There does not seem to be any reason why it should not be possible, by the use of a suitably designed multi-stage rocket, to send a projectile into space beyond the Earth’s gravitation. From the scientific and engineering points of view, interplanetary travel may be considered to be a practical possibility. It is the great expenditure of money and the tremendous demands on man-power which it would involve that will delay its achievement. The enthusiasts say that it could be done in ten years; but the problems to be investigated and to be solved are so many and so varied that I am inclined to give a much more cautious estimate and to say that half a century would not be an unduly long time.

Sir Harold Spencer Jones, Astronomer Royal, in the Foreword to Across The Space Frontier (1952)

Across The Space Frontier is an expanded version of a series of articles published in  Collier’s magazine on March 22, 1952, under the title “Man Will Conquer Space Soon”. You can find the original articles on-line, courtesy of the American Institute of Aeronautics and Astronautics, Houston Section, who reissued  the Collier’s articles in their Horizons newsletter of July/August 2012 (22.5MB pdf). The Horizons archive is here, and if you’re interested in these classic articles, you should look through the next seven Horizons issues (up to September/October 2013) too, because they include subsequent Collier’s articles on a variety of spaceflight-related topics.

The book was written in the very earliest days of America’s space programme—an operation at that time based mainly around captured German V2 rockets and German rocket scientists brought to the USA at the end of the Second World War by Operation Paperclip.  At the time of writing, the first artificial satellite was still five years away; the unmanned altitude record was a mere 393 kilometres, achieved by the two-stage Bumper-WAC, essentially a sounding rocket attached to the top of a V2; and the human altitude record was 24,230 m, achieved by test pilot Bill Bridgeman in a Douglas Skyrocket aircraft.

At the core of the book is Wernher von Braun’s vision of how space exploration would proceed over the next decade or so, beautifully illustrated by Chesley Bonestell’s iconic paintings. Willy Ley contributes an article on the concept of a rotating space station. and there are essays by other contributors on topics as diverse as the physiology of space travel, the legal issues which might be raised by space exploration, and the astronomical benefits of siting an observatory in space.

What is interesting about this work, in the present day, is to compare the vision with the subsequent reality. The rocketry is not too much different: von Braun’s design for a conical three stage launch vehicle was 265 feet high and 65 feet wide at the base, compared to the Apollo missions’ cylindrical Saturn V, which was 363 feet high and 33 feet wide. Von Braun’s ferry rocket weighed an estimated 7000 tons and would deliver 36.5 tons to orbit, while the Saturn V weighed 3270 tons and delivered 155 tons to orbit. These differences are probably accounted for by structural economies and improved rocket technology—von Braun’s concept rocket was launched using fifty-one rocket motors powered by a mixture of hydrazine and nitric acid; the Saturn V rose into the air supported by just five huge rocket motors running on kerosene and liquid oxygen.

Von Braun mentioned two possible launch sites for his rockets—Johnston Island in the Pacific, and the Air Force Proving Ground at Cocoa, Florida. The former is the one used in the book illustrations and examples; the latter turned into what we know as the Kennedy Space Center.

But Apollo-era technology diverged strongly from von Braun’s vision in other respects—von Braun envisioned incremental progress into space, consolidating at each step; whereas Apollo turned into a race to get to the moon quickly. So all the stages of von Braun’s planned rocket were recoverable and reusable—the first and second stages parachuting back into the ocean, the third stage sporting wings and returning to Earth as a glider, like the Space Shuttle. The goal of initial launches was to deliver construction materials to low Earth orbit, for the construction of a large rotating space station of the sort depicted in 2001: A Space Odyssey. A mission to the moon would then be launched from the space station, delivering a huge multi-storey lander with the intention of setting up a permanent moon base. Instead, Apollo used disposable rocket stages and shot straight for the moon with a tiny and extremely fragile lander.

Ley’s description of a rotating space station is detailed and fascinating, and the only one I’ve seen that takes into account the  real necessity for careful control of the centre of mass of the structure, to avoid wobbling.

For all I love Bonestell’s space art, my favourite painting in the book is by Rolf Klep, who provided an illustration of a space-suited figure, using a small rocket motor to propel himself around the space station. Clearly visible through the helmet visor, the astronaut is sporting a pair of spectacles. Evidently, the initial exploration of space was envisaged as being a task for stereotypical scientists, not the perfect physical specimens who actually ended up doing the job.

The Mars Project was written by Wernher von Braun, and was originally published in German as Das Marsprojekt (1952). The University of Illinois had it translated by Henry J. White and first published it in English in 1953, with repeat editions in 1962 (when von Braun wrote a new preface) and in 1991 (when NASA Administrator Thomas O. Paine added a foreword). It formed the basis of an illustrated Collier’s article “Can We Get To Mars?” in the April 30, 1954 edition. The Collier’s article was reproduced in the September/October 2013 edition of the Horizons newsletter of the American Institute of Aeronautics and Astronautics, Houston Section. You can download a pdf (6MB) of the relevant newsletter from their archive, and it’s well worth a look for its gorgeous artwork alone.

The Mars Project is a very different beast from Across The Space Frontier. Whereas the latter was aimed at a lay readership, The Mars Project is a technical publication, full of tables, equations and charts. In his spare time, and with his trusty slide-rule, von Braun set out to prove that it was possible to travel to Mars using the known technology of the 1950s. Having worked through the necessary celestial mechanics and rocketry, he concluded that:

… the logistic requirements for a large, elaborate expedition to Mars are no greater than those for a minor military operation over a limited theater of war.

His vision involves the assembly of ten 4000-tonne spacecraft in Earth orbit. Getting the material to orbit would require 950 launches of the “ferry rockets” described in Across The Space Frontier. Because his ferry rockets are fully recoverable, he imagines using 46 of them, with a 10-day turnaround between recovery and launch, to get all the necessary equipment into orbit in just eight months!

His giant interplanetary spacecraft, each about the height of the Statue of Liberty, then set off towards Mars, carrying a total crew of 70. His fuel calculations are based on  hydrazine/nitric acid propellant—but by the time he wrote his 1962 preface, he was pointing out the advantages of liquid hydrogen and oxygen. His calculations concerning the necessary transfer orbits are still valid today, and he correctly pointed out that his astronauts would need to spend more than a year on Mars, waiting for the planetary positions to fall into the correct alignment for their return journey.

Only when he gets us to Mars do his assumptions become invalid. According to the astronomy of the day, Mars’s atmospheric pressure was about 1/12 of Earth’s (we now know it’s only 0.6%). So von Braun is able to get his astronauts to the surface in winged rocket-planes with landing speeds around 200 kph, which can be cranked upright at the end of the mission to return to orbit as conventional rockets. If only Mar’s atmosphere were really that dense! We could have avoided all those awkward parachute/rocket/crane combinations that have actually been needed to get probes safely down to the surface of Mars.

One of the most astonishingly ambitious concepts, in a book full of astonishingly ambitious concepts, is the arrival on Mars. Von Braun imagines his astronauts taking their first landing boat down to the Martian polar ice-cap:

Considering the risk attending a wheel landing on completely strange territory at relatively high speed, it is assumed that the first landing boat will make contact with the Martian surface on a snow-covered polar area, and on skis or runners, minimizing this risk.

And then:

With [ground] vehicles, the crew of the first landing boat would proceed to the Martian equator and there select or prepare a suitable strip for the wheeled landing gears of the remaining two boats.

Yep, that’s just a 5000-kilometre jaunt across “completely strange territory”, with all the gear required to stay alive on the way and build an airstrip when you get there.

This is a fascinating book, if you enjoy watching a clever man caught pretty much in the act of inventing astronautics, and don’t mind a lot of tables and equations. My only criticism of the University of Illinois’s most recent edition is that they didn’t take the chance to harvest more of the gorgeous paintings used in the Collier’s article. The only one on show is Chesley Bonestell‘s Mars-bound Spaceship Flotilla, which features as the cover art.