Jeff Bezos' joyride into space Tuesday morning has - like Richard Branson's VSS Unity launch- been hailed as some kind of major space achievement. It wasn't, and in the scheme of things not even as significant as Alan Shepard's suborbital 'Freedom 7' flight aboard a Redstone rocket 60 years ago. Nor is Bezos an "astronaut" like Shepard was. He was, for all intents and purposes, a passenger aboard an automated craft controlled from outside. An astronaut- by contrast- is a trained space vehicle occupant who on any given mission has one or more assigned operational roles. The only role Bezos and his crew of three had was to frolic in zero g at the apogee of their jaunt and gaze through the giant capsule windows at the Earth below. Merely getting to the Karman line or passing it does not make them "astronauts" but rather marginal space tourists.
Where Bezos does deserve credit is in the Blue Origin craft itself, which was a self- supported rocket delivering over 100,000 lbs. of thrust to take the crew in its capsule 62.4 miles up. There was no "mother ship" needed to carry the craft up to some designated pre-launch altitude like Branson's VSS Unity.
Bezos himself made a number of grand claims on the future of such commercial space travel - which we can take with the proverbial grain of salt- because for the next 50-100 years at least it will only be for the wealthiest humans. He also voiced the need for protection of Earth, our only viable home planet, including "moving all industrial activities into space". In his words in one of his interviews:
"When you get up into space and see the Earth's atmosphere, it's so thin and fragile looking so you do want to take care of this planet. This sounds fantastical but we can move all heavy industry and polluting industry off into space."
He estimates "many decades" - 50 to 100 years- to do that, but the rapidity of climate change will ensure Earth is toast before the first Earth-polluting space factory is operative. (See last link which follows this post) It was also disingenuous of Bezos to compare such a monstrous effort to the development of air travel "from Kitty Hawk to the 787s of today." Unappreciative of the fact it's whole twenty orders of magnitude difference between advancing air travel from known aeronautics and the physics of jet engines - to moving whole polluting factories into space and making them efficient and operational.
Bezos also proclaimed that the Blue Origin rocket engine generates power but with minimal environment impacts. Overall, we still know very little about the environmental impacts of space tourism, and we likely won't find out until launches occur with far greater frequency. A report published by The Aerospace Corporation provided the basis for Blue Origin's claim that its rockets have "minimal" ozone impact. But that doesn't mean no impact.
Bezos claimed in a post launch interview yesterday that his hydrogen rocket fuel is a "clean", environmentally friendly energy source. But is it? The Blue Origin rocket which Bezos and his crew rode yesterday actually combines liquid hydrogen and liquid oxygen in its engine to generate thrust, meaning "the main emissions will be water and some minor combustion products, and virtually no CO2." This according to Darin Toohey, an atmospheric scientist at the University of Colorado, Boulder.
Water in rocket exhaust can increase the number of clouds in the atmosphere, Toohey added, including the iridescent "mother-of-pearl" clouds often seen at sunset after a launch. These can impact the upper atmospheric layers known as the mesosphere and ionosphere, but because the number of rocket launches is so low at present, they are not much of a concern in climate modeling.
Carbon dioxide pollution from spaceflight is still fairly negligible, with rockets accounting for around 0.0000059% of all CO2 emissions in 2018, according to Everyday Astronaut. (By comparison the airline industry churned out around 2.4% of global CO2 emissions that same year). But while ice and clouds can reflect sunlight back into space and reduce global heat, water vapor is a more potent greenhouse gas than carbon dioxide, and the longer that vapor remains in the atmosphere, the greater it will heat our planet.
Large quantities of water vapor are produced by burning the BE-3 propellant, while combustion of both the VSS Unity and Elon Musk's Falcon fuels produces CO₂, soot and some water vapor. The nitrogen-based oxidant used by VSS Unity also generates nitrogen oxides, compounds that contribute to air pollution closer to Earth.
Which is good to know. At least Bezos "clean" rocket fuel brag therefore seems accurate. But what about his other claims yesterday about making the Earth more livable for its teeming billions, and doing something about climate change. I suspect we need to take this with another grain of salt especially when Bezos said in a 2018 interview published on Business Insider:
"The solar system can easily support a trillion humans. And if we had a trillion humans, we would have a thousand Einsteins and a thousand Mozarts and unlimited, for all practical purposes, resources and solar power unlimited for all practical purposes. That's the world that I want my great-grandchildren's great-grandchildren to live in."
Excerpt:
Once upon a time, long long ago, people with names like John Glenn, Alan Shepard, Buzz Aldrin, and Sally Ride blasted into space. None was selected on the basis of income or wealth, but on skill and rigorous training. Their heroism – and we regarded them as national heroes – symbolized America’s technological prowess and egalitarianism.
....Today’s space race could not be more different. Bezos, Branson, and Elon Musk, the third billionaire racing into space, aren’t “we.” There’s no common good in their achievement. They symbolize the extreme apex of wealth today, some of it gained by paying their workers rock-bottom wages and shutting out competitors. They’re closer to the robber barons of the first Gilded Age.
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