Season 4, Episode 6: Race Fever
David and Mayko travel to Quebec to investigate a mysterious illness among cyclists competing in a tour, who have been stricken with a respiratory infection of unknown origin. Air particle analysis indicates the presence of forty-year-old aluminum chloride, radioactive materials, and carbon isotope concentrations not found on Earth. NASA confirms that a satellite had crashed near the race site at a time that coincides with the onset of the unexplained illness.
The sky is falling
When an acorn fell from a tree and hit Chicken Little on the head, he mistakenly thought the sky was falling and began his fabled quest to tell the king this troublesome news. Chicken Little’s fear that the sky is falling might actually come true outside of the fictitious world, indeed even on Earth; however, rather than the sky actually falling, it would be more appropriate for him to have said that there is ‘junk falling from space.’
The Soviet Union launched the first satellite, Sputnik, in 1957. Today, there are approximately 2500 satellites orbiting the Earth with an average of 20 additional satellites entering space each year. That’s a lot of equipment floating around up there, and as the old adage says, what goes up must come down.
Space debris – often referred to as “space junk” – consists of man-made objects that used to serve a purpose but now just aimlessly orbit the Earth. This space litter re-enters the Earth’s atmosphere on a regular basis – most of the time we don’t even notice. But sometimes it can be problematic. In February 2008, the United States shot down an orbiting, non-functional spy satellite because of the risk that it might spread toxic substances upon re-entry. Blowing up the satellite into many pieces made the size of the debris small enough that it would all burn up in the earth’s atmosphere before it could reach the Earth’s surface.
Imprecise science?
As discussed in the Facts Behind the Fiction, space debris is carefully tracked to make it possible for people to intervene if and when a piece poses a threat to the Earth or its inhabitants. However, monitoring space debris is an imprecise science and at best can provide a time window for likely re-entry and a large geographical area of potential impact of those objects large enough not to burn up in the atmosphere.
Yet, the odds of being affected by falling space debris are extremely low. To date, there are no known cases of people being hit and injured by falling space debris, which is not too surprising - since so much of the Earth is covered by water, there is only about a 25% chance that the debris would fall on land, and even if it did, much of the land is uninhabited…by people, anyway.
But let's not forget about the many other plants and animals on land. Nor should we forget that our lakes and oceans contain many organisms and vital ecosystems that we want to protect as much as those on land. So, the current inability to precisely predict impact time and location makes it difficult to eliminate all potential harm to organisms on Earth from things falling from space. With this in mind, perhaps we should weigh all the probable risks and benefits before sending potentially hazardous materials into space.
Why is space junk there anyway?
So if space junk can cause harm to humans or the environment when it returns to Earth, why do we continue to send up potentially hazardous objects? In weighing the potential risks and benefits, it would certainly appear that the benefits greatly outweigh the small risk of harm to us or any other living things from space debris.
What benefits? There are numerous types of satellites that provide useful benefits for society, including satellites that carry phone, radio, or television signals for communication and entertainment purposes. Other satellites are used to monitor Earth's weather conditions, providing information that can tell us whether we should take an umbrella on our way out the door or even whether to take precautions to protect ourselves, our families and our property from severe weather or natural disasters. Space telescopes and research satellites allow us to explore what lies beyond our planet, while others let us see our planet in ways not possible from the ground - for example, without satellites, there would be no Google Earth!
Does space need a maid?
Each of us is familiar with the parental order to clean up the mess in our room. Why are we responsible for cleaning up the mess? Because we made it and it's our room.
Human actions can similarly "mess up" our planet; for example, the burning of fossil fuels is receiving a lot of attention these days because of its contribution to global warming. Just as we're responsible for cleaning the messes we make in our rooms, we are responsible for cleaning up the environmental damage that human actions cause on Earth - or face consequences that are direr than being grounded!
Well, just as human actions impact our environment here on Earth, space debris alters the extra-terrestrial environment, which begs the question: Do we have a similar obligation to keep space clean?
In addition to the potential harms that could result from space debris falling to Earth, there is the potential for space debris to crash into satellites or manned space ships and cause minor to potentially catastrophic damage. The potential for space debris to cause damage to other objects in space, thereby creating more space debris and increasing the odds for additional collisions, was theorized by scientist D.J. Kessler in 1991 and is known as the Kessler Syndrome. The implication from the Kessler Syndrome is that space exploration or satellite use could become seriously compromised due to the threat of space debris impact; so much so that, in time, it would no longer be practical to pursue it.
But is the potential for damage to man-made crafts and equipment the only reason not to "litter" in space? If we are obliged to keep space clean, does this obligation stem from the possibility that space debris can cause harm or because space is something that should be valued and protected outside of how it can affect humans? These are important questions that require societal discussion and debate. And as we've learned from recent revelations about climate change, it would be preferable to start having these discussions now, before we are faced with problems from which we may not be able to recover!
-- Sally Bean, JD, MA
About the Author
Sally Bean is currently a Senior Fellow in Clinical and Organizational Ethics at the University of Toronto Joint Centre for Bioethics and Trillium Health Centre. Her research interests include health law, healthcare organizational ethics, welfare economics, neuro-ethics, alternative dispute resolution, and public health ethics.
Want to read and learn more?
To read a press release from the US Space Command Fact Sheet on re-entry assessment, click here:
http://www.spaceref.com/news/viewpr.html?pid=4008
To read about the Kessler Syndrome (a theory that the volume of space debris is so high that objects orbiting Earth are struck by debris), click here:
http://en.wikipedia.org/wiki/Kessler_Syndrome
Access the original article by Dr. Kessler via this citation: D.J. Kessler (1991). "Collisional Cascading: The Limits of Population Growth in Low Earth Orbit". Advances in Space Research 11: 63.
