Why You Should Care about Space Debris. (9 of 9)

Satellites are now vital to many aspects of scientific and technological exploration, along with the communicative and societal aspects, which is a far cry from the first satellite launch 45 years ago. But in addition to the expansion of satellites, there has also been an explosion in the amount of space debris, the creation of possibly hundreds of millions of pieces of human trash orbiting the Earth and putting those satellites and human space exploration at great risk because of the vast destructive nature of space collisions. This is a purely human-caused problem, but the people and counties that should be addressing and forming ways to alleviate it, do not and are not presently enough. They are, instead, pursuing courses that will only intensify the problem, and they do so because of the fact that many are not even aware of the fact of space debris, and fewer still are aware and are concerned about the ramifications of the sheer amount of garbage orbiting the Earth. But space debris exists and it is an issue that needs to be solved soon, before human civilization goes down a path that leads to the ruin of the future use of Earth’s orbits.

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I posted this on the internet not to show off on what a good job I did, but to be able to fulfill this essay's purpose, to convince people that they should be aware of space debris.

Space Law (8 of 9)

Space law is simply, the laws in space, as created by the UN Committee on the Peaceful Uses of Outer Space (COPUOS), but since space is a communally-owned territory, like Antarctica, they cannot be enforced readily. The current laws are worded vaguely and rather loosely, making them difficult, if possible, to enforce. The UN has no enforcement powers, so for its proposed laws to be passed, each country has to adopt it on its own, and since no country would agree to a resolution that would limit its decisions, the more loosely-worded a proposed law is, the more countries that would adopt it. But this is not to say that these laws are followed, even when they are passed. For example, in 1979, the United States’ Skylab crashed in Western Australia, scattering debris over hundreds of miles. There was in effect a liability law that the US and Australia had adopted that which allowed a suing for damages if harmed by a falling spacecraft to the country that launched the spacecraft. Australia could have sued the US, but only the Esperance Shire of Australia fined Government of the United States of America for the littering of Skylab, the old space station. But the US never paid. (Taggart, 2001)
ut this lack of care about the repercussions of space debris is not just in the past, but also fully in the present. In 2002, George W Bush withdrew the US from the1972 Anti-Ballistic Missile Treaty with the Soviet Union, which prohibited placing weapons in space, to develop the “Brilliant Pebbles” proposed missile defense program, which consists of space-based lasers and interceptor missiles. (Primack, 2002) This step of the United States government only leads the US and the world much closer to the weaponization of space, the deterioration of the currently very lackluster space laws and agreements, not to mention putting at risk the now common use of orbital space satellites in modern-day life.

The Weaponization of Space (7 of 9)

In early January 2007, China exploded one of their derelict weather satellites, the Fengyun- 1C, in orbit, using it to test their new anti-satellite weapons system. They sent a suicide-missile to smash into the forgotten satellite, creating an explosion and a massive cloud of debris. To current knowledge, it created approximately 2,600 pieces of trackable debris (>1.5 inches) and an estimated 150,000 fragments larger than .4 inches; a veritable destruction of space orbit, the worst breakup of recorded space use. (NASA, 2008). Before that incident, the major events that created space debris were due to old rocket bodies with unused fuel unpredictably exploding, months or years after they were abandoned in orbit. Before this event, the greatest event in terms of the amount of space debris created was in 1996, when a discarded American rocket engine exploded, creating 713 fragments. (Broad, 2007) While it is still a major problem that scientists should and are trying to alleviate, the threat of the weaponization of space is much more menacing to the future of space use.

he main problem is that most people see space battles with the “Star Wars effect” in mind, from the classic science fiction series released in the 1970s, in which the targeted object explodes into nothingness, the matter making it up dissipating, leaving empty space left behind. An unreal scenario. An explosion in space creates thousands of pieces of refuse blasting out in every direction, into every orbit, putting all of the other space vessels at risk for tens to hundreds of years in the future. Another problem of sending things into space is that they might stay up there for a long period of time depending on the orbit, with some orbits lasting forever, while some will renter very quickly. In low earth orbit, if an object’s orbit is at less than 124 miles (just under usable low earth altitude), the orbit will only last a few days until reentering the atmosphere, if it is between 124 and 373 miles, it will have an orbit of a few years until reentry, if 372 to 497 miles, a few decades, and if greater than 497 miles, than it will remain orbiting for centuries. (NASA, 2005) And while the fragments of the Fengyun-1C had every low earth altitude orbit, the majority was in the 466 to 621 mile range, which expects that most of the debris will remain in orbit for a very long time.
Afterwards, it was leaked that the Chinese scientists in charge of studying the effects of the anti-ballistic missile test on the Fengyun-1C predicted that the huge explosion would happen, with disastrous effects, but the persons in charge of the test didn’t seem to take this into account. But the only real repercussion for China due to the incident was to cancel a debris discussion with the UN that has been scheduled beforehand, out of embarrassment. But that is the problem with the current space laws; they are easily circumnavigated or forgotten if a particular county feels like it is reasonable, because most do not see debris as a real problem, and those that do are hindered by the laxness and lack of enforcement of the space laws.

How Space Debris is Currently Handled-part 2 (6 of 9)

The mitigation or the slowing of growth, of debris consists of limiting the debris released during normal operations, minimizing in-orbit break-ups and collisions and to seeking to dispose of the spacecraft after its useful lifetime, either by placing in an unused (graveyard) orbit or to de-orbit it, sending it back to Earth. (IADC, 2007) In 2004, The FCC required that to receive a FCC license and continue transmitting, all U.S.-licensed satellites launched after March 18, 2002, will have to be retired in a graveyard orbit after their useful lives (de Selding, 2004). While this is a commendable effort, it is a problem for most of the commercial satellite companies, because the amount of fuel to send the spacecraft into an unused orbit equals 3 months of normal use. And this also quite is difficult to enforce, because much of the time satellites malfunction of are stopped in some way from changing orbits. So while the current method for dealing with the space debris problem by mitigation and shielding seems to work, it cannot be maintained at current levels and keep space usable at current or increased loads in the future. For one of the major problems of space debris is that even if no more spacecraft are deployed and no more potential debris introduced, the amount of space debris would still increase, as proposed by the Kessler syndrome.
The Kessler syndrome, as discovered by Donald J Kessler, formerly head of the NASA orbital debris program office, posits that when the number of debris in orbit reach a critical mass, than it reaches a domino effect of destruction and debris called collisional cascading.
his is when the debris created from one collision or explosion spreads out and causes another collision which then creates more debris and so on, creating a steady growth of damaging space debris that greatly decreases the potential for orbital space use. This decrease of use would be due to the sheer amount of speeding, colliding debris that would destroy a spacecraft in a matter of months or days, or would require so much shielding that, except for the wealthiest of organizations, it would be economically impossible to launch spacecraft that size. Despite this worrying predicament, the required critical mass has been reached in most of the commonly used low earth orbits because of the almost unchecked growth of space debris, due to a lack of concern. The future of space use is too important to risk. The world has become so heavily dependent and benefited so much from artificial satellites in only 45 years, that allowing Earth’s orbit to become a debris cage for the Earth is a step backwards, away from the technological and space age. But it sometimes seems that the countries of the world are taking that step backwards by arranging to weaponize space.

How Space Debris is Currently Handled-part 1 (5 of 9)

The current policy of the US (and all other countries) is to not seek ways to get rid of debris, just to diminish the growth of it. The most recent statement, from the United States’ National Space Policy says,
"Orbital debris poses a risk to continued reliable use of space-based services and operations and to the safety of persons and property in space and on Earth. The United States shall seek to minimize the creation of orbital debris by government and non-government operations in space in order to preserve the space environment for future generations."(USNSP, 2006)

The existing management of the problem of space debris is a combination of monitoring the larger debris and shielding orbital spacecraft from the smaller debris. The monitoring is done by The US Space Surveillance Network with a combination of satellites and ground-based radars, tracking debris larger than 3.9 inches in low earth orbit (124 vertical miles to 1240 vertical miles), where the majority of the satellites are, and larger than 3 feet in geosynchronous orbit (22,236 vertical miles), where there are approximately 300 satellites. The debris is tracked every day to predict and prevent collisions with spacecraft. Satellites and The International Space Station can be maneuvered out of the way of larger pieces of debris if given sufficient time to plan and implement beforehand and shielding can protect the spacecraft from the smallest debris (<.4 inches), even though it cannot be tracked. But even the smallest debris can ruin some satellites. For example, a single-tether satellite was rendered useless by a small particle severing the tether, losing its most recent information payload and requiring immediate action to stabilize it. But the middle range from .4 inches to 3.9 inches is classified as the debris “threat”, since debris that size can smash a satellite into more useless and dangerous debris, but technology to shield against that size of debris isn’t practically or economically feasible for most spacecraft, and it is too small to allow radars and other observational equipment to track it.

Why are Satellites so Important?-part 2 (4 of 9)

Satellites are also used to observe space, to find out the mysteries, laws and events of the cosmos. Space is ideal for this because most of the emissions from space, x-ray, gamma and such, are blocked out by the Earth’s atmosphere. This atmospheric shield is perfect to sustain life, but becomes rather annoying when you want to know what goes on beyond Earth and in space. Figure 3 shows clearly the percentage of each electromagnetic wavelength that goes through the Earth’s atmosphere, and some of the satellites utilized to observe space on their differing wavelength frequencies. The far left represents gamma rays, x-rays and ultraviolet light. The rainbow on the left side represents the visible light spectrum, which is partially blocked by the atmosphere but is monitored by the Hubble and land-based telescopes. The middle is the infrared range. The right shows the only range that is let fully though, the mid-range radio waves, which are monitored on Earth. The chart clearly shows that the range of full and even partial clarity of wavelength is small, showing the necessity of space-observing satellites. With all of the additional wavelengths to study, it increases that many more chances to learn about the universe.
So if these satellites are becoming so increasingly important, is there so much space trash? The space age is only 45 years old, but already the 680.4 tons of space debris make placing anything in space hazardous, especially the more fragile elements of satellites. But if the larger fragments, if objects the size of a softball are considered large, can demolish a satellite with one errant twist in an orbit, why are the smaller fragments, from the .4 and 3.9 inch range, are the ones that are classified as threats by the debris scientists. The smaller debris are almost untrackable and can do considerable damage, because they cannot be detected but can still mutilate spacecraft. But even the tiniest debris, the paint chips the size of a fingernail, are hazardous, for they can form clouds of speeding fragments that can strip an object with the destructive force of a sandblaster, corrupting the satellite elements.

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Figure 3 was created by NASA and the European Space Agency (ESA)

Artifical Satellites and Orbital debris( 2 of 9)

Artificial satellites are used in almost every business or even for personal use. From satellite communications, earth science, astronomy, urban planning, to tracking packages and monitoring weather patterns and natural disasters, satellites are becoming increasingly essential to the modern way of business and life. For example, enhanced 911, in which the emergency station finds the location of the caller, depends upon GPS satellites for most mobile phones. And weather tracking and imaging, vital to air and water traffic and a great help to everyone else, is greatly dependent upon the images that weather satellites provide. So, far from abandoning space after the final moon landing in 1972, space use has only been expanded. In 2007 alone, there were 68 orbital launches and 22 spacewalks worldwide, 19 of those to maintenance artificial satellites. The US and the world have come to depend upon these orbiting satellites, necessitating the tracking and use of thousands of them.
Space debris is considered a problem because of the collisions between spacecraft, especially satellites, and debris. Figure 1 shows the distribution of observable debris (>3.9 inches) in Earth’s orbit, while Figure 2 shows the distribution of satellites in Earth’s orbit. This comparison shows the correlation between the most commonly used orbits and the amount of debris they possess. While spacecraft are made out of extremely durable material, the main problem lies in the large velocities that objects have in orbiting the earth. In space, a .4 inch aluminum sphere in an average orbital velocity of about 16.1 miles/sec has the equivalent velocity of a bowling ball moving at 300 miles/hour. (NASA, n.d.) So while a great deal of the mass of the satellite may be due to the shielding, it usually is not enough to protect against larger debris. And that debris has an especially dehabilitating effect on artificial satellites with their more delicate elements such as memory chips, solar cells and observational lenses that are easily corrupted. So a collision between debris and a satellite is always disastrous to both the information payload on the satellite and the usefulness of the satellite afterwards.


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Figure 1 is from the NASA Orbital Debris Program Office Education Package (2005)
Figure 2 is from NASA’s J-Track 3-D (November 16, 2008.) (please click to enlarge)

Why Should I Care About This Space Trash Problem, Anyway (1 of 9)

The Effect of the Uncontrolled Growth of Space Debris on the Current and
Future Space Use of Artificial Satellites


The space around Earth is empty, isn’t it? Just occupied by the moon, a few comets and satellites, right? But the earth’s orbit has over 680.4 tons (3 million kilograms) of space debris, unusable man-made material speeding in Earth’s orbits; space “junk” made up of not only items accidentally lost during space missions, such as a glove lost on the first American spacewalk, a camera lost near the spacecraft Gemini 10 and so forth, but also discarded rocket stages, dead satellites and other abandoned spacecraft that are beyond their usefulness but cannot be sent back to earth (Tufte, 1990). But much of the debris is made up of the shattered fragments of such deserted spacecraft, due to collisions with other debris or normal wear and tear of use. For example, all 31 of the nuclear-powered Radar Ocean Reconnaissance satellites (RORSATs), launched from 1967 to 1988 by the Soviet Union, still orbit the Earth unused, but, due to a construction error they create a much bigger problem. 16 of the satellites leak liquid sodium-potassium reactor coolant, making tens of thousands of coolant droplets speeding around after the abandoned satellites, making the orbit extremely hazardous to any human use. But while the RORSAT problem is unique, the fact of debris has become commonplace. After 45 years of space use, there are known to be 17,000 objects larger than 3.9 inches in orbit, which is confirmed by debris monitoring by the US and other countries. But the projected amount of objects between .4 and 3.9 inches in diameter is greater than 200,000, and the numbers of particles smaller than .4 inches, such as paint flakes and metal splinters, probably exceed 10,000,000. (Stansbury, 2005) This is in addition to thousands of orbital satellites that currently have considerable use.

Space Trash-an introduction

The next few posts will cover a research paper about orbital debris. Orbital debris or space trash is a problem that most people are not aware of and probably can not get good information about (I know I had difficulty at first), but this is assuming that they care about such problems. This paper is intended to produce well-researched information that will educate about the effects of orbital debris on communication satellites and countries' reaction to this growing problem. It is intended to convince that orbital debris is a relevant problem to our everyday lives, and we should have an opinion on it.

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