 cm) could not only destroy the satellite, but also create large amounts of additional debris, creating a chain reaction of collisions between satellites and debris, making the orbit unusable for years and possibly decades. 

 Although the risk of such a catastrophic collision is relatively low, as human activity in  space increases in the coming years, the risks will also increase. Collisions between defunct satellites and debris have been observed and some mysterious breakups and explosions may have been due to collisions with debris too small to track. In February of 2007, the ‘Breeze-M’ upper stage of a Russian Proton Rocket mysteriously exploded over Australia, littering space with more than 1000 pieces of junk.  In the same month, a retired China-Brazil spacecraft mysteriously broke into dozens of pieces, possibly due to a collision with space debris. 

 Worldwide, 50-100 new satellites are launched every year, all of which produce space debris. Missions to the moon and beyond by the US, Russia, and China promise to increase space traffic and trash. Missile defense and anti-satellite testing has the greatest potential of trashing space. Detonating a nuclear weapon in low earth orbit would destroy all the satellites in the orbit. The booming space tourism industry, spurred on by X-Prize incentives, NASA design contests and lax government regulations will increase the number of launches and amount of space litter. Space-based geo-engineering schemes to combat global warming are being studied, which would invariably contribute to the space debris problem. Ironically, if space becomes sufficiently trashed, the reflection of sunlight by the junk could possibly have a net cooling effect on the Earth and solve the global warming problem!

 Even if no further space junk is put into space, the existing debris will break up in time and dangerously increase the amount of trash. A piece of space debris can have an orbital lifetime of days to hundreds of years depending on its size and altitude.  There are currently no means to remove or mitigate space waste, though schemes for ‘space garbage ships’ are being studied. The costs for such programs are astronomical and, ultimately, would be paid for by taxpayers.

 People on the ground are already paying for the legacy of our space age with their health. Ammonium perchlorate, a toxic ingredient of solid rocket propellant is increasingly being discovered in soil and water throughout the country.  Recent studies by the Center for Disease Control and Prevention have shown detectable levels of perchlorate in all adults tested, and higher levels in children and in breast milk. Perchlorate decreases thyroid hormone levels and can affect the brain development of fetuses.  The EPA are balking at plans to set a national cleanup standard for perchlorate. 

Kazakhstan has the unfortunate luck to be directly under the flight path for Russian Proton Rockets which have on several occasions exploded over their countryside.  In September of 2007 a Proton Rocket exploded two minutes after takeoff, showering central Kazakhstan with debris and toxic heptyl rocket fuel, rendering thousands of acres of farmland useless for agriculture. Contact or digestion of heptyl rocket fuel can kill a person. Authorities have blocked access to the land to farmers and shepherds. The village of Ploskoye, in Siberia, is also under the flight path of Russian launch vehicles. When the first stage of the rockets separates, a large amount of unused rocket fuel explodes and rains down on the village. Ploskoye and its neighbors report cancer rates 15 times higher than the national average.

 There are 32 defunct nuclear reactors circling the Earth. In total, about a ton of radioactive fuel is orbiting the Earth. In order to prevent radioactive material from re-entering the Earth’s atmosphere and endangering life on the planet, most of the nuclear satellites were moved into higher orbits where they will remain for hundreds of years. Although no nuclear-powered satellites have been launched into Earth orbit since 1988, nuclear propulsion is being considered for spacecraft for long missions to other planets which may increase the amount of radioactive debris in space. In 1978 the Soviet satellite Cosmos 954 disintegrated over Canada, scattering across a vast area thousands of radioactive pieces of radioactive debris.


There is also a hazardous risk on the ground from satellites and space debris that re-enter the atmosphere and do not burn up completely during reentry and land on Earth. Some satellites may be navigated into a ‘safe’ landing in an uninhabited region of an ocean but most often the satellite randomly renters the atmosphere and it very difficult to predict where it will hit Earth. Although nobody has been killed by falling space debris, as the number of intended reentry events and accidents increase, so will the risk. “Of course,” says Ken Hodgkins, of the office of Space and Advanced Technology at the US State Department , “the probability of real damage being caused is low, but if something does happen, the consequences could be catastrophic for everybody.” 
Air traffic is also a possible target for space rashing hurling though space. In March of 2007  pieces of space junk from a Russian satellite coming out of orbit narrowly missed hitting a jetliner over the Pacific Ocean. A pilot of a Lan Chile Airbus A340, which was travelling between Santiago, Chile, and Auckland, New Zealand, notified air traffic controllers at Auckland Oceanic Centre after seeing flaming space junk hurtling across the sky just five nautical miles in front of and behind his plane.

 The greatest threat to the space environment is the testing and deployment of missile defense and anti-satellite (ASAT) weapons. In January of 2007 China launched a ground-based missile into space and blew up one of its defunct
weather satellites, producing over  2,000 pieces of debris larger than 5 cm, thereby increasing the total amount of  space trash in low Earth orbit by 20% in the worst space debris incident ever. The single explosion increased the risk of debris collision by over 15%.  Currently, there are no international laws restricting the testing of ground based anti-satellite systems. Anyone can blow up their own satellite in space without any legal ramifications.  Traffic in space is getting so congested with space trash that satellites must be periodically nudged in their orbits in order to avoid collisions with debris. More likely, predictions made by space monitoring systems are not accurate enough for any action to be taken by satellite operators: an adjustment might inadvertently place an endangered satellite directly into the path of an oncoming piece of junk, rather than away from it. According to John Campbell, a VP of Iridium Satellite, “We grit our teeth and hold our breath; that’s our action.” 

Space industry folks have been keeping faith in the “Big Sky Theory” of aviation, namely, that space is so big that the risk of collision is insignificant. But this theory, like the “Big Ocean” and “Big Atmosphere” versions that came before it, is clearly growing defunct as space fills up with trash. Industry has been free of space debris regulations, primarily because it is in their best interest to keep space clean so they can continue to do business in it. However, with China’s ASAT test and the recent rocket breakups, private sector space experts are realizing that space trash is becoming a serious liability to space assets and that something needs to be done about it on an international scale.

 Some progress towards regulating space debris is being made both on a national and international scale. The US has implemented policies and practices for debris mitigation in the form of NASA and DOD policy statements. The FAA and FCC require that licensees demonstrate plans for space debris mitigation and end-of-life disposal of satellites so you can’t get permission to launch a satellite unless you can show that you will remove your satellite from space at the end of its life. This usually entails moving the satellite into a lower orbit where it will eventually re-enter the earth’s atmosphere and be destroyed either by burning up or crashing to Earth within 25 years of deactivation. But changing the orbit of a satellite requires fuel to carry out the maneuver, which increases the payload weight and thereby increasing launch costs significantly. Private industry has been reluctant in the past to cover these costs because they claim it makes an unfair playing field with foreign competitors who do no have to abide by such regulations. 

In 1967 the UN Committee on the Peaceful Uses of Outer Space (COPUOS) negotiated the Outer Space Treaty (OST) which promotes peaceful uses of outer and the prevention of "a new form of colonial competition” in space.  It also prohibits putting in orbit around the Earth, or on the moon or any other celestial body, nuclear or any other weapons of mass destruction. Not included in the treaty are restrictions for anti-satellite weapons. States are ultimately responsible and liable for any damage caused by any entity, whether it is governmental or private. Recently the general assembly of the UN adopted CUPUOS guidelines on space debris mitigation, which are largely based on US policy, although they are non-binding and unenforceable. Hence, China has suffered no legal ramifications from trashing space with its ASAT test, although the political fall out from the test has been severe.  Interestingly, the NY Times reported that the Bush Administration knew about the test before hand but didn’t take any actions to negotiate with China to stop it.  

International laws, which are binding and enforceable, are needed in order to guarantee that all space faring nations follow good environmental practices in space. The Outer Space Treaty must be strengthened so that it prohibits anti-satellite weapons on the ground or in space. International negotiations are needed to halt an already looming arms race in space.  Over the past decade many countries, including the US, have thwarted efforts to begin negotiations to ban a weapons race in space. According to David Wright, co-director of the Global Security Program at the Union of Concerned Scientists, “the US should be promoting negotiations to protect our future in space as well as security on Earth.” 

It is time for all the passengers on space ship Earth to embrace an ethic of space ecology, now, before space becomes too trashed for us to reach the final frontier of our dreams. 









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