Spacex Rockets: Polluters Or Eco-Friendly?

With the increasing accessibility of space travel, concerns have been raised about the environmental impact of rocket launches. SpaceX rockets, for example, use kerosene and liquid oxygen, which create a significant amount of carbon dioxide emissions, as well as soot and other pollutants. While rocket launches are relatively infrequent compared to aviation, the pollution they emit reaches the upper layers of the atmosphere, which can have a disproportionate impact on the environment. Additionally, space debris and space junk are becoming significant issues, with over 150 million objects in orbit that need to be tracked to prevent collisions. However, some argue that the amount of carbon emitted by SpaceX rockets is insignificant compared to global industrial emissions, and SpaceX is exploring ways to make their rockets more environmentally friendly, such as by reusing rockets and capturing CO2 emissions to turn them back into rocket fuel.

SpaceX rockets emit carbon dioxide, carbon monoxide, and nitrogen oxides

Additionally, kerosene-fuelled rockets transport large amounts of black carbon, also known as soot, into the upper layers of the atmosphere. There, it remains for a long time, creating an umbrella that may contribute to global warming. The fuel is widely used because it is easier to handle than other fuels such as hydrogen. SpaceX's Falcon Heavy rocket emits more carbon dioxide in a few minutes than an average car would in over two centuries.

However, it is important to note that rocket launches are relatively infrequent, and their overall impact on the climate is smaller than that of aviation. The pollution caused by a year's worth of rocket launches is insignificant compared to even a day's worth of airline travel, cruise ships, or an hour's worth of cargo ships. SpaceX is also exploring ways to mitigate the environmental impact of its launches. For example, they plan to use renewable energy to capture CO2 from the air and turn it back into rocket fuel, which could be a cost-effective way to fuel their Starships and a vital process for potential missions to Mars.

Furthermore, the use of reusable rockets by SpaceX helps to reduce the resources required for the metal body of the rocket. While rocket pollution is a concern, it is not the only environmental impact of space exploration. Space debris and "space junk" from disused satellites and other objects accumulating in Earth's orbit are also significant issues that need to be addressed.

SpaceX rockets use kerosene, hydrogen, and methane as fuel

SpaceX rockets use kerosene (RP-1), hydrogen, and methane as fuel. Kerosene is a refined form of rocket fuel that produces carbon dioxide and water vapour when burnt. It also produces soot because some of the fuel doesn't burn completely. SpaceX's Falcon 9 and Falcon Heavy rockets use kerosene as fuel. The amount of carbon produced by three Falcon 9 rockets is approximately 4,000 tonnes per year, which is a relatively small amount compared to global industrial emissions. However, if SpaceX's plan for a rocket launch every two weeks comes to fruition, this amount of carbon will become a more significant problem.

Hydrogen has been used in various rockets, but SpaceX chose methane for its Raptor engine. Hydrogen has several drawbacks, including the need for extreme temperature control, leakage, low density, and high cost compared to methane. Additionally, hydrogen can cause hydrogen embrittlement, where hydrogen atoms alloy themselves into metal containers, weakening their structure.

Methane (CH4) is a naturally occurring gas found in abundance within soil and rock sediments below the Earth's surface. It is the simplest type of hydrocarbon, consisting of one carbon and four hydrogen molecules. SpaceX's Starship rocket is one of the first orbital rockets to use liquid methane exclusively as its fuel. Methane has several advantages over kerosene, including higher specific impulse, lighter weight, and reduced carbon production when burnt.

While SpaceX's rockets use kerosene, hydrogen, and methane as fuel, the environmental impact of their launches extends beyond fuel consumption. Space debris, for example, is becoming one of the biggest problems, with over 150 million objects needing to be tracked to prevent collisions with working spacecraft. Additionally, the location of exhaust deposition is a factor in pollution, as rockets pollute the upper layers of the atmosphere disproportionately, magnifying their damage.

SpaceX rockets create space debris, which can cause pollution on other planets

SpaceX rockets, such as the Starship, have been known to explode and rain debris from the sky. This debris can cause pollution on Earth, as well as in space. While SpaceX has stated that the debris from these explosions is non-toxic and does not contain any hazardous materials, the fallout from these incidents has still caused property damage and disrupted air travel.

SpaceX's rockets use RP-1 (a refined kerosene) and liquid oxygen as fuel, which creates a significant amount of carbon dioxide when burnt. While the amount of carbon emitted by a single rocket launch is relatively small compared to global industrial emissions, the company's plans for more frequent launches could lead to a larger carbon footprint in the future.

Additionally, space debris is becoming an increasingly significant issue, with over 150 million objects requiring tracking to prevent collisions with functioning spacecraft. The debris from SpaceX's rocket explosions contributes to this problem and could potentially cause further issues for future satellite launches and space missions.

The pollution caused by SpaceX rockets is not limited to Earth's atmosphere. The fallout from rocket explosions can reach other planets, such as Mars, and create debris and pollution there. This could have unforeseen consequences for the environment and any potential life on these planets.

While SpaceX's reusable rocket technology may help reduce the resources required for each launch, the company must also consider the environmental impact of its frequent launches and take steps to mitigate any negative effects, both on Earth and in space.

SpaceX rockets emit less pollution than aviation, but more frequent launches could change this

SpaceX rockets emit less pollution than aviation, but as the company plans to increase the frequency of its launches, this could change. The current fuel for Falcon Heavy is RP-1 (a refined kerosene) and liquid oxygen, which creates a lot of carbon dioxide when burnt. Kerosene-fuelled rockets also transport large amounts of black carbon, or soot, into the upper layers of the atmosphere, which can contribute to global warming. SpaceX's Falcon Heavy rocket emits more carbon dioxide in a few minutes than an average car would in two centuries.

However, the overall impact of rocket launches on the climate remains much smaller than aviation's due to their relative infrequency. Additionally, rockets like the Delta IV produce zero CO2, emitting over 600 tonnes of water vapour instead. SpaceX is also exploring ways to reduce the environmental impact of its rockets, such as by using a Sabatier process to extract CO2 from the air and turn it into rocket fuel, potentially powered by renewable energy.

The location where exhaust is deposited is also a factor in pollution. While rocket exhaust in the upper atmosphere can cause disproportionate damage, the lack of human activity around launch sites can sometimes benefit the surrounding habitats and local fauna.

SpaceX's planned launch of 12,000 satellites in the next seven years for its Starlink internet constellation will likely increase the strain on the environment, contributing to the growing problem of 'space junk'. The potential advantages of large-scale rockets are incredible, but private space firms like SpaceX must be aware of the potential negative impacts, both in space and on Earth.

SpaceX is developing processes to recycle carbon dioxide emissions and create fuel

SpaceX's rockets have been criticised for their environmental impact, with the Falcon Heavy rocket in particular being branded as "one of the dirtiest". The current fuel for Falcon Heavy is RP-1 (a refined) kerosene and liquid oxygen, which creates a lot of carbon dioxide when burnt. The amount of carbon emitted by three Falcon 9 rockets is approximately 4,000 tonnes per year, which is a relatively small amount compared to global industrial emissions. However, if SpaceX continues with its plan for a rocket launch every two weeks, this amount of carbon will rapidly become a more significant problem.

SpaceX's Starship rocket has also faced scrutiny for its environmental footprint, with concerns about frequent launches. The rocket uses methane, which, when burned, converts into carbon dioxide and water vapour. Methane is a greenhouse gas up to 90 times more potent in trapping heat in the atmosphere than carbon dioxide. However, methane combustion produces lower overall greenhouse gas emissions than burning oil or coal.

SpaceX does not publish its emissions, but the company is developing processes to reduce its environmental impact. For example, the Raptor engine has been designed to use liquid methane as fuel, which has a higher performance than other fuels, allowing the rocket to be smaller and produce less soot when launched. Additionally, several rocket start-ups are experimenting with sustainable alternatives to RP-1 made from waste plastic or biomass.

SpaceX is also addressing the issue of space debris, which is becoming one of the biggest problems in space exploration. The company is working to minimise the impact of any collisions or degradation of its vehicles, as the resulting debris can pollute other planets and pose safety hazards for future missions.

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