Last February 1, 2003, the world had witnessed the news that the space shuttle Columbia broke up upon its reentry on the surface of the Earth. There have been speculations about the real cause of the mishap, wherein one report states that there has been an error in the piloting of the reentry of the said space shuttle. In an article written by Jeffrey Kluger of TIME, scientists speculate that the probable cause of the breaking out of Columbia is because of the difficulty that the space shuttle had in reentering the Earth. The "sheer turbulence of re-entry" may be the cause of Columbia's fate (Kluger 2003 26). However, despite the possibility of this theory, one popular theory about this event is that there might have been a damage in the ship, wherein one of the heat-absorbing tiles in Columbia's external surface may have been damaged or broken. In support to this theory, Keith Phucas of the Time Herald reported that while in its orbit mission, Columbia was hit by "three pieces of insulation," whereby the theory that the Columbia mishap was caused by space debris collisions was formulated.
This information from various news sources shows how space debris collisions are significant in the said mishap last February. This recent event resulted to numerous questions that people wanted to be answered: What are space debris/junk? What are the causes of these materials in space? Its effects? How great is the impact of space debris to space exploration and its programs? Can this problem be remedied? These questions will be addressed in this paper, entitled: "The Problem of Space Debris and Junk: Causes and Effects." This paper will discuss background information about space debris, its causes and effects, and the methods, ways, and regulations that are made by space agencies and governments (concerned in space exploration) in order to prevent another space mishap from happening, as caused by space debris and junk.
What are space debris and junk?
Space debris and space junk are two different concepts, although both are hazardous to space programs and explorations. Space debris is a term appropriately suited to debris that are scattered around the Earth's orbit, which includes meteorites and other particles from the space. Space junk, on the other hand, are "bits and pieces of spacecraft" that were left behind after it exploded in space (Oliwenstein 1992 par. 1).
Space debris are generated by space collisions that happen in space. Examples of these space debris are fragments of space bodies such as asteroids, comets, and planets that are orbiting around the sun. Collisions usually happen in the Solar System; an example of one of the results of a massive collision between Earth and a space object had resulted to the formation of the Moon, which is actually a large mass fragment that was separated from the Earth upon collision. Space debris are hazardous and dangerous to man-made spacecrafts, since these space debris travel at high speeds and when they collide with a space body or object, the impact does not only generate a dent or damage to the body, but it might cause destruction for both bodies also.
Space junk, meanwhile, are objects that were left behind in space, and sometimes, artificial satellites and man-made shuttles that explode in space are left there to float and travel around the area of the Solar System. Space junks include small materials such as gloves and small parts made up of man-made materials. Phucas' article chronicled that in 1983, a chip of white paint collided with the window of the space shuttle Challenger, where the chip of paint had created a 4 millimeter crater, and the astronauts 'estimated' that the chip of paint (a space junk) was traveling at a rate of 10,800 mph when it collided with the window (Phucas 2003 pars. 1-3).
Effects and Threats of Space Debris and Junk
Space debris and junk can pose a tremendous danger to satellites and spacecrafts, whether these spacecrafts are manned or not. In a book entitled, "Orbital Debris," authored by the Commission on Engineering and Technical Systems, spacecrafts traveling in the lower Earth orbit, or LEO, are more susceptible to collide with smaller particles, with a one-millimeter diameter (CETS 1995 4). However, there is also a big chance that big-sized particles will collide with spacecrafts and satellites traveling along the LEO region. Collisions between spacecrafts and space junk usually happen in the LEO region because this particular region is highly-populated with space debris and junk. This is logical since most of the space programs and explorations that were conducted by nations on Earth are usually located in the nearest region away from the Earth, which is on the lower Earth orbit. Thus, because most of the satellites and spacecrafts in LEO are either damaged or had exploded before these structures return to Earth, these satellites and spacecrafts that exploded or were damaged were left in space. These materials therefore become space junk, and traverse along with other debris in space. Space junks become dangerous because they travel in space with great speed. Just like in the example cited earlier, a chip of white paint can create a substantial impact on an object it collides with because of its great speed. Hence, a space junk that is made up of metal and has a greater size will create a greater and more lethal impact than small space junk. Even greater threats are small junks that have collided with each other, creating a large mass of accumulated space junks in the process.
Space debris, meanwhile, are less frequent occurrences than space junks collision. However, they have an impact that is twice as great compared to space junks that collide with spacecraft and apparatuses. Debris impact is determined by the design of the spacecraft and/or the population of space debris a spacecraft is located. Space apparatuses located near highly-populated areas are more susceptible to collide with space debris, while spacecrafts with lower resistance and strength of its protective cover and outer layer have greater risk to be affected by space debris. It is important that in order to avoid these potential and possible problems in space, spacecrafts and apparatuses should be made with thick and strong protective outer layers so that when space debris inevitably collides with these man-made devices, there would be lesser impact and therefore, damage.
Technological Aspects of Resolving the Space Debris and Junk Problem
Scientists and astronomists have formulated possible solutions to solve the problem space debris and junk collisions. In 1996, there was a program formulated, entitled the "Mir Environmental Effects Payload" or MEEP, which aims to "study the impacts of space debris" (Watson 1996 par. 1). An apparatus will be attached to the Mir space shuttle, and for a four-year period, space debris, or more specifically, an orbit debris collector will collect any debris that collides with Mir. Upon returning to Earth, all space debris collected within that four-year period will be analyzed and studied in laboratories in Earth in order to determine its composition, and determine the "origins" of these debris (Watson 1996 par. 4).
Another technology that attempts to solve the problem of collisions in space is through the 'deorbiting' of space debris in space, so that spacecrafts won't collide with them. This report was made by a study called "Orion," wherein laser technology are used to detect even the smallest debris and "micro-meteorite" in space, which will enable scientists to "irradiate objects with a ground laser... ablate a surface layer of the debris and cause a plasma blowoff" (Bekey 1997). This 'blowoff' will result to the alteration of the object's orbit, thereby removing it from the path of a spacecraft or apparatus, and preventing a damaging collision from happening.
Legal Aspects of Solving the Space Debris and Junk Problem
The main problem that must be confronted in solving the space debris/junk problem is that space explorations and programs should leave lesser 'junk' as much as possible. However, this can't be prevented since some space explorations and programs do not become successful, and end up exploding while in space. However, studies have determined that nations conducting space explorations must be imposed with debris control laws. One important legal policy that is being implemented is the "law of salvage," wherein debris hat were scattered in space will be collected by nations, although this policy is restrictive because this policy is only possible for large debris and junk, thereby eliminating the clean-up of equally dangerous small debris in space (Collins 1992 par. 25-6).
Two important policies that have been implemented to solve this problem are the following: the Commercial Space Launch Act of 1984 and the Lund Remote Sensing Commercialization Act of 1984. The Commercial Space Launch Act of 1984 is formulated to establish "licensing process that addresses hazards from space debris generated by commercial launch activities," which includes satellite launches and other relevant commercial activities. These launches have left some debris or junk once…