Technology

Space Tourism and Its Environmental Cost

space travel

On June 7, 2019, NASA announced that starting in 2020, the organization aims to start allowing private astronauts to go on the International Space Station, with the use of Space X’s Dragon2 module and Boeing’s Starliner module for public astronauts, which is planned to be priced at $35,000 per day for one astronaut.

This news has received myriads of reactions; some are excited about this possibility, while others are concerned regarding the long-term cost of this adventure.

Space tourism refers to space travel for recreational purposes. There are several different types of space tourism, including orbital, suborbital and lunar space tourism.

Today we’ll discuss the environmental cost and effects of space tourism on the earth’s atmosphere.

The effects of rocket launches on the environment haven’t been researched to the fullest, but we do know enough to be concerned about their impact. It’s not just about carbon: An uptick in launches can also cause long-term damage to the ozone layer. The chemicals burned by rockets work together in the upper atmosphere, and experts say they could eventually deplete up to 1% of the ozone keeping us safe from the sun’s radiation.

Though rockets today are increasingly fuel-efficient, it still takes tremendous energy to shoot them into space. A SpaceX Falcon 9 rocket, for example, largely consists of a tank to hold the 147 metric tons of refined kerosene used to reach orbit.  Each Falcon 9 launch produces approximately 150 metric tons of carbon, which would add up to a total of around 4,000 metric tons per year if SpaceX achieves its goal of a launch every two weeks.

The bigger problem with rocket launches is damage done to the atmosphere itself. As a rocket moves through the upper atmosphere, burning kerosene-based fuel as it goes, it deposits chemicals including chlorine into the air around it. Chlorine destroys the ozone molecules that shield the planet from the sun’s rays, contributing to global warming.

Chlorine isn’t the only thing damaging the ozone layer. Burning rocket fuel also creates black carbon, or soot, and aluminum oxide. The soot particles form a “black umbrella,” which absorbs sunlight and heats up the air around it, and the aluminum oxide particles reflect heat away like aluminum foil. Together, these two effects make the surface of the planet cooler.  And as it cools the surface of Earth at the expense of heating the upper atmosphere. A warmer upper atmosphere means the chemical reactions which deplete the ozone layer happen even faster.

Basically, as the upper atmosphere gets warmer, the ozone protecting our planet is destroyed faster.

Because of this lack of research, we don’t know exactly how fast rocket launches will deplete the ozone layer – but it’s unlikely to be good news. Current estimates show that rocket launches cause up to 0.1% in ozone loss, If launches go up by a factor of 10 in the next few decades as governments and companies launch more satellites and tourists head up into the cosmos, we could wipe out 1% of the ozone layer. When you consider the 3% loss of ozone that caused us to ban CFCs under the Montreal Protocol in 1989, the effect of rocket launches doesn’t seem so minuscule any more.

The elite privilege of space tourism would end up harming the earth’s atmosphere thereby ultimately impacting that vulnerable section of the society, who are worst prepared for what is coming.

-Aditya Patil

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