The recent space launch of a Tesla roadster aboard a SpaceX Falcon Heavy rocket (video below) has once again raised the conversation level surrounding the issue of orbital debris. Orbital debris is “any human-made object in orbit about the Earth that no longer serves any useful purpose.” In December of 2017, J. –C. Lious, PhD, Chief Scientist for Orbital Debris, gave a presentation about the current state of orbital debris and its policies. In the 1990s, NASA was the first organization in the world to create a space debris policy with specific guidelines. Entitled the NASA Procedural Requirements for Limiting Orbital Debris, the organization spearheaded an effort to expand this policy throughout the entire United States Government. The United States is not the only country that is worried about space debris.
The Inter-Agency Space Debris Coordination Committee (IADC) is a collection of a spacefaring countries that has developed a set of international space debris guidelines. Space Debris has also been on the agenda at the United Nations since 1994. Since there are so many space debris committees there must be a lot of disagreement, right? Correct! The international community created at least four separate standards that all contain different guidelines and criteria governing space debris in Low Earth Orbit (anything below 2000 km). Many of these policies are not quantitative and contain phrases such as “minimize the probability of occurrence.” Of these organizations, NASA has been the global pioneer on orbital debris. They were the first to acknowledge the problem, and the first to set up measurable guidelines to manage it.
Even with all of these regulations, launches still occurred from January 2008 to September 2017 that did not comply with the guidelines set forth by NASA. These guidelines consist of three simple rules; the post mission orbital lifetime must be less than 25 years, the threat of orbital debris from a mission explosion must be less than 0.001 and finally, the reentry human casualty risk must be less than 1 in 10000. Examples of missions that did not follow these rules are NOAA-19, with an orbital lifetime of 500 years, and MMS Atlas 5, with a human casualty risk of 1 in 600. NASA is trying to create better compliance for the future projects by working on a set of new standards that include reducing orbital debris during normal operations, minimizing the amount of debris created by accidental explosions, and by launching missions with disposable space structures.
OPINION: The Falcon Heavy launch was definitely a site to see, but the Tesla that is in space now is unnecessary. Yes, I think it’s comical, and I understand the promotional value that Elon Musk received for shooting a Tesla into space. But at what cost? Currently, we don’t know where it is going. All we know is that it is going to pass Mars orbit in about 6 months and eventually make it back to somewhere around Earth. Most orbital debris serves a useful purpose at some point during its mission but Musk’s Tesla was nothing more than a rocket payload. Sustainability is on everyone’s minds right now, but what about space sustainability? How long will it be until we need to start worrying about not being able to see the sky because of orbital trash?
Link: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20170011662.pdf
Liou, J.-C. 2017. Orbital Debris Briefing. NASA Technical Reports Sever: JSC-E-DAA-TN50234.