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The original Philip’s Chart of the Stars, first issued in 1940 under the editorship of the English schoolmaster Ernest Osborne Tancock (1886–1971), was for many years a staple fixture on the walls of amateur astronomers everywhere.

In 2018, Wil Tirion and I produced a new edition of this classic, with new maps and completely rewritten text and tables. As in previous editions, the chart is divided into a central section covering the equatorial region of the sky along with two polar hemispheres, thereby covering the entire night sky. The chart shows all stars visible to the naked eye under good conditions, and is usable from any latitude. Starting with this 2018 edition, the star names are those that have been officially sanctioned by the International Astronomical Union. As well as the descriptive text, the surrounding sheet contains tables of the 88 constellations, the brightest stars, double stars, variables, and deep-sky objects of interest to observers.

This new edition of the chart is intended for amateur astronomers, scouts, sailors, and anyone fascinated by the starry heavens. We hope it will serve them as well, and for as long, as did Tancock’s original.

A note on E. O. Tancock and the history of Philip’s Star Chart

Ernest Osborne Tancock (1886–1971) was a less-celebrated contemporary of another English schoolmaster-astronomer, Arthur P. Norton of Norton’s Star Atlas fame. It is highly likely that the two men knew each other through the British Astronomical Association, to which they were both elected in 1910.

Born in Norwich, Tancock was educated at Tonbridge School in Kent, coincidentally not far from the Judd School where Norton would later teach geography and mathematics. After graduating from Cambridge University in 1908 Tancock became a schoolmaster at Giggleswick School in Yorkshire. It was there that he wrote an introductory book called The Elements of Descriptive Astronomy, first published in 1913 by the Clarendon Press (now the Oxford University Press). A second enlarged edition appeared in 1919 and went through three reprintings, all published by Clarendon. A largely rewritten version of the same book was published by Philip’s in 1951 under the title Starting Astronomy.

Tancock seems not to have written any other books, nor published any papers or articles, although he did contribute a chapter on star identification to the book Astronomy for Everyman, edited by Martin Davidson (1953).

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The original cover of the Chart of the Stars, current from 1940 to 1961. In those days, the apostrophe in the name Philip’s was printed after the final letter s, not before.
Tancock edited the original Philip’s Chart of the Stars, first published in 1940 during World War II. It went through several reprints under Tancock’s name over more than 40 years. As well as the standard fold-out version, available either on paper or linen, it was sold on rollers for hanging on a wall. No doubt many people referred to the chart during the wartime blackout when stars shone undimmed by artificial lights. Stars down to 5th magnitude were plotted, although brightness estimates were not so accurate in those days so the cut-off at the fainter end was somewhat uneven. Accompanying the star charts were descriptive notes plus tables of the Greek alphabet, signs of the zodiac, first-magnitude stars, easy double stars, the brightest variable stars, and selected star clusters and nebulae.

Philip’s Chart of the Stars became widely popular and soon established itself as the standard wallchart for astronomers and anyone else interested in the sky, in much the same way that Norton’s Star Atlas was the standard atlas. It is remarkable to think that in the mid 20th century two modest English schoolteachers had come to dominate the international market for astronomical charts.

Unlike Norton, though, Tancock did not draw his own charts. Rather, they were the work of The London Geographical Institute, a division of the map publishers George Philip and Son. The first edition charts were rather crudely drawn and printed and have a distinctly wartime feel to them. A revised edition appeared in 1943 with minor changes to the text, most notably an expansion of the list of star clusters and nebulae, along with various improvements to the charts that included repositioning of a number of stars, Polaris among them, the inclusion of more deep-sky objects, and amendments to the outline of the Milky Way. The addition of a table of star names used by airmen suggests an attempt to extend its appeal to navigators.

In 1957 the Philip’s cartographers redrew the charts for a new edition. Tancock made minor revisions to the tables and expanded the text on using the chart. In 1961 the method of folding the map was changed and an illustrated cover was introduced, replacing the original midnight blue design shown above, but the content remained the same.

The epoch of the charts was not stated on either edition, but the (sometimes inaccurate) star positions in the first edition appear to be for 1900, while those for the 1957 edition are for 1950, which was the standard epoch at the time. This second edition of the chart was last reprinted in 1984, thirteen years after Tancock’s death but still bearing his name. It was the last printing to do so.

By then, star charts for epoch 1950 were obsolete. Another drawback was that the chart contained non-standard constellation names such as Camelopardus for Camelopardalis, Piscis Australis for Piscis Austrinus, and the obsolete Argo Navis, as well as other archaic terminology such as the use of the term ’nebula’ for the Andromeda Galaxy, all of which betrayed its origins in an earlier generation. Clearly, the chart was no longer suitable for a modern audience. In 1990 an epoch 2000 edition, now simply called Philip’s Star Chart (rather than Chart of the Stars), was produced by John Cox and Richard Monkhouse, accompanied by new text and tables. More stars were shown, down to 6th magnitude, and constellation boundaries were introduced for the first time. This chart was replaced in 2005 by an improved Wil Tirion version, which in turn was superseded by the all-new edition by Tirion and Ridpath of 2018.

The case of the missing mast
The first edition of the Philip’s Chart of the Stars showed a southern constellation called Malus, the mast (below left). This had been suggested in 1844 by John Herschel as a subdivision of the ancient Greek figure Argo Navis, the ship of the Argonauts. Herschel intended Malus to replace an invention of the French astronomer Nicholas Louis de Lacaille called Pyxis, the compass, but his proposal gained little support, and Pyxis rather than Malus was adopted by the International Astronomical Union in its list of 88 official constellations in 1922. Hence its inclusion on the Philip’s chart of 1940, along with the name Argo Navis, was an anachronism.
When the chart was redrawn in 1957 the name Malus was replaced by Pyxis (below right), although the label for Argo Navis remained. Note also various differences in the linking lines between stars, as well as some additional labelling on the newer chart and the inclusion of two additional star clusters, M41 in Canis Major and M46 in Puppis.
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The Astroglobe

One other rather curious item that bears Tancock’s name was a device called the Astroglobe, a form of celestial globe devised in conjunction with the engineer Kenneth Neal Monro (1879–1952). Monro and Tancock received a provisional patent for it in 1935 and the globe was produced for sale by Philip’s before World War II. An example of it is held by the Science Museum in London.

According to a review in the Journal of the British Astronomical Association in 1936, the Astroglobe consisted of a glass sphere which could be half-filled with a coloured liquid to represent the observer’s horizon. The equator, ecliptic, and main star groups were depicted on the globe’s surface. ’All the simpler problems of spherical trigonometry can be solved graphically by this globe,’ the review stated. The Astroglobe seems to have been inspired by Tancock’s simple model of the celestial sphere that was described and illustrated in his book The Elements of Descriptive Astronomy.

A brief obituary of Tancock was published in the Journal of the British Astronomical Association in 1972. Although Tancock become a Fellow of the Royal Astronomical Society in 1919 (something that Norton never did), and was still a member when he died, he seems never to have received an obituary notice from them.