Friday, July 2, 2021

The Men, Their Rockets, and Their Atmospheric Responsibilities

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We definitely live in a time when there is tremendous innovation around space travel. Three billionaires are advancing it in ways unimaginable a few years ago to most of us except for science fiction writers. However, it is important to note that the emissions from space travel are entirely unregulated. Now that rocket ships are becoming more common, it is worth accounting for their atmospheric impacts.

It is important to highlight that three billionaires are behind this space boom:  Elon Musk, Jeff Bezos, and Richard Branson. Each is taking a different approach to space exploration and I want to review their atmospheric impacts. Before I do so, however, I do want to point out that each individual represents what I call a metamodern approach to sustainability (you can read my take on metamodernism  and sustainability here at this link). Each individual is a strong proponent of sustainability initiatives. However, space travel is demonstrably a very bad thing for the environment. The idea of the two (environmentally damaging space travel/space travel brought about by proponents of sustainability) existing at the same time is what makes these initiatives distinctly metamodern. 

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It is also important to point out that there have also been many critiques of space travel from an equity lens. It is very expensive and bad for the environment and very few people get to experience its benefits. Thus, very few get the experience and many more will have negative consequences (deterioration and pollution of the atmosphere). Certainly there are intangibles that we may all benefit from at some point. For example, satellite technology has certainly improved our lives in measurable ways. However, for many, the overall costs outweigh the benefits.

Let me now review the three distinctly different approaches to space travel. Before I start, I want to stress that I am mainly reviewing the fuel sources. There are certainly other environmental impacts one could review with space travel, such as rocket components. However, burning fuel has the greatest atmospheric impact to space travel and it is important to understand what happens to the fuel as it burns. After reviewing the approaches, I'll highlight the atmospheric impacts of the fuels.

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Elon Musk SpaceX approach. SpaceX is perhaps the most advanced space exploration group of the three. Instead of focusing on space tourism, SpaceX has largely replaced NASA's regular space shuttle flights. There are a range of rocket types that are in use. The Falcon rockets, which have garnered attention for their spectacular reentry and reusability, use mainly fueled by kerosene and oxygen. However, SpaceX developed methane based engines that will be used for longer missions. In addition, SpaceX uses hypergolic fuels consisting of nitrogen oxides and hydrazines in some engines.

Jeff Bezos and Blue Origin approach. Bezos's company, Blue Origin, is famous for auctioning off a seat on a space tourism trip for an 11 minute ride into space for 28 million dollars which will take place July 20 of this year. Blue Origin rockets use methane fuels.

Richard Branson and Virgin Galactic approach. Unlike the previous two individuals, Branson is not as interested in getting into the big satellite and exploration game. Instead, his focus is clearly on space tourism. He has a launch scheduled for July 11th of this year. The Virgin Gallactic rockets use hydroxyl-terminated polybutadiene (HTPB) and nitrous oxide as a fuel.

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There have been many studies on the atmospheric impacts of all of these fuels and a quick Google Scholar search will reveal them. However, the problems fall within three broad categories.

First rocket fuels release tons of black soot into the atmosphere every year. This soot can absorb heat to increase atmospheric temperatures. Second, burning of rocket fuels release greenhouse gases which are also responsible for increasing atmospheric temperatures. And third, some of the rocket fuels release dangerous compounds (particularly perchlorate) which can have health impacts. Some of these compounds do damage to the ozonosphere.

As I noted, the atmospheric releases are largely unregulated and many have called for greater regulation of the industry. It is important to highlight that each of the companies have stated that they are working on green approaches to space travel. For example, Elon Musk hopes to extract carbon from the atmosphere to use as fuel. However, for now, we live in the very metamodern world where space exploration companies are heavy polluters while their brands go green.

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