Floating into space and other ways of getting there (2/2)
How to get into near-space, orbit, or outer space without burning up or polluting the atmosphere during the climate emergency on Earth? Written by scientists, engineers, artists, curators and cultural specialists in space exploration, the book “Space Without Rockets” (UV Editions – 2022) adresses the ways in which we could steer out our spaceship Earth and travel away to the Moon, the planets, the stars and beyond, sustainably. Makery publishes three of the full texts from this essential reading. First text (part two) by Rob La Frenais.
Rockoons and other stratospheric options
Rockoon (rocket plus balloon) technology has a relatively long history in the chronology of spaceflight, the first being fired from the Aerobee firing cruise of the U.S.S. Norton Sound in March 1949. “The basic idea was to lift a small sounding rocket high above the dense atmosphere with a large balloon in the Skyhook class. Once enough altitude is attained, the rocket is fired by radio signal straight up through the balloon.” Then in the ‘50s James Van Allen discovered radiation in what was to become the Van Allen Belt, using a rockoon. “James A. Van Allen first put rockoons to practical use when he and his group from the University of Iowa fired several from the Coast Guard Cutter East Wind during its cruise off Greenland in August and September 1952. 41 Van Allen was looking for high-altitude radiation near the magnetic poles and needed a vehicle that could reach well over 80 km (50 mi) with an 11-kg (25-lb) payload and yet still be launched easily from a small ship. The rockoon was the answer. With his rockoons, Van Allen detected considerable soft radiation at high altitudes – much more than scientists expected. This was one of the first hints that radiation might be trapped by the Earth’s magnetic field. One drawback to the rockoon was that it had to be fired before high-altitude winds carried it out of radio range.” (‘NASA Sounding Rockets 1958-68, A Historical Summary’, William R. Corliss.)
The rockoon has undergone a small renaissance in recent years and the European Space agency has funded and encourage several small scale enterprises using stratospheric launches and rockoons. One is a company based in Wales, B2Space who have already done a test flight in 2020, on the facilities of the new Spaceport Snowdonia, in North Wales, achieving altitudes above 30km high and temperatures below the -50 degrees Celsius. The flight carried the necessary payload for a rockoon launch, but have not yet got into orbit.
I asked B2Space co-founder Valentin Canales how far they are to launching their first rockoon. “We have tested (ground and strato- spheric flight) all elements of the rockoon technology so far including the Large Zero Pressure Balloon and all associated navigation and safety systems, the remote rocket arm and ignition system, rocket launcher pointing, positioning and stabilisation platform A final demonstration of all elements will be performed late September or early October 2022”. I asked him how much more sustainable are rockoons in terms of propellant use for low earth orbit launches? “By skipping the highest density part of the atmosphere, B2Space reduces Delta V losses up to 2km/s, which is translated into more than 70% propellant saved for an equivalent launcher. That, linked to the fact that B2Space is working on its proprietary bio-propellant, will make B2Space one of the most environmentally friendly launch companies in the world . Another, Zero2 Infinity, based in Spain, boldly goes with the following confident publicity: “From the public to the gurus of aerospace, most people think that space will remain within the realm of a few super- powers, large defence contractors and the odd billionaire…but we won’t settle for that. At Zero2 Infinity we choose to carry the burden of proof that there is indeed a better way one that allows you to realise your dreams in space.” Mainly promising high flying stratospheric launches for testing low earth orbit satellites, they also intend “to fly an efficient rockoon as a reusable sounding rocket for microgravity, science, component certification, etc”. Interestingly they aim to use sea launches as well as land launches saying “sea launches decrease administrative restrictions and the areas to avoid: highways, populated areas, or military terrain” and that “sensitive or confidential payloads are better protected at sea than on land”. In researching these balloon technologies the cold hand of the military or border forces is never far away. This company also has a sideline in space tourism, offering 30 km flights “over 99% of the atmosphere.”
Another company, SpaceRyde in Canada, literally a garage start-up by Iranian husband and wife team Saharnaz Safari and Sohrab Haghighat, backed by the Canadian Space Agency, say they want to be the ‘Uber of Space’ . They aim to launch what they call a ‘smart rocket from a balloon 30 km up at a pricetag of $250,000 per 150 kilograms, envisioning a ‘rocket network, delivering small satellites into orbit. They plan their first launch next year. How did the progress of rival Rockoon companies like these compare to B2Space? Valentin Canales: “Regarding other competitors (Zero to Infinity or Space Ryde), B2Space is much more advanced in terms of stratospheric flight capabilities, having conducted dozens of flights. This places us in an ideal place to start the scale up of our launch vehicle and start servicing our customers from 2024”.
Another company specialising in stratospheric balloon flights, based not far away from where I am writing this is Zephalto, founded by test pilot Vincent Farret d’Astiès which offers “Travel towards the stars without polluting, in harmony with nature.” Unusually, using solar energy like artist Tomas Saraceno’s Aerocene, they have entered a partnership with CNES in France. “Since 2016, in the heart of Hérault, in Occitanie, Zephalto has been developing a unique and highly technological know-how with the CNES: Céleste, a balloon capable of tak- ing voyagers into the stratosphere for an unlimited flight time and an unforgettable experience in unprecedented conditions of comfort and safety. This know-how is based on two major technological innova- tions in the world of balloons: the altitude regulator and the reusable envelope. Thanks to these technological advances, Céleste is com- pletely ecological, runs on solar energy, and can be reused indefinitely… Solar energy also allows for take-offs and landings without the need for lots of infrastructure and offers a great freedom of movement by following the wind.” However there are no plans for hybrid launches into orbit as far as I can see.
Safe space tourism by balloon, to be able to see the edge of of the blackness of space and the curvature of the earth without burning up pro- pellants is by no means guaranteed. In 2017 a test hydrogen-filled balloon at the Tucson headquarters of a US company called World View exploded, causing them to go over to helium (which is in short supply on Earth). A new US company, Space Perspective, is continuing with hydrogen, insisting that with modern engineering and construction method it is safe, and that helium is needed in hospitals and sat- ellite technologies. Another Spanish start-up EOX-Space is also offering space tourism at 40 km, but is also using rare helium.
It’s fine to lower the costs of space tourism this way and while high altitude stratospheric balloon flights can reduce the demand for waste- ful, polluting and expensive flight tickets with Virgin, Spacex and Blue Origin – as far as I can see – unless JP Aerospace can develop its orbital ascender, or rockoons can reduce the amount of propellant used, none of these companies are getting us closer to sustainable travel to space.
Space Elevators and towers: are they really coming?
What is a space elevator, actually? A space elevator is an electric vehicle called a “climber” that drives up and down one thin tether between the ground and a satellite in stationary orbit, using another outside tether for balancing with centrifugal force. The total length of the tether would have to extend to 100,000 kilometres. This would be a permanent portal into space, but the tether is the main problem to construct. Although in another article in this handbook, space elev- ators have been ruled out as being at all feasible in the near future, some companies have been putting some serious money into research and development. One is Liftport, founded in 2003, in Washington DC, who have been researching an Earth Elevator, but have found that to build the tether to lift ‘climbers’ into space “is the part of the Elevator that is preventing us from building one here on Earth today. The combined forces of gravity and centripetal acceleration on any known material in the shape we need would snap it. As such we need a material with extremely high tensile strength that is also very light. Technically, we could build an Earth Elevator today with existing materials, but it would need to be so large to withstand the forces acting upon it that it would be completely impractical to build”. So they have put that on hold for what they see as a more feasible project, a Lunar Elevator “to create a permanent system on the Moon that is reusable, replaceable and expandable, to open up the resources present on the Moon, expand our presence in space, and improve life here on Earth.” The idea is to build a ‘spaceline’ from the moon to near the Earth, devel- oped by astrophysicists Zephyr Penoryre and Emily Sandford, which would orbit Earth once a month. But then you’ve got to get all the com- ponents to the Moon and that means more rockets.
Thoth Technology in Canada have patented an Earth Space Elevator concept invented by founder Brendan Quine, starting with pneumatic towers. However this would technically only be an elevator tower only going as high as 15km, as far as I can see, providing a platform to launch spaceplanes closer to near earth orbit. Thoth CEO Caroline Roberts describes the benefits of the new technology here: “Access to near space is set to revolutionise the way we do business on Earth. The advantages for energy generation, communications and space tourism are immense. Thoth plans to construct pneumatic ThothX towers to access first 1.5 km and then 15 km above Earth within a decade.” So this is actually closer to Konstantin Tsiolkovsky’s Space Tower.
In Japan, the Obayashi Corporation, which is a massive construction company building bridges and highways among other things, have announced their intention to complete a working space elevator by 2050. They say that a computer simulation shows they have the ability to construct the ribbon or cable, using carbon nanotubes and starting in around 2031.They would use the climbers to actually construct the cable, slowly over 20 years. “The construction process consists of deploying the cable and constructing the facilities. It is necessary to analyse the cable dynamics in order to estimate the characteristics of the cable, counter-weight, facilities and climbers, and in order to deter- mine the construction procedures. Parameters for the cable dynamics include tension, displacement and elongation of the cable due to ascending climbers, masses of counter-weight and cable, wind, and fixed loads of facilities. With the help of a computer simulation of the equations of motion, we designed the system and determined the con- struction process…”
It will take roughly 20 years to construct the cable, the impacts of wind or Coriolis force on cable displacement are small, and it is essential to fix one end of the cable to the earth’s surface, always applying pre-tension at the ground end. According to the plan, a 20-ton cable is deployed initially, and is reinforced 510 times by climbers up to 7,000 tons, ascending in succession over roughly 18 years. The facilities are then transported and constructed within one year.” (‘The Space Elevator Construction Concept’, November 4 2014)
However, they too say “The current technology levels are not yet suf- ficient to realise the concept, but our plan is realistic, and is a stepping stone toward the construction of the space elevator.” The simulation was worked out by engineers who built the worlds highest free-standing tower, the Tokyo Skytree, in 2012. Speaking in a recent article in Redshift/Autodesk on the Obayashi Corporation’s space elevator, Professor Yoshio Aoki of the Department of Precision Machinery Engineering at Nihon University introduces another aspect but takes a more upbeat note: “We still don’t have any measures to sufficiently address legal and safety issues of how we should deal with threats such as terrorism. Dealing with such difficult aspects will be required mov- ing forward. But if we are able to get past such issues, and if more cor- porations support us, I believe that an operating cargo transport space elevator is entirely possible in the 2030s.” More of a think-tank, but also coming up with real proposals, is the International Space Elevator Consortium, advised by artist Arthur Woods and David Raitt, formerly of ESA and others. They announce on their website. “The Modern Day Space Elevator is Closer than You Think!”
It’s good to hear such optimism in an industry that is so wedded to short-term solutions. The title of this handbook ‘Space Without Rockets’ points to a dream that is still far from realisable but nonethe- less is an urgent wake-up call to the space industry to start putting some serious money and research into sustainable alternatives to getting into orbit.
Note: Just as I was completing this survey I was told about a new technology that is being developed at SpacePort America, SpinLaunch, as mentioned by Ewen Chardronnet in his introduction. It’s raised 110 million dollars funding and is an orbital accelerator, literally shooting vehicles into space. From their website: “SpinLaunch is an innovative new space technology company that has created an alternative method for putting 200 kilogram class satellites into low earth orbit. Unlike traditional fuel-based rockets, SpinLaunch uses a ground-based, elec- tric powered kinetic launch system that delivers a substantially less expensive and environmentally sustainable approach to space access”. It’s initial 33 metre test launcher launched 4 carbon-fibre aeroshells flown at supersonic speeds in late 2021 at a cost of 7 million dollars. It is proposing to build a 100 metre launcher capable of reaching orbit by 2025. Although SpinLaunch will get the aeroshells out of the atmos- phere into suborbital space it will still need a small rocket to reach the 28,000km/h velocity needed to enter orbit. So not quite space without rockets yet.
