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Book review: Haynes manual – Saturn V

W. David Woods (2016). NASA Saturn V – 1967-1973 (Apollo 4 to Apollo 17 & Skylab) – Owner’s workshop manual – An insight into the history, development and technology of the rocket that launched man to the Moon. Haynes Publishing, Yeovil, Somerset. ISBN 978 0 85733 828 0. Hardcover, 27.2×20.8×1.4 cm. 172 pages, several photos or illustrations per page. £22.99 rrp.

ASE members will recall the author’s fascinating talk on how Apollo flew to the Moon. He has written other books on spaceflight, including co-authorship of the Haynes manuals on Gemini and the Lunar Rover. About 50 years after NASA settled on the Saturn IB and V designs as carrier for the Apollo programme, Woods places this iconic machine centre-stage and makes the engineering the story itself.

The first chapter deals with the history leading up to the Saturn rocket, not least Wernher von Braun and the German A-4, which under its belligerous assignation “V2” inflicted tens of thousands of casualties among the British population and the slave labourers that were forced to build it. Originally interested in spaceflight for its own sake, von Braun was again lead figure when NASA made spaceflight a civilian project again.

The main chapters deal with the rocket from the bottom up. The F1 engine is described in good and consistent detail. This is followed by the chapter about the S-IC stage – the first stage of the Saturn V and powered by five F1 motors. Description of the J2 engine is a bit shorter due to similarities with the F1. Both the second S-II stage and the third S-IVB stage are powered by five and one J2 motors resp. The bulk of the volume and mass of the rocket is necessarily in the tanks for liquid oxygen and fuel (kerosene in the S-IC and liquid hydrogen in the S-II and S-IVB). The IU instrument unit atop the third stage is given its own chapter as the brains of the rocket.

The penultimate chapter draws it all together and takes us through an average flight from launch to lunar transit injection and final disposal of the third stage. The average flight was not without complications, and so a variety of real flights serve to illustrate the problems that did occur on occasion.

The final chapter is about Skylab, which seems strange at first. The book otherwise refrains from speaking about the Apollo missions after the S-IVB had done its job and was usually orbiting the Sun or had crashed into the Moon. Launching the space station (without crew) was the last flight of a Saturn V. But also, Skylab itself was a modified S-IVB and in that sense part of the last Saturn V to fly.

It is fascinating to learn in some detail how these rocket motors work. There is elegance in the design, for example how the propellants are used to lubricate, and to drive the turbo pumps that then pump those same propellants to the combustion chamber. I was surprised that the iconic bell shape of the rocket motor nozzles is not solid metal cast or shaped from sheets, but is merely a collection of hundreds of parallel tiny metal pipes bonded together to make the shape required for best performance as an exhaust nozzle. One of the propellants is fed through these pipes down the nozzle wall and back up, both to cool the nozzle and to warm up the propellant, or even evaporate the liquid hydrogen prior to combustion.

The book has a lavish collection of high quality photographs and purpose-made drawings and diagrams, which make good use of colour. It does not so much work as a picture book, the text and pictures go together and match closely. Still, some diagrams illustrate more than the point in hand, such as the plot of g-force versus time into the rocket flight, which also illustrates how short the first-stage flight is compared to the second stage. In the text the level of detail is good and consistent.

There are a variety of technical terms used in the Saturn V programme. Some sound serious like “max-Q”, others may confuse like the two-page lecture on specific impulse in relation to weight and mass, resp. Others are refreshingly intuitive like the “pogo phenomenon” that could make astronauts very uncomfortable at times.

Should you wonder at the end, why some Apollo flights are hardly mentioned – Apollo 7, the three Skylab crew flights and the Apollo-Soyuz rendezvous – this is because they flew on the lesser, two-stage Saturn IB, which was sufficient to reach Earth orbit. Saturn V was all about the Moon, even if not much of the rocket itself reached the Moon. Some of its third stages flew by the Moon to enter solar orbit, others were crashed into the Moon to be monitored by seismometers already in place.

Horst Meyerdierks

Horst is currently Secretary of the Astronomical Society of Edinburgh and was the Journal’s previous editor, prior to it’s online incarnation.
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Solar Eclipse 2015 – Members’ Experiences

The various stages of the eclipse – deepest eclipse top, right and last contact bottom, right. (Photo: Horst Meyerdierks)

The solar eclipse of 2015-03-20 was total in the North Atlantic, with the path of totality crossing the Faroe Islands and Svalbard. In Edinburgh, the eclipse was partial with 94% of the solar diameter covered by the Moon at deepest eclipse. The weather forecast was not good, but slightly better for Angus and Northumberland. The afternoon before, I decided to drive to Angus, but at 04:15 on the morning of the eclipse I checked the forecast and changed plan. At 05:10 I headed to Northumberland, where the eclipse would be 92%. Stopping between Wooler and Morpeth, the weather seemed better further inland and I first settled for a spot between Thropton and Harbottle at 07:30.

However I decided to explore further up the road, and by the time I came back at 08:00 it was too cloudy. I decided to try further south, but by the time I reached the main road I changed my mind again and went for the blue sky to the Northeast. At 08:36 – five minutes after first contact, I finally settled for a field track outside Bolton near Alnwick. Before setting up, I tried to take a few free-hand shots at 200 mm focal length. But I lost them in a memory card reformat and had to take one more on the refreshed card. Also, I messed up and left the lens at 55 mm focal length instead of turning it to 200 mm. By the time I had set up the telescope and took the first proper image, it was 08:55, the phase already 39%.

Solar imaging set up

The solar imaging equipment set up and ready to use. (Photo: Horst Meyerdierks)

There was varying cloud in front of the Sun; mostly I used a foil filter, but at times I used the cloud as only filter. I am still a bit annoyed, because the sky in general was reasonably clear. A spot a few km away might have had better weather, and at home -as it turned out – people saw the eclipse as well. But the weather forecast was particularly tricky and ultimately meaningless that day, and I tried to be sure of the best chance of seeing the eclipse.

The images at the top of the article were taken with a VEB Carl Zeiss Jena Telementor II refractor (63 mm aperture, 840 mm focal length, f/13.3), Baader foil filter, and Canon EOS 600D camera (pictured above). The second and fourth image show the deepest eclipse and the last contact. I am grateful to have this telescope, which I got through the Astronomical Society of Edinburgh from a member of many years who is no longer able to make use of the scope. It is a perfect replacement for my previous solar imaging setup. The optical quality is outstanding – as good as optical theory will permit – and the mount is very sturdy for its size, weight and load. Being entirely manual, the mount is ideal for this sort of project.

The media constantly compared this eclipse with 1999 as the last major eclipse. In fact, the 2003 eclipse was deeper at 98%, the 1999 eclipse was only 86% in Edinburgh. UK-wide, 1999 and 2003 would have been about the same depth, one being total in Cornwall and the other annular in Caithness.

Horst Meyerdierks

This is one of a series of personal accounts recorded by our members of their experience viewing the partial solar eclipse on the 20th of March 2015.

It’s Not Over Until The Fat Planet Shines!

Peter and I concluded this must be our fourth evening at the Royal Botanic Garden John Hope Gateway Centre. But this time it was not an astronomy event per se, but a coming together of art and science, and a preview of the Sea Change exhibition on 2013-11-07.

As on previous occasions, we would set up on the terrace outside the restaurant. Graham Rule had taken large binoculars and tripod on the bus, while Peter Mulholland and I brought very similar small refractors on identical mounts. And John Wood had just got hold of the ASE’s 250 mm Schmidt-Cassegrain that he still needed to get used to.

The day had been clear and sunny, but after dark it turned cloudy and rainy. While Graham was already checking the Balmoral Hotel clock through the binoculars, we reluctantly set up the scopes – under the roof where they would stay the whole three hours due to regular spells of rain. Some time into the event we could identify Auriga, Cygnus and Vega. Peter trained his goto computer and later kept tracking the clouds in front of the Pleiades. We did see the star cluster in binoculars and toward the end also as star map on an Android screen.

11001c

Not many people therefore ventured out into the dark and cold; mostly we could only show some leaves on trees across the pond through two telescopes. Some interesting conversations were had, but the weather made this an almost complete washout. Having fulfilled our duty we packed up at 22:00. Last was the SCT with tripod and tube already detached. When Jupiter not only split the cloud but also found a gap between the trees. While John and Graham still tightened the bolts that keep the scope on the tripod I swung the tube to acquire the giant planet in the finder and in three minutes we were looking at the Galilean moons and Jovian cloud bands. A few of the guests and staff were also still around to get a view during gaps in the cloud.

It is of course common for planned observing meetings to be clouded out, whether that be ASE members meeting in a park or an outreach event like this. At least there is good company and the effort is appreciated by the hosts and budding observers.

Horst Meyerdierks

ASE Journal – Old and New

It’s good to see the ASE Journal again! There is a saying in German: “trust no one over thirty”; perhaps that is why the Journal took a break in 2010. Dave Gavine started the Journal in August 1980, and there is a full account in my 2008 article [1].

Journal 3, October 1981

Journal 3, October 1981

As you can see, in the early days, the best images were the ones you drew yourself. There were hardly any computers and no laser printers in 1980; photocopiers were no good for half tone images and colour copiers were the stuff dreams were made of.

The Journal came to a pause in 2010, in reality, because I was drafted in as Secretary. Discontinuing the Journal allowed me the time required for the new tasks.

The Journal has been online since 1998, and the older issues were digitised in 2008. Find them all at [2]. However, making a good online copy and a good paper copy is quite a challenge. Now that people have multi-core, GHz computers in their pocket at all times, perhaps we can get away without a paper copy!

References:

  1. Horst Meyerdierks (2008). “28 years of ASE Journal – now online”. ASE Journal, 56. http://www.astronomyedinburgh.org/publications/journals/56/journal.shtml
  2. ASE Journal, http://www.astronomyedinburgh.org/publications/journals/

Horst Meyerdierks