Paul Murdin

{{short description|British astronomer}}

{{Use dmy dates|date=November 2018}}

{{Use Irish English|date=November 2018}}

{{Infobox officeholder

| honorific_prefix = Prof

| name =

| honorific_suffix = {{postnominals|country=GBR|OBE|FRAS}}

| image =Paul Murdin and Roger Davies, NAM 2012.jpg

| caption =Paul Murdin and Roger Davies, NAM (2012)

| image_size =

| office = President of the European Astronomical Society

| order = 2nd

| term_start = 21 August 1993

| term_end = 5 July 1997

| predecessor = Lodewijk Woltjer

| successor = {{ill|Jean-Paul Zahn|fr|display=1}}

| birth_name =

| birth_date = {{Birth date and age|df=y|1942|1|5}}

| birth_place =

| residence =

| citizenship = British

| ethnicity =

| footnotes =

| spouse = Lesley Murdin

| children = 3

| website =

| module = {{Infobox scientist |embed=yes

| alma_mater = {{Plainlist|

• University of Oxford (MA)
• University of Rochester (PhD)}}

| awards =}}

}}

Paul Geoffrey Murdin {{postnominals|country=GBR|OBE|FRAS}} (born 5 January 1942) is a British astronomer. He identified the first clear candidate for a black hole, Cygnus X-1, with his colleague Louise Webster.

He studied Mathematics and Physics at the universities of Oxford and Rochester. In 1962, he took an eight-week summer residential course supporting researchers at the Royal Greenwich Observatory in Herstmonceux and at the end was offered a post by the Astronomer Royal, Richard Woolley. He left to study a PhD at Rochester and returned to the RGO in 1970 as a research fellow. During his three-year contract there, he wondered what he could contribute to find out about the provenance of powerful cosmic x-ray sources that had recently been detected, particularly Cygnus X-1.

After he had made unsuccessful searches for light variations and unusual spectra among the hundreds of stars within the area of positional uncertainty of the X-ray source, a radio star was found that was coincident with a star HDE226868. He decided, with the Australian Louise Webster, to investigate whether the star was a binary star, possibly with one of the pair being the X-ray source as well as a radio source, but not being visible. They measured the Doppler shift to find that HDE226868 was a binary star with an orbit of 5.6 days orbiting an invisible partner, presumably the source of the X-rays, and which they calculated to be certainly more than 2.5 and probably more than six solar masses. Such a star cannot be a white dwarf or neutron star and they assumed this body to be a black hole.

With Louise Webster, he submitted a paper with "modest" language to Nature, only mentioning the term “black hole” in the final sentence.{{cite journal|last1=Webster |first1=B.L. |last2=Murdin |first2=P. |journal=Nature|title=P. Cygnus X-1—a Spectroscopic Binary with a Heavy Companion?|volume= 235 |pages=37–38|year=1972|issue=5332 |doi=10.1038/235037a0 |bibcode=1972Natur.235...37W |s2cid=4195462 |url=https://doi.org/10.1038/235037a0}} Woolley was quite conservative in his views on astronomy, regarding black holes as "fanciful" (also famously dismissing worthwhile space exploration as "utter bilge"). Astronomer Charles Thomas Bolton then published a paper with a similar conclusion and more astronomers followed suit. The discovery helped Murdin to secure his future employment.{{cite book|last=Murdin|first=Paul|title=Full Meridian of Glory: Perilous Adventures in the Competition to Measure the Earth|publisher=Copernicus Books|location=New York|year=2009}}{{cite episode|title=Black Hole Apocalypse|network=WGBH Boston/ARTE France|series=Nova|last=DeNooyer|first=Rushmore|date=2018}}

He and Webster were amongst the first staff astronomers at the Anglo-Australian Telescope and he continued in his vein of discovery using similar techniques. He returned to the Royal Greenwich Observatory and worked on developing the UK-Netherlands observatory at La Palma, which became the Isaac Newton Group of Telescopes. He was its first head of operations until 1987. He was the director of the Royal Observatory, Edinburgh from 1991–93. Then he joined the Particle Physics and Astronomy Research Council, planning and developing the UK's space research policy. He was President of the European Astronomical Society and Treasurer of the Royal Astronomical Society (to which he'd first been elected as a Junior Member at the age of 17 in 1959, moving to Fellow in April 1963), during which time membership increased, its public outreach programme was established and its journal became the most prominent worldwide. He presided over or chaired various committees of the International Astronomical Union (IAU).{{cite web|url=https://www.wolfson.cam.ac.uk/alumni/wolfsonplus/PaulMurdin|title=Paul Murdin receives the 2012 Royal Astronomical Society Award|website=|access-date=1 November 2018}}{{cite web|url=https://www.iau.org/administration/membership/individual/2115/|title=Paul G. Murdin|website=www.iau.org|access-date=1 November 2018}}{{cite journal|journal=Quarterly Journal of the Royal Astronomical Society|title=Reports of meetings: meeting of 1963, April 10|volume=4|pages=271|year=1963|bibcode=1963QJRAS...4..271.|url=http://adsabs.harvard.edu/full/1963QJRAS...4..271.}}

He has authored and edited academic and popular books on astronomy and has written for many journals and newspapers, and well as having appeared regularly on television and radio programmes. In 2023 he was a guest on the BBC Radio 4 programme The Life Scientific.{{cite web|title= The first ever identification of a black hole|url=https://www.bbc.co.uk/programmes/m001qdln|accessdate=12 September 2023}} Now retired and living in Cambridge, he is a visiting professor at Liverpool John Moores University, Senior Fellow Emeritus at the Institute of Astronomy, Cambridge and Senior Member at Wolfson College.{{cite book|url=https://books.google.com/books?id=017WoAEACAAJ|title=Discovering the Universe: The Story of Astronomy|isbn=9780233004426|access-date=28 October 2018|last1=Murdin|first1=Paul|date=3 February 2015|publisher=Andre Deutsch }}