Monthly Archives: November 2016

The Big Bang: who first suggested it?

The phrase ‘Big Bang’ was coined in 1949 by astronomer Fred Hoyle as a label for a cosmological model of the universe, although one with which he happened to disagree. However, the theory itself had an earlier origin.

Many think that George Lemaitre, a Belgian Roman Catholic priest, astronomer and professor of physics at the Université Catholique de Louvain was the first to suggest cosmic expansion. In his 1927 report, ‘A homogeneous universe of constant mass and growing radius accounting for the radial velocity of extragalactic nebulae’, he proposed that the universe expanded from the finite static state imagined by Einstein. But only in 1931, at a meeting of the British Association on the relation between the physical universe and spirituality (sic), did he propose that the universe originated in a ’primeval atom’ (but this was 2 years after Edwin Hubble had demonstrated cosmic expansion).

Many think it was mathematician Alexander Friedmann who, unknown to Lemaitre, proposed a similar solution to Einstein’s equations in 1922.

However, what seems to be little known is the fact that both Friedmann and Leamaitre were forestalled by the American writer and poet Edgar Allan Poe.

Edgar Allan Poe

In 1848 (79 years before Lemaitre and 74 years before Friedmann), he wrote Eureka: A Prose Poem, also subtitled ‘An Essay on the Material and Spiritual Universe’. It was his last major work and his longest non-fiction work at nearly 40,000 words. It was based on a lecture he gave on the 3rd of February 1848 in the Society Library in New York entitled ‘On The Cosmography of the Universe’. He died the following year.

Poe dedicated the work to Alexander von Humboldt, whose book Kosmos he must have read, at least the first two volumes. It was Humboldt who coined the word ‘cosmos’ (from the Greek kosmos) in the sense that modern cosmology uses it, to describe everything that exists in the universe, or the universe itself. In the volumes Poe must have read, he examined what was then known of the Milky Way, cosmic nebulae, and planets. The first volume was so popular that it sold out in two months.

Eureka describes Poe’s intuitive conception of the nature of the universe with no reference to any scientific work done to reach his conclusions (well there were none). His general proposition was ‘Because Nothing was, therefore All Things are’.

That is a bit vague, but it seems to suggest that the universe came out of nothing! Hasn’t modern science come to that conclusion? Indeed, he proposed that it had an origin: Poe contended that the universe filled with matter after a single, high-energy particle exploded and that, since the energy of the explosion is pushing matter outward, the universe must be expanding.

A reviewer in the New York Review of Books in February last year observed that [1]:

‘This by itself would be a startling anticipation of modern cosmology, if Poe had not also drawn striking conclusions from it, for example that space and ‘duration’ [i.e. ‘time’] are one thing, that there might be stars that emit no light, that there is a repulsive force that in some degree counteracts the force of gravity, that there could be any number of universes with different laws simultaneous with ours, that our universe might collapse to its original state and another universe erupt from the particle it would have become, and that our present universe may be one in a series.’

Apart from suggesting a Big Crunch, Poe was the first to explain Olbers’ Paradox (the night sky is dark despite the vast number of stars in the universe); I wrote about this in the Journal 8 years ago [2]. Poe claimed, as many do now, that the universe is not old enough to fill the sky with light. The universe may be infinite in size, he thought, (we think that now don’t we?) but there hasn’t been enough time since the universe began for starlight, travelling at the speed of light, to reach us from the farthest reaches of space. A Wikipedia page on the Paradox recognises Poe’s priority in this matter.

Response to Eureka was overwhelmingly unfavourable and the lecture on which it was based received negative reviews such as ‘hyperbolic nonsense’, but one newspaper called in ‘a noble effort’. Many were bored by the lecture which evidently was too long and rambling. However, Poe considered Eureka to be his masterpiece. He believed that the work would immortalize him because it would be proven to be true. Indeed, much of what he claimed has been verified and some, like Arthur Eddington, praised it. Albert Einstein called it ‘a beautiful achievement of an unusually independent mind’. 

Eureka was published in a small hardcover edition in March 1848 by Wiley & Putnam priced at 75 cents. Poe persuaded George Putnam, to publish Eureka after claiming the work was more important than Isaac Newton’s discovery of gravity (Newton did not discover gravity, but he did explain it)! Putnam paid Poe $14 (3-4 hundred dollars today) for the work. Poe suggested an initial printing of at least one million copies, but Putnam settled on 750, of which 500 were sold that year.

The book can still be bought in various editions and it can also be read online [3]. The National Library of Scotland has two copies, one of them the original 1848 edition, apparently once owned by the poet Dante Gabriel Rossetti.

What Poe suggested in this inspired work, with no antecedents, except perhaps Humboldt, is astonishing in its prescience. He deserves more recognition for his insights.

Finally, Poe has a Scottish connection. He was briefly at school in Irvine in 1815 when the Allans, his foster family, visited Britain. Let’s celebrate him.

References:

      1. The New York Review of Books, February 5, 2015 – “On Edgar Allan Poe” by Marilynne Robinson
      2. ASE Journal No. 57, September 2008 – “Why is it dark at night?” by Steuart Campbell
      3. Eureka by Edgar Allan Poe, 1848. For an analysis of the work, see Eureka, an annotated edition by Stuart and Susan F Levine, University of Illinois Press, 2004.

Steuart Campbell

This article is based on an illustrated talk given to the ASE by Steuart Campbell on 4 November 2016. Steuart is a member of the ASE and a regular contributor to the Journal.
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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.

Scotland’s Sky in November, 2016

Nights begin with Venus and end at Jupiter

The maps show the sky at 21:00 GMT on the 1st, 20:00 on the 16th and 19:00 on the 30th. An arrow depicts the motion of Mars after the first week of the month. (Click on map to enlarge)

The maps show the sky at 21:00 GMT on the 1st, 20:00 on the 16th and 19:00 on the 30th. An arrow depicts the motion of Mars after the first week of the month. (Click on map to enlarge)

The end of British Summer Time means that we now enjoy six hours of official darkness before midnight, though I appreciate that this may not be welcomed by everyone. The starry sky as darkness falls, however, sees only a small shift since a month ago, with the Summer Triangle, formed by the bright stars Vega, Deneb and Altair, now just west of the meridian and toppling into the middle of the western sky by our star map times.

Those maps show the Square of Pegasus high in the south. The star at its top-left, Alpheratz, actually belongs to Andromeda whose other main stars, Mirach and Almach, are nearly equal in brightness and stand level to its left. A spur of two stars above Mirach leads to the oval glow of the Andromeda Galaxy, M31, which is larger than our Milky Way and, at 2.5 million light years, is the most distant object visible to the unaided eye. It is also approaching us at 225 km per second and due to collide with the Milky Way in some 4 billion years’ time.

Binoculars show M31 easily and you will also need them to glimpse more than a handful of stars inside the boundaries of the Square of Pegasus, even under the darkest of skies. In fact, there are only four such stars brighter than the fifth magnitude and another nine to the sixth magnitude, close to the naked eye limit under good conditions. How many can you count?

Mars is the easiest of three bright planets to spot in tonight’s evening sky. As seen from Edinburgh, it stands 11° high in the south as the twilight fades, shining with its customary reddish hue at a magnitude of 0.4, and appearing about half as bright as the star Altair in Aquila, 32° directly above it.

Now moving east-north-eastwards (to the left), Mars is 5° below-right of the Moon on the 6th and crosses from Sagittarius into Capricornus two days later. Soon after this, it enters the region covered by our southern star map, its motion being shown by the arrow. By the 30th, Mars has dimmed slightly to magnitude 0.6 but is almost 6° higher in the south at nightfall, moving to set in the west-south-west at 21:00. It is a disappointingly small telescopic sight, though, its disk shrinking from only 7.5 to 6.5 arcseconds in diameter as it recedes from 188 million to 215 million km.

We need a clear south-western horizon to spy Venus and Saturn, both low down in our early evening twilight. Venus, by far the brighter at magnitude -4.0, is less than 4° high in the south-west thirty minutes after sunset, while Saturn is 4° above and to its right, very much fainter at magnitude 0.6 and only visible through binoculars. The young earthlit Moon may help to locate them – it stands 3° above-right of Saturn on the 2nd and 8° above-left of Venus on the 3rd.

Mercury is out of sight in the evening twilight and Saturn will soon join it as it tracks towards the Sun’s far side. However, Venus’ altitude thirty minutes after sunset improves to 9° by the 30th when it sets for Edinburgh at 18:30 and is a little brighter at magnitude -4.1. Viewed telescopically, Venus shows a dazzling gibbous disk that swells from 14 to 17 arcseconds as its distance falls from 178 million to 149 million km.

Sunrise/sunset times for Edinburgh change from 07:20/16:31 on the 1st to 08:18/15:44 on the 30th. The Moon reaches first quarter on the 7th, full on the 14th, last quarter on the 21 and new on the 28th.

The full moon on the 14th occurs only three hours after the Moon reaches its perigee, the closest point to the Earth in its monthly orbit. As such, this is classed as a supermoon because the full moon appears slightly (7%) wider than it does on average. By my reckoning, this particular lunar perigee, at a distance of 356,509 km, is the closest since 1948 when it also coincided with a supermoon.

Of the other planets, Neptune and Uranus continue as binocular-brightness objects in Aquarius and Pisces respectively in our southern evening sky, while Jupiter, second only to Venus in brightness, is now obvious in the pre-dawn.

Jupiter rises at Edinburgh’s eastern horizon at 04:28 on the 1st and stands more than 15° high in the south-east as morning twilight floods the sky. It outshines every star as it improves from magnitude -1.7 to -1.8 by the 30th when it rises at 03:07 and is almost twice as high in the south-south-east before dawn.

Currently close to the famous double star Porrima in Virgo, Jupiter is 13° above-right of Virgo’s leader Spica and draws 5° closer during the period. Catch it less than 3° to the right of the waning earthlit Moon on the 25th. Jupiter’s distance falls from 944 million to 898 million km during November while its cloud-banded disk is some 32 arcseconds across.

The annual Leonids meteor shower has produced some stunning storms of super-swift meteors in the past, but probably not this year. Active from the 15th to 20th, it is expected to peak at 04:00 on the 17th but with no more than 20 meteors per hour under a dark sky. In fact, the bright moonlight is likely to swamp all but the brightest of these this year. Leonids diverge from a radiant point that lies within the Sickle of Leo which climbs from low in the east-north-east at midnight to pass high in the south before dawn.

Alan Pickup

This is a slightly-revised version of Alan’s article published in The Scotsman on November 1st 2016, with thanks to the newspaper for permission to republish here.