By Tom Batchelor,
Published by The Independent, 22 July 2021
Calculating effect of each rocket launch on earth’s atmosphere will require detailed modelling
Amazon founder Jeff Bezos became the second billionaire in a little over a week to ride in his own rocket into space when New Shepard blasted off on Tuesday.
The businessman was accompanied by his brother, an 18-year-old from the Netherlands and an 82-year-old aviation pioneer from Texas for a 10-minute flight on his company Blue Origin‘s spacecraft.
During the flight, the capsule reached an altitude of about 106 kilometres after the booster accelerated to three times the speed of sound (Mach 3).
Unlike Richard Branson’s piloted Virgin Galactic rocket plane, which was successfully launched on 11 July, Mr Bezos’ capsule was completely automated and required no official staff on board for the flight.
Scientists say that emissions from rocket engines have historically been seen as small but as the frequency of launches increases and larger rockets are used, the impact is likely to grow.
- Can we really move heavy industry to space to solve the climate crisis, as Jeff Bezos has suggested?
- Jeff Bezos calls for moving ‘all polluting industry into space’ after private rocket trip
- Billionaires racing to space can’t escape reality of the climate crisis
Traditional rocket emissions trigger chemical reactions which deplete the ozone layer, experts Martin Ross and James Vedda warned in a 2018 report on the subject.
Space launches also inject particles into the stratosphere which absorb and reflect solar energy, heating the stratosphere while cooling the surface. These thermal changes also lead to the depletion of the ozone layer, their paper said.
However Blue Origin’s rocket was powered by a mix of liquid hydrogen and liquid oxygen. The propellants are much cleaner than conventional rocket fuel.
Mr Branson’s VSS Unity rocket used a hybrid mix of solid and liquid propellants, while the Space X Falcon project relies on liquid oxygen and a rocket-grade kerosene called RP-1.
Darin Toohey, an atmospheric scientist at the University of Colorado, Boulder, told Live Science that the main emissions from New Shepard would be “water and some minor combustion products, and virtually no CO2.“
However in a 2019 paper co-authored by Mr Toohey and Mr Ross, the men warned that “water vapor emissions from individual launches can notably impact the mesosphere and ionosphere” – two much higher layers in the atmosphere.
“Although not presently a global concern, at some increased launch rate, upper atmosphere launch plumes will become ubiquitous and so affect global mesospheric and ionospheric processes and properties,” the scientists said.
The Blue Origin project is designed to use a reusable launch vehicle with landing gear that deploys for touchdown, eliminating the need to build new, resource-hungry rockets and capsules.
Much of the resulting carbon emissions from the space project are likely to result from research and development work, while a significant part of the environmental impact of the launch itself is expected to be from the flights taken by the crew in order to gather in Texas.
The carbon emissions from a one way flight in economy linking the Netherlands – where New Shepard’s 18-year-old passenger, Oliver Daemen, hails from – to Texas totals around 0.4 tonnes, for example.
Ultimately, calculating the overall effect of each of these rocket launches on the planet and its atmosphere will require further, detailed studies.
But Eloise Marais, an associate professor in physical geography at University College London said none of the rocket propellants were totally clean.
“Large quantities of water vapour are produced by burning the BE-3 propellant, while combustion of both the VSS Unity and Falcon fuels produces CO₂, soot and some water vapour,” she said in an article for The Conversation.
“The nitrogen-based oxidant used by VSS Unity also generates nitrogen oxides, compounds that contribute to air pollution closer to Earth.
“These gases and particles have many negative effects on the atmosphere. In the stratosphere, nitrogen oxides and chemicals formed from the breakdown of water vapour convert ozone into oxygen, depleting the ozone layer which guards life on Earth against harmful UV radiation.
“Water vapour also produces stratospheric clouds that provide a surface for this reaction to occur at a faster pace than it otherwise would.”
This week’s Blue Origin space trip is also attracting lawmakers’ attention, with a proposal to tax the trips just as conventional flights through the troposphere currently are.
On Tuesday, the same day that Mr Bezos blasted into space, Earl Blumenauer, who sits on the tax-writing Ways and Means Committee, proposed legislation that would tax space travel for non-scientific research purposes.
”Space exploration isn’t a tax-free holiday for the wealthy,“ the Democrat from Oregon said.
”Just as normal Americans pay taxes when they buy airline tickets, billionaires who fly into space to produce nothing of scientific value should do the same, and then some.“
See: Original Article