Zdenĕk Kopal Papers

Archive Collection

Scope and Content

Zdenĕk Kopal made a number of crucial discoveries in astrophysics which locate him in history as one of the founding fathers of modern astrophysics. His work around the study of the development of closely neighbouring stars, known as close binaries, ranks with the most important developments in astrophysics of the 20th century.

Kopal's personal archive provides detailed information about his lifetime of research and his various roles within and contributions to the international astronomy community. His papers cover almost the entire span of his professional career from the 1940s until his death. However, relatively few papers survive from the earlier part of his life in Czechoslovakia; his period at Harvard and MIT is mostly represented by his research notebooks.

The majority of the collection comprises Kopal's correspondence and subject files (KOP/1), which he accumulated from his time as professor of astronomy at the University of Manchester. It is evident that Kopal and his secretary took some care to create and preserve files which documented his diverse activities. These files will typically include some major projects and research work, but there are also many files relating to his publications, his editorship of scientific journals, and his involvement with professional bodies such as the International Astronomical Union. The content of these files usually comprehensively covers the subjects in question.

The correspondence files are in nearly all cases organised either as general correspondence or by subject, and there are virtually no files organised by individual correspondents. There are often several files organised chronologically relating to professional and research bodies such as the International Astronomical Union, International Academy of Astronautics, and International Astronomical Federation, the Royal Astronomical Society, the Royal Society, COSPAR, and NASA. In addition, there are files concerning specific projects Kopal was involved with, primarily the Manchester Lunar Programme: Pic-Du-Midi Observatory, US Air Force, European Office for Aerospace Research and Development. and the American Chart and Information Center, but also the Jet Propulsion laboratory, Pasadena, the Lunar Planetary Institute, Houston, Boeing Scientific Research Laboratories, and the Jungfraujoch High Alpine Research Station, Switzerland,

Kopal also kept detailed records of various conferences attended and lectures delivered, as well as his correspondence with publishers concerning his books. There are individual files relating to the publishers, Academic Press, Reidel, Elsevier, Adam Hilger, Pergamon, McGraw Hill, Faber and Faber an North Holland Publishing oc. amongst others. These provide interesting sidelights on the relations between academic scientists and publishers in this period. There are also numerous files relating to Kopal's editorship of Earth, Moon and Planets andAstrophysics and Space Science, dating from the late 1960s to the early 1990s. These contain a wealth of detail about astronomical and astrophysical research published in these publications, as well as more generally about opinions and ideas within these research communities.

There are a number of individual files relating to conferences and seminars which Kopal spoke at including those of the IAU. Other files relate to more particular connections of Kopal, including his long-standing links with observatories at Helwan, Egypt, Assiago,Italy, Nizamia, India and Kwasan, Kyoto, Japan.

Kopal also organised his professional correspondence into files of general correspondence, and these are less straightforward to interpret. Files were maintained for a period of several years and organised alphabetically; this seems to have been his preferred method of arranging academic and professional correspondence from the early 1950s until his retirement in 1981. However, it also appears that Kopal kept chronologically overlapping files of correspondence, with no clear demarcation to indicate why some correspondence was kept in particular files covering the same period. Hence correspondence with the same individual may occur in different 'general' files as well as subject-specific files. Some of these 'general' files relate more to his work as head of department at Manchester, but they are not confined to this subject matter.

Kopal's research notebooks (KOP/2) focus on his US research and work on eclipsing binaries during the 1950s; there is comparatively little information on the lunar mapping programme, probably because he did not conduct this research in the same manner. Much of the content of the notebooks is highly technical and mathematical in nature.

Kopal was a prolific author, co-author, editor or co-editor of more than 30 books and 400 journal articles. The archive therefore includes many draft copies of articles and book chapters. (KOP/3)> these are mostly typed, with occasional comments and amendments in holograph by Kopal. Most of these drafts date from the 1960s to the 1980s. In addition, Kopal kept a collection of his article offprints. This is not complete, and probably contains less than half of his published output (KOP/4); again, some of these offprints have been annotated by Kopal.

The series of USAF contracts (KOP/5) relates primarily to the lunar mapping map, and is essential to understanding how the project was conducted. Apart from the formal contracts for different aspects of the project

Kopal's pears contain relatively few personal or family items. He appears to have accumulated only a modest collection of cuttings, mostly relating to his publication (KOP/6). The archive contains a small number of Kopal's own photographs, many of which show astronomical observatories, an area of interest to Kopal; this can be found in KOP/7.

The Kopal archive also includes glass negative and print photographs taken as part of the Manchester Lunar Programme, as well as various research data from this project; this material is uncatalogued, and there is currently no inventory of contents. In these circumstances, this uncatalogued material will not normally be made available for consultation.

Administrative / Biographical History

Zdenĕk Kopal was a Czech-born astronomer and astrophysicist, who made notable contributions in several areas of optical astronomy and stellar astrophysics, especially binary stars and lunar topography.

Kopal was born on 4 April 1914 in Litomy l, Bohemia, Austria-Hungary (now in the Czech Republic). He was interested in astronomy from an early age, and had already had a scientific paper published before he went to university.

Kopal studied physics at the Charles University, Prague (B.S., 1934; D.Sc., 1937). He then continued his research at the University of Cambridge and Harvard University. At Cambridge, Kopal worked with Arthur Eddington (1882-1944), the celebrated English astronomer, physicist, and mathematician, before moving to the USA. Here he was a research fellow at Harvard Observatory from 1938 to 1940, and later a research associate in astronomy at Harvard University, 1940-46. During the War he worked with the US Navy on ballistics research, where his mathematical expertise was put to good use. After the War, he lectured Massachusetts Institute of Technology from 1947 to 1951.

Kopal's early research was in two areas: mathematical numerical analysis, which drew in part on his wartime work, and led to the publication of Numerical Analysis (1955), which became the standard text for the subject. However, his most important area of research was the study of close binary stars, where he became an international authority.

Kopal was most at home with scientific questions that were clearly defined and amenable to mathematical treatment. With close binaries he used these skills to investigate the apparently paradoxical phenomenon of less massive stars evolving more rapidly than their massive neighbours. Kopal produced incontrovertible evidence that in many paired stars, the lighter star has the larger radius and therefore would be considered more evolved. This star had in effect 'spilt' material into its less-developed neighbour, increasing the latter’s mass.

In 1951, Kopal was invited to England to head the new astronomy group at the University of Manchester. Astronomy had not been an important subject at the University, but the then head of the department of physics, Patrick Blackett, was keen to advance the subject. Kopal’s optical astronomy group complemented the larger radio-astronomy group led by Bernard Lovell, and both groups operated essentially as sub-departments of the main department of physics. It is a tribute to Kopal’s leadership that by the time he retired from the University in 1981, his department had an international reputation and had not been eclipsed by the radio-astronomers at the Jodrell Bank Observatory.

At Manchester, Kopal initially continued his research on close binary stars, working closely with mathematicians to devise models to explain the “evolutionary paradox” of the expanding star in a binary system losing mass to its initially less developed pair. This culminated in the publication of Close Binary Systems in 1959. During the 1950s, Kopal’s research team had also been working on photometric techniques for the study of distant celestial light sources. This had involved using photographic equipment at European observatories such as the Jungfraujoch in Switzerland, Assiago in Italy and Pic-du-Midi in the French Pyrenees.

This work along with his acquaintance with the American chemist, Harold Urey, while researching at the University of Wisconsin in 1957, was to see a major reorientation of Kopal’ work for the next fifteen years. Kopal already had an interest in solar system astronomy, but Urey, who was bringing modern chemical and physical ideas to the study of the solar system, awoke Kopal’s interest in lunar studies. This coincided with the opening of the Space Race, and it soon became evident that this would involve direct study of the Moon’s surface, initially by probes, but eventually by human landings on the Moon. Exploration in this manner would require a much better understanding of the Moon’s topography, and the creation of accurate, detailed lunar maps became a priority. Kopal was commissioned by the US Air Force to provide photographic studies of the Moon’s surface, which would be used for these more detailed maps. This was beginning of the Manchester Lunar Programme, which absorbed Kopal’s energies until the late 1960s.

The Programme was an ambitious project to photograph the Moon's surface in unprecedented detail using the facilities at the Pic-du-Midi Observatory. At its height, the MLP had over fifty people working at the Observatory, and between 1960 and 1967 over 60,000 photographs were taken on 9 inch films. Each day, researchers would start photographing the Moon at sunrise, and a sequence of photographs was taken which would track changes in the lengths of shadow of various points as the Sun passed over the Moon's surface. Data from these photographs was then used to calculate differences of altitudes of the Moon’s surface to a high degree of accuracy by the American Chart and Information Center, a USAF-affiliated body, based in St Louis, Missouri. The lunar mapping increased scientific understanding of the Moon and encouraged research in other areas, including selenodesy and lunar geology. Kopal was involved in the ‘Space Race’ in other capacities, working as a special consultant to NASA, the Jet Propulsion Laboratory in Pasadena, California, and at the Boeing Research Laboratories.

Kopal exploited the huge public interest in the Moon by publishing a number of academic and popular works including, The Moon: our nearest celestial neighbour (1960), The Physics and Astronomy of the Moon (1962), An introduction to the study of the Moon (1966), The Moon 1969), The Moon in the post-Apollo era (1974), (with Jack Carter) Mapping the Moon(1974), and two atlases of the Moon, published in 1965 and 1971. This was, in addition, to many other articles on lunar astronomy, some published in specialist journals, but also in more mainstream scientific journals, such as Nature, New Scientist and Discovery. Kopal's reputation as a Moon expert, was recognised when he was interviewed on prime time US television by Walter Cronkite during the Apollo 11 landing. Kopal himself later described the 20th July 1969 as “the greatest day I have ever experienced in my life”.

Apart from his books about the Moon, Kopal also wrote a couple of more general guides to modern astronomy: Widening Horizons 1970 and Man and his Universe. 1972. Kopal also had a deep interest in the history of astronomy.

Within the international astronomical community, Kopal was an almost ubiquitous figure in the 1960s and 1970s. He was an assiduous networker, with particularly close links to astronomers in Greece, Egypt, Iraq and Japan. Many of his research students at Manchester came from overseas. and many went on to professorial chairs in their home countries. Kopal was very active in the International Astronomical Union, where he chaired the section 42 (on close binaries) for many years. He was an active member of COSPAR and between 1961-64 chaired the Lunar and Planetary Exploration Sub-Committee of the British National Committee for Space Research. On the other hand,, Kopal was not closely associated with British scientific establishment; he never became a fellow of the Royal Society, and does not appear to have been particularly close either to the Royal Greenwich Observatory or the Royal Astronomical Society.

Kopal was very active in the area of scientific publishing Apart from publishing several hundred articles himself, he established several new journals for astronomers and astrophysicists. He considered these provided a salutary challenge to the existing monopoly of astronomy journals. He established Icarus in 1962, dedicated to the field of planetary science, followed by Astronomy and Space Science in 1968, and Moon and Planets, later Earth, Moon and Planets.

In his later career, he returned to his work on binary stars, publishing Dynamics of Close Binary Systems in 1978. He retired from the University in 1981. Kopal published his memoirs Of Stars and Men: Reminiscences of an Astronomer in 1986, which was particularly informative about some of his international connections.

Kopal's sub-department of astronomy remained reasonably modest in size. A second chair in astronomy was created for the astrophysicist Franz Kahn (1926-1998) in 1966. Other significant members of staff included John Meaburn, J E Dyson, and John Hazlehurst. Kopal's secretary and later Personal assistant, Ellen B. Finlay (Ellen Carling from 1973) played an important role in maintaining Kopal's archive and was described by ZK in his autobiography as the 'third most senior member of the department' (after himself and Kahn).

Kopal retired from his chair in 1981, whereupon he became Professor Emeritus. He continued to live at Wilmslow, Cheshire until he died aged 79 on 23 June 1993. Zdenĕk Kopal married Alena Mulder in 1938. They had three daughters, Georgina, Eva, and Zdenka.

The asteroid 2628 Kopal, discovered in 1979 by the Siding Spring Observatory in Australia, was named in Kopal's honour.


The archive's various series reflect Kopal's own divisions of his papers into files;

The archive is divided into eight series, as follows:

  • KOP/1: Correspondence files
  • KOP/2: Research notebooks
  • KOP/3: Drafts and unpublished typescripts
  • KOP/4: Offprints
  • KOP/5: United States Air Force (USAF) contracts regarding the Manchester Lunar Programme
  • KOP/6: Cuttings and clippings
  • KOP/7: Personal photographs
  • KOP/8: Miscellaneous

Conditions Governing Access

The collection is open to any accredited reader, subject to the requirements of Data Protection Act 2018.

The collection includes material which is subject to the Data Protection Act 2018. Under Data Protection Act 2018, The University of Manchester Library (UML) holds the right to process personal data for research purposes. The Data Protection (Processing of Sensitive Personal Data) Order 2000 enables the UML to process sensitive personal data for research purposes. In accordance with the Data Protection Act 2018, the UML has made every attempt to ensure that all personal and sensitive personal data has been processed fairly, lawfully and accurately. Users of the archive are expected to comply with the Data Protection Act 2018, and will be required to sign a form acknowledging that they will abide by the requirements of the Act in any further processing of the material by themselves.

Some items in the archive are already closed to public inspection in line with the requirements of the Data Protection Act 2018.

Open parts of this collection, and the catalogue descriptions, may also contain personal data about living individuals.

Acquisition Information

The majority of the archive was donated to the Library by Professor Kopal sometime before 1988. Additional material (pre-1951 and post-1988) was donated some time after Kopal's death in 1993, by his daughter Zdenka Smith and Ellen B. Carling (née Finlay).

Archivist's Note

This catalogue was produced with generous support from the American Institute of Physics, Grants to Archive program, 2018.

Zdenĕk Kopal may be referred to as ZK and Ellen B. Finlay as EBF (including for the period after she married and adopted the surname Finlay-Carling or Carling) in this catalogue.

Conditions Governing Use

Photocopies and photographic copies of material in the archive can be supplied for private study purposes only, depending on the condition of the documents.

All of the items within the archive remain within copyright under the terms of the Copyright, Designs and Patents Act 1988; it is the responsibility of users to obtain the copyright holder's permission for reproduction of copyright material for purposes other than research or private study.

Prior written permission must be obtained from the Library for publication or reproduction of any material within the archive. Please contact the Head of Special Collections, John Rylands Library, 150 Deansgate, Manchester, M3 3EH.

Custodial History

The material in the archive was created or accumulated by Zdenĕk Kopal during the course of his life and retained by him until its transfer to the Library.


No further accruals are expected.

Related Material

The University of Manchester Vice-Chancellor's archive include a detailed file relating to Kopal's appointment to a chair in astronomy (VCA/7/453) and the sub-department of astronomy during Kopal's period of office (VCA/7/619)

The University of Manchester Library also holds the archives of physicist and radio astronomer Sir Bernard Lovell (1913-2012) and the Jodrell Bank Radio-Telescope Observatory (JBA.

The University of California, San Diego, Library has a correspondence file for Kopal in the Harold C. Urey papers, reference: MSS 0044, Box 59/9-12, and a similar file in the Hannes Alfvén papers (MSS 0225, Box 18/33).


Zdenĕk Kopal, Of Stars and Men: Reminiscences of an Astronomer (Bristol and Boston: Adam Hinger, 1986) is the most detailed source of information about Kopal's life. There is as yet no secondary biography.

Horst Drechsel and Miloslav Zejda (eds.), Zdenĕk Kopal's Binary Star Legacy (Springer 2005) is a collection of essays relating to ZK's binary star research.

There is a (legacy) Czech website about Kopal, hosted by his home town, Litomy l