There have been many remakes of the Chicken Little story, but what they all have in common is that the little chicken truly believes that the sky is falling. Of course she was mistaken and the only thing that fell on her head was an acorn. It is a scientific fact that the sky cannot fall, but things in space can come crashing down to earth, which will make it seem like the sky is falling for those who lack intelligence. There are two types of objects that fall from space: natural occurring objects like comets and asteroids or human made objects like satellites and spaceships. For the past few decades humans have been sending satellites to space so they can study Earth. Naturally, man made objects, like the satellites, are not meant to last forever and they eventually stop working. After years of orbiting some of these dead satellites are reentering the Earth’s atmosphere and the media have been reporting the news of these falling or fallen satellites. Not only are falling satellites a threat to humans, debris just orbiting the earth can be harmful for working satellites and the astronauts. The space junk is already big, but when satellites collide into other satellites more debris is created, causing the space junk to grow even more.
All eyes were on the sky as major media outlets reported the descent of satellites falling from space orbit and reentering Earth’s atmosphere and ultimately crashing into parts of the Earth. NASA confirmed that the Upper Atmosphere Research Satellite, UARS, fell back to Earth on Saturday morning, September 24, 2011, (NASA). Even more recently, on October 20, 2011, the associated press confirmed that, “pieces of a retired German satellite hurtling toward the atmosphere may crash to earth this weekend …”(washington post). There are many more news reports like these all over the newspapers and TV, but aero.org has information on what satellites have fallen and when future ones will fall.
NASA and other programs create models to predict when the debris of satellites will fall and a general location of where it will fall. They even predict how much will burn up while reentering the Earth’s atmosphere and how much will survive. However, none of these predictions are exact and predictions can be changed many times until the satellite falls. The news agencies report about these satellites until they are done falling and when nothing newsworthy happens like someone getting hurt will go on to other news more noteworthy to them. Then the cycle will repeat when another satellite is supposed to reenter the Earth’s atmosphere.
Why exactly do satellites come back to earth? From a scientific perception, aerospace website explains:
“Objects in orbit are exposed to atmospheric drag, just as aircraft and automobiles are near the ground. In space, of course, the atmospheric drag is much less than that experienced closer to the ground but, over time, even a small amount of drag can result in a satellite’s reentry into the denser atmosphere.
Objects orbiting at low altitudes may be removed from orbit by atmospheric drag within weeks, months, or years depending on the object and its altitude. Objects at higher altitudes may remain in orbit for hundreds or thousand of years” (aero).
In simpler terms, the gravity pulls on the satellite and it gets dragged into the Earth’s atmosphere causing it to crash back to land. This is why objects that orbit the Earth will not stay in space forever.
The likelihood of more debris falling out of orbit is a real threat. Humans have been in such a hurry to put material into space that a tipping point will soon be reached. Earth’s orbit is littered with scientific, military and commercial satellites to such a degree that it is impossible to track all the space junk. Tracking is important to keep astronauts and working satellites safe, as well as monitor the instances when a satellite falls back to Earth to adequately warn inhabitants upon which it may fall. Also more debris is created when satellites crash into each other and the pieces break off creating smaller debris. Space junk will just continue to grow until a solution can be discovered to lessen debris in space, and therefore lessening falling debris.
Without an effort to find a solution to space junk, further exploration and use of the space around our planet could become impossible and the likelihood of major damage and death to life on our planet could become a harsh reality. There will be news reports of people being impaled with space debris and then the news will have something noteworthy to report. Sad, but it is true. The good news is that scientists have been studying the problem of space garbage for many years, and solutions are being worked on to clear space of junk and keep the planet safe from fall out. There is not however an easy solution to the problem, nor a one-size-fits-all solution.
Our planet Earth is now encircled by a human-made asteroid belt. As more activity and collisions occur, the belt gets tighter and thicker. Some scientists believe that Earth’s belt is at risk if the problem is not addressed soon. In these difficult economic times, it is difficult to imagine governments or corporations spending great sums of money to research and develop the projects that will lead to a solution to space junk; however, if this is not done, we may be unable to explore and use the next frontier which is space. In the children’s story of Chicken Little the animals were afraid when they thought the sky was falling; today, in real life, while the sky is not falling there are objects that we put there that are falling, and it is time that we acted to clean up the mess before something tragic occurs. It would be a shame if our legacy to the future was self-imposed imprisonment on a planet raining space garbage from the sky.
-GW