===== ASTRONAUTICAL EVOLUTION =====

Issue 30, 1 May 2008 -- 39th Apollo Anniversary Year

  1. BIS Symposium: "Next Steps for Space Infrastructure"
  2. Celebrating (?) the Tunguska asteroid strike 100 years ago
  3. "Europe should give up on sending men and women into space" -- Martin Rees

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(1) BIS Symposium: "Next Steps for Space Infrastructure"

by Stephen Ashworth

The British Interplanetary Society marked St George's Day with a one-day symposium to discuss the future direction for space infrastructure.

Richard Osborne (Airborne Engineering Ltd) described development of the Canary research rocket. This is a flying test-bed to support the Skylon/Sabre SSTO spaceplane programme by flying an innovative rocket nozzle called the E-D (expansion-deflection) nozzle. So far there have been a number of static tests at the Reaction Engines site: over 10 cold flow tests, 6 hot firings of a calibration engine and 4 hot firings using the nozzle itself.

Whereas a conventional rocket nozzle has optimum efficiency at only one atmospheric pressure, and hence only one altitude, an E-D nozzle adapts to different external pressures, and hence preserves optimum efficiency at all altitudes from sea level to space. If applied to Skylon, it should be capable of reducing the takeoff distance by 500 metres, and of adding half a tonne to the payload.

Flight tests are anticipated in the near future.

(Link to Airborne Engineering here, and click on Rocketry to see the UK's hilarious answer to the Space Shuttle.)

Richard Varvill (Technical Director, Reaction Engines Ltd) talked about the Skylon project itself. Work on this is proceeding at Culham in Oxfordshire, thanks to private investment. The British government has recently shown a much more friendly face to Skylon, but is still not supporting it in any financial sense. There are a number of areas of ongoing research, the most important of which concerns the innovative heat exchangers, which are essential to the Sabre engines in their airbreathing mode.

(Link to Reaction Engines here, with images of Skylon in orbit, and the Skylon-derived intercontinental transport Lapcat that was in the news recently.)

Alan Bond (Managing Director, Reaction Engines Ltd) talked about his vision of a flexible space infrastructure based around Skylon as the launch vehicle. The most important orbital element is a Base Station in a low Earth orbit inclined at 28.5 degrees to the equator. Due to orbital precession, this comes into the same alignment with a given terrestrial launch site once every three days, when it could be accessed by one Skylon, or even by several, launching in quick succession.

This setup could then be developed further with a small orbit insertion rocket stage, an orbital transfer vehicle operating out of the Base Station, and a large Mars transfer stage for the big lunar and interplanetary missions.

He emphasised that the most important advantage of a reusable launch vehicle is its improved reliability compared with throwaway rockets. Each Skylon is expected to be good for 200 round trips to orbit and back -- poor by aviation standards, but clearly a revolution by space standards (for comparison, the most frequently used Shuttle orbiter, Discovery, has made 34 flights spread out over 24 years -- its 35th flight is due later this month).

Simon Feast (Reaction Engines) described the Base Station in detail. It looks nothing like the ISS or any previous space station. It is basically a large, unpressurised, cylindrical box, big enough to contain an entire spacecraft for a Mars mission with 6 astronauts, and with propellant tanks, living quarters and solar panels attached around the outside. Its main purposes are to provide uniform interior lighting conditions for the assembly of vehicles for lunar and planetary flights, to provide anchor points and handling facilities for their component parts, and to prevent the assembly work from generating space junk -- aptly illustrated with an image of a space-suited astronaut chasing a runaway spanner.

Interestingly, this concept restores the original vision of early space thinkers -- Hermann Oberth, Guido von Pirquet, Willy Ley and Wernher von Braun -- that the space station should act as an assembly point and refuelling station for deep-space flights. Whether there is a market for it under present conditions is another question.

David Ashford (Managing Director, Bristol Spaceplanes Ltd) defined the beginning of the New Space Age as the time when the cost of access to orbit becomes similar to the cost of going to Antarctica. We could be there in 15 years time. He emphasised that the Bristol Spaceplanes team has an aircraft heritage: their design philosophy is to build an aircraft that happens to be able to reach Mach 25 (at which speed it is in orbit).

He presented a schematic graph showing numbers of flights per year against time: when balloons were the only method of achieving manned flight, the rise in numbers of flights was barely perceptible, but after the invention of the aeroplane, the graph shot upwards. Extrapolating into the near future of spaceflight, he saw, again, only a very slight rise in numbers of flights while ballistic missile technology was the only method of getting into orbit (the current situation), but again a spectacular rise in activity once spaceplanes were in service.

My own presentation took a broader view. The potential resources of space are vast, and this motivates an analogy between the 18th-century Industrial Revolution and a coming 21st-century Space Industrial Revolution. Then, the key strategic resources were coal and iron; in space, they can be expected to be near-Earth asteroidal water (in the trillions of tonnes) and solar power (in the trillions of terawatts). A roadmap to the new age of space development must therefore encompass these key strategic resources, plus a convincing demonstration of human life in space. It requires some activity which has the potential for exponential growth, and I discussed asteroidal water mining as an example of this.

I was the only speaker not affiliated to an astronautical company or university engineering department, though my day job in publishing at the Voltaire Foundation in Oxford has certainly helped guide my thoughts towards the parallels between the 18th century and today.

Mark Hempsell (Bristol University) gave a spirited defence of his controversial Habitation Extension Module (HEM) design study. His purpose had been to widen the debate about UK government participation in the ISS, to show what the UK could do and how it might benefit. He emphasised that there are areas of science such as pharmaceuticals and microbiology in which the UK has traditionally excelled, but which are now suffering as a result of the total exclusion of UK scientists from the ISS.

The 600 million pounds (over several years) which the programme would cost would have to be new funding, not taken from any other UK science budget. Yet it is such a modest amount that, even if the UK government did commit to finding this new money, it would still be able to preserve intact its status (its "badge of honour", Mark said, with heavy irony) as the European nation which spends least on space in proportion to its GDP. (Peak spending would be 170 million pounds in 2010 and 2011.)

Mark is of course very much associated with the Skylon programme, and he also emphasised that, if the HEM programme went ahead, it would not compete with Skylon for government funding, but on the contrary would even support it by providing an early flight test of the Skylon avionics.

Finally, John Gimson (AeroSekur Ltd) described his company's work in inflatable space structures. His company is making the airbags to cushion the descent of ESA's EuroMars probe (due for launch in December 2013). They have also ground-tested an inflatable heatshield, and developed a self-sealing technology to repair an inflatable after puncture by a micrometeoroid. He sees large potential for agriculture in space ("agrispace") to support off-planet human life.

In general conversation during the breaks in presentations, I noticed that one or two people were highly sceptical about NASA's Constellation programme now in preparation. The opinion was that the next US president would lack any commitment to the Moon/Mars plans, the Ares V would not be developed and the return to the Moon not happen.

This sobering possibility is a useful corrective to the enthusiasm being being generated at NASA and worldwide through the Global Exploration Strategy. Although the outcome of the Bush Vision for Space Exploration depends partly on unpredictable personalities and events, we can foresee at least one development that will put strong downward pressure on NASA's budget -- see "The Vision for Space Exploration and the retirement of the Baby Boomers (part 1)" (thanks for the reference, Jacqueline) (look out for part 2, which has not yet been published).

I can only reiterate my view that the market forces behind the existing global tourism and industrial energy industries are likely to prove more reliable and more sustainable drivers of progress in manned spaceflight than any decree from presidents or prime ministers.

(Note: this article subsequently appeared in Spaceflight magazine, July 2008, p.277-278.)

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(2) Celebrating (?) the Tunguska asteroid strike 100 years ago

Announcement from Andy Nimmo (Space Settlers' Society)

The Space Settlers' Society are planning to hold a meeting on Saturday 28th June in Glasgow, Scotland, at which we'll have talks on Tunguska (the 100th anniversary of which is on the 30th) and Apophis, the asteroid that'll pass Earth closer than geosynchronous orbit in April 2029, then close again in the mid 2030s, with discussion on what should be done about such things. This will be organized as a fund-raiser to assist Spaceguard UK getting a new camera set up. They need 65k and, while we may not raise all that, if we make a DVD of the event and sell this on the internet with all profit going to Spaceguard we may at least make some dent in the required sum.

Naturally we'll get the best speakers we can at our meeting and the DVD will also have lots of extra info on it about Tunguska and Spaceguard and its mission to protect our planet, along with lots of info about asteroids and comets, including the ESA, NASA, JAXA and other missions to Halley's Comet, Eros, Itokawa, etc.

If you'd like to come up to Scotland for the event or would like us to book you a copy of the DVD -- provisional sale price £15 -- please get in touch right away with Andy Nimmo of the Space Settlers' Society at (andynimmo -- at -- yahoo.com).

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(3) "Europe should give up on sending men and women into space" -- Martin Rees

According to the Astronomer Royal and President of the Royal Society, Lord Rees, manned space missions are largely irrelevant (thanks, David, for the reference).

He argues that Britain and Europe should abandon astronaut flights as a waste of money, and concentrate on robotic missions. In his words: "We in Europe should try and get a world lead in space exploration and applications".

Since one of the applications with greatest growth potential is space tourism, the learned lord would appear to be contradicting himself.

But he is, of course, merely repeating the party line that the only possible purposes for manned spaceflight and lunar and planetary exploration are science and prestige.

On the contrary: the immense untapped resources of space -- in terms of power, materials for construction and propellants, and human attraction as a leisure destination -- indicate that development of these resources could lead to a transformation of the global economy over the 21st century.

-- S.A.

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Astronautical Evolution is an e-mail forum devoted to debate and comment from an astronautical evolutionist perspective. To subscribe / unsubscribe / contribute / comment, please e-mail Stephen Ashworth, sa--at--astronist.demon.co.uk.

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