Pollution From Rocket Engines Spreads High Into the Earth’s Atmosphere

Researchers investigated the heat and mass transport and quick mixing of combustion byproducts to determine the possible impact of a rocket launch on air pollution.

The scientists simulated the exhaust gases and growing plumes at various heights along a typical modern-day rocket course.

They conducted this as an illustration of a two-stage rocket carrying passengers and commodities into Earth's orbit and beyond, and discovered that the influence on the atmosphere locally and briefly in the mesosphere can be considerable.

Rocket engine exhaust pollution

(Photo : Red Huber/Getty Images)

Reusable rocket technology has resulted in an increase in low-cost space travel, as demonstrated by commercial space missions by businesses such as SpaceX and Virgin Galactic.

What is unknown is how rocket propulsion system emissions cause substantial warming and chemical alterations in the atmosphere.

Researchers from the University of Nicosia in Cyprus analyzed the possible impact of a rocket launch on atmospheric pollution in the Physics of Fluids by researching heat and mass transport and the quick mixing of burning byproducts at elevations up to 67 kilometers into the atmosphere.

According to co-author Dimitris Drikakis, a better understanding of rocket emissions needs modeling and analysis of the hydrodynamics of rocket exhaust gases entering the atmosphere.

The scientists simulated the exhaust gases and growing plume at various heights along a typical modern-day rocket trajectory.

They did this to demonstrate a two-stage rocket capable of transporting people and payloads into Earth's orbit and beyond.

According to co-author Ioannis Kokkinakis, "we show that rocket pollution should not be underestimated since frequent future rocket launches might have a major cumulative influence on the Earth's climate," as per ScienceDaily.

The researchers discovered that the generation of thermal nitrogen oxides (NOx), which are components of combustion exhaust, may stay high up to altitudes with ambient air pressures that are higher than or slightly lower than the nozzles' exit pressure.

Simultaneously, the mass of carbon dioxide emitted by the rocket as it ascends 1 kilometer in the mesosphere is similar to that contained in 26 cubic kilometers of atmospheric air at the same height.

They discovered that the influence on the atmosphere may be considered both locally and briefly in the mesosphere.

While air currents will progressively move and mix the exhaust CO2 throughout the atmosphere, eventually reducing the CO2 to naturally occurring levels, the time scale over which this occurs is unknown. 

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Are space launches environmentally harmful?

Due to the use of solid rocket fuels, space launches can have a significant carbon impact.

Many rockets, on the other hand, are driven by liquid hydrogen fuel, which emits "clean" water vapor exhaust, despite the fact that the creation of hydrogen itself can create large carbon emissions.

Rocket engines emit trace gases and soot particles into the upper atmosphere, which contribute to ozone depletion.

Despite this, rocket launches are rather few, which means that their total influence on our environment remains considerably lower than that of aircraft.

But it's not only our immediate surroundings: space trash is becoming a rising worry as old satellites and other items pile up in our planet's orbit.

In July, Eloise Marais, an associate professor of landscape ecology at University College London, told The Guardian that she had spent a decade simulating the impacts of rocket launches.

She discovered that a single rocket launch may emit between 200 and 300 tons of CO2.

This roughly conforms to the estimates of Everyday Astronaut. The United Launch Alliance's Delta IV Heavy, which only burns hydrogen, wins with almost minimal carbon.

Both the SpaceX Falcon 9 and the NASA Space Shuttle emit around 400 tons of CO2 every launch.

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