Charles Thomas Kowal (November 8, 1940 – November 28, 2011) was an American astronomer known for his observations and discoveries in the Solar System. As a staff astronomer at Caltech's Mount Wilson and Palomar Mountain observatories between 1961 and 1984, he found the first of a new class of Solar System objects, the centaurs, discovered two moons of the planet Jupiter, and discovered or co-discovered a number of asteroids, comets and supernovae. He was awarded the James Craig Watson Medal for his contributions to astronomy in 1979.
In the 1960s, Kowal observed with the Palomar 48" Schmidt telescope, contributing observations to noted cosmologistFritz Zwicky's six-volume Catalogue of Galaxies and of Clusters of Galaxies.[nb 1] Kowal also began to search for Type Ia supernovae in other galaxies, in an effort led by Zwicky to calibrate the magnitudes of these exploding stars so that they could be used as standard candles, reliable measures of the distance of their host galaxies (work which in the present has led to accurate measurements of the expansion of the universe).[3] In the course of these Palomar supernovae surveys with the 48" Schmidt,[4] Kowal personally discovered 81 supernovae, including SN 1972e.
Kowal provided observations of new Solar System discoveries and reports of new supernovae via the IAU circular system throughout the 1970s,[6] and searched for new objects. He discovered two moons of Jupiter: Leda in 1974 and Themisto in 1975, the 13th and 14th moons of Jupiter to be found.[7] Themisto was later lost (i.e. its orbit was not known well enough to reobserve it) and was not rediscovered until 2000.
Between December 1976 and February 1985, Kowal searched 6400 square degrees of sky in the ecliptic plane for distant, slow-moving Solar System objects.[8] Only one object was found beyond Jupiter: 2060 Chiron, discovered in 1977, which had the unusual characteristic of features both like an asteroid and a comet. It became recognised as the first object in the centaur class after a second one was discovered 15 years later. Centaurs are objects with unstable orbits which orbit between Jupiter and Neptune. They are probably drawn in from the Kuiper belt by alignments with larger planets. Chiron remains one of the largest such worlds known, and one of a handful that have a comet-like coma. Kowal also discovered or co-discovered the periodic comets 99P/Kowal, 104P/Kowal, 134P/Kowal-Vavrova, 143P/Kowal-Mrkos, and 158P/Kowal-LINEAR.
In 1980, Kowal's research in astronomical history found a 1613 drawing by Galileo Galilei showing Neptune near Jupiter, predating the discovery of Neptune in 1846;[9] Kowal was awarded the inaugural R. R. Newton Award for Scientific History for this "shockingly outré" finding.[10]
Kowal moved to the new Space Telescope Science Institute in 1985, where he monitored the instruments of the Hubble Space Telescope as one of the operations astronomers. His book Asteroids: Their Nature and Utilization was published in 1988, and a second edition in 1996.
^The 48" Schmidt was then fully automated, and used for a successor survey, the Near Earth Asteroid Tracking (NEAT) survey, which ran on the Schmidt from April 2001 to April 2007.
References
^"Minor Planet Discoverers (by number)". Minor Planet Center. October 29, 2018. Retrieved February 19, 2019.
^"Query Results from the ADS Database". Retrieved December 6, 2011.
^Kowal, C. T. (December 1968). "Absolute magnitudes of supernovae". Astronomical Journal. 73: 1021–1024. Bibcode:1968AJ.....73.1021K. doi:10.1086/110763.
^Kowal, C. T.; Sargent, W. L. W.; Zwicky, F. (June 1970). "The 1969 Palomar Supernova Search". Publications of the Astronomical Society of the Pacific. 82 (487): 736. Bibcode:1970PASP...82..736K. doi:10.1086/128951.
^Helin, E. F.; Shoemaker, E. M. (1979). "The Palomar planet-crossing asteroid survey, 1973–1978". Icarus. 40 (3): 321–328. Bibcode:1979Icar...40..321H. doi:10.1016/0019-1035(79)90021-6.
^"Author Query: Kowal, C. T. Query Results from the Astronomy Database". ADS. Retrieved December 6, 2011.
^Marsden, Brian G. (October 7, 1975). "IAUC 2846: N Mon 1975 (= A0620-00); N Cyg 1975; 1975h; 1975g; 1975i; Sats OF JUPITER". Central Bureau for Astronomical Telegrams, International Astronomical Union. Retrieved December 6, 2011.
^Kowal, C. T. (January 1989). "A solar system survey". Icarus. 77 (1): 118–123. Bibcode:1989Icar...77..118K. doi:10.1016/0019-1035(89)90011-0.
^Kowal, Charles T. (December 2008). "Galileo's Observations of Neptune" (PDF). The International Journal of Scientific History. 15 (2008 December): 3. Bibcode:2008DIO....15....3K. Retrieved March 29, 2016.
^"DIO $1000 Prizes". DIO Publishing. Retrieved December 5, 2011.
^News staff reports (December 3, 2011). "Charles T. Kowal, discovered 2 of Jupiter's moons". The Buffalo News. Archived from the original on July 23, 2012. Retrieved December 5, 2011.
charles, kowal, charles, thomas, kowal, november, 1940, november, 2011, american, astronomer, known, observations, discoveries, solar, system, staff, astronomer, caltech, mount, wilson, palomar, mountain, observatories, between, 1961, 1984, found, first, class. Charles Thomas Kowal November 8 1940 November 28 2011 was an American astronomer known for his observations and discoveries in the Solar System As a staff astronomer at Caltech s Mount Wilson and Palomar Mountain observatories between 1961 and 1984 he found the first of a new class of Solar System objects the centaurs discovered two moons of the planet Jupiter and discovered or co discovered a number of asteroids comets and supernovae He was awarded the James Craig Watson Medal for his contributions to astronomy in 1979 Charles Thomas KowalBorn 1940 11 08 November 8 1940Buffalo New York USADiedNovember 28 2011 2011 11 28 aged 71 Cinebar Washington USACitizenshipUnited StatesAlma materUniversity of Southern CaliforniaKnown forDiscovery of outer Solar System objectsScientific careerFieldsAstronomyInstitutionsCaltech s Hale Observatory STScI APLMinor planets discovered 22 1 see List of discovered minor planets Contents 1 Research 2 Honours and awards 3 List of discovered minor planets 4 See also 5 Notes 6 ReferencesResearch EditIn the 1960s Kowal observed with the Palomar 48 Schmidt telescope contributing observations to noted cosmologist Fritz Zwicky s six volume Catalogue of Galaxies and of Clusters of Galaxies nb 1 Kowal also began to search for Type Ia supernovae in other galaxies in an effort led by Zwicky to calibrate the magnitudes of these exploding stars so that they could be used as standard candles reliable measures of the distance of their host galaxies work which in the present has led to accurate measurements of the expansion of the universe 3 In the course of these Palomar supernovae surveys with the 48 Schmidt 4 Kowal personally discovered 81 supernovae including SN 1972e In 1973 Caltech astronomers Eleanor Helin and Gene Shoemaker began an observing program to search out and track previously unknown near Earth asteroid the Planet Crossing Asteroid Survey PCAS a photographic plate survey that began on the Palomar 18 Schmidt telescope Although primarily employed by the supernova survey to observe on the 48 Schmidt Kowal provided crucial observations 5 of particularly faint asteroids for the PCAS program with the larger telescope His asteroid discoveries and co discoveries include the notable asteroids Aten asteroid 2340 Hathor the Apollo asteroids 1981 Midas 2063 Bacchus 2102 Tantalus and 5660 1974 MA the Amor asteroids 4596 1981 QB and 4688 1980 WF and the Trojan asteroids 2241 Alcathous and 2594 Acamas PCAS later moved to the 48 Schmidt and ran in total for nearly 25 years until June 1995 nb 2 Kowal provided observations of new Solar System discoveries and reports of new supernovae via the IAU circular system throughout the 1970s 6 and searched for new objects He discovered two moons of Jupiter Leda in 1974 and Themisto in 1975 the 13th and 14th moons of Jupiter to be found 7 Themisto was later lost i e its orbit was not known well enough to reobserve it and was not rediscovered until 2000 Between December 1976 and February 1985 Kowal searched 6400 square degrees of sky in the ecliptic plane for distant slow moving Solar System objects 8 Only one object was found beyond Jupiter 2060 Chiron discovered in 1977 which had the unusual characteristic of features both like an asteroid and a comet It became recognised as the first object in the centaur class after a second one was discovered 15 years later Centaurs are objects with unstable orbits which orbit between Jupiter and Neptune They are probably drawn in from the Kuiper belt by alignments with larger planets Chiron remains one of the largest such worlds known and one of a handful that have a comet like coma Kowal also discovered or co discovered the periodic comets 99P Kowal 104P Kowal 134P Kowal Vavrova 143P Kowal Mrkos and 158P Kowal LINEAR In 1980 Kowal s research in astronomical history found a 1613 drawing by Galileo Galilei showing Neptune near Jupiter predating the discovery of Neptune in 1846 9 Kowal was awarded the inaugural R R Newton Award for Scientific History for this shockingly outre finding 10 Kowal moved to the new Space Telescope Science Institute in 1985 where he monitored the instruments of the Hubble Space Telescope as one of the operations astronomers His book Asteroids Their Nature and Utilization was published in 1988 and a second edition in 1996 From 1996 until his retirement in 2006 he worked at the Johns Hopkins University Applied Physics Laboratory providing software for the NEAR Shoemaker spacecraft s mission to land on the asteroid Eros and mission operations support for the NASA TIMED mission Kowal died on November 28 2011 at the age of 71 11 Honours and awards EditKowal was awarded the National Academy of Sciences James Craig Watson Medal for his noteworthy astronomical discoveries particularly of Chiron Leda and numerous supernovae in 1979 12 The crater Kowal on Pluto was named in his honor citation needed List of discovered minor planets EditSee also Category Discoveries by Charles T Kowal List of minor planets discovered by Charles KowalName Discovery Date Listing1876 Napolitania 31 January 1970 list1939 Loretta 17 October 1974 list1981 Midas 6 March 1973 list2060 Chiron 18 October 1977 list2063 Bacchus 24 April 1977 list2102 Tantalus 27 December 1975 list2134 Dennispalm 24 December 1976 list2241 Alcathous 22 November 1979 list2340 Hathor 22 October 1976 list2594 Acamas 4 October 1978 list2629 Rudra 13 September 1980 list3163 Randi 28 August 1981 listName Discovery Date Listing3924 Birch 11 February 1977 list A 4312 Knacke 29 November 1978 list B 4596 1981 QB 28 August 1981 list 4688 1980 WF 29 November 1980 list 5660 1974 MA 26 June 1974 list 24617 1978 WU 29 November 1978 list B 73669 1981 WL2 25 November 1981 list 99953 1978 ND 7 July 1978 list 178284 1978 WB1 29 November 1978 list B 306375 1980 RG1 13 September 1980 listCo discovery made with A E BowellB S J BusSee also EditList of minor planet discoverers C T KowalNotes Edit Kowal was a coauthor on volumes 1 5 and 6 2 The 48 Schmidt was then fully automated and used for a successor survey the Near Earth Asteroid Tracking NEAT survey which ran on the Schmidt from April 2001 to April 2007 References Edit Minor Planet Discoverers by number Minor Planet Center October 29 2018 Retrieved February 19 2019 Query Results from the ADS Database Retrieved December 6 2011 Kowal C T December 1968 Absolute magnitudes of supernovae Astronomical Journal 73 1021 1024 Bibcode 1968AJ 73 1021K doi 10 1086 110763 Kowal C T Sargent W L W Zwicky F June 1970 The 1969 Palomar Supernova Search Publications of the Astronomical Society of the Pacific 82 487 736 Bibcode 1970PASP 82 736K doi 10 1086 128951 Helin E F Shoemaker E M 1979 The Palomar planet crossing asteroid survey 1973 1978 Icarus 40 3 321 328 Bibcode 1979Icar 40 321H doi 10 1016 0019 1035 79 90021 6 Author Query Kowal C T Query Results from the Astronomy Database ADS Retrieved December 6 2011 Marsden Brian G October 7 1975 IAUC 2846 N Mon 1975 A0620 00 N Cyg 1975 1975h 1975g 1975i Sats OF JUPITER Central Bureau for Astronomical Telegrams International Astronomical Union Retrieved December 6 2011 Kowal C T January 1989 A solar system survey Icarus 77 1 118 123 Bibcode 1989Icar 77 118K doi 10 1016 0019 1035 89 90011 0 Kowal Charles T December 2008 Galileo s Observations of Neptune PDF The International Journal of Scientific History 15 2008 December 3 Bibcode 2008DIO 15 3K Retrieved March 29 2016 DIO 1000 Prizes DIO Publishing Retrieved December 5 2011 News staff reports December 3 2011 Charles T Kowal discovered 2 of Jupiter s moons The Buffalo News Archived from the original on July 23 2012 Retrieved December 5 2011 Awards James Craig Watson Medal National Academy of Sciences 2011 Archived from the original on November 16 2011 Retrieved December 6 2011 Retrieved from https en wikipedia org w index php title Charles T Kowal amp oldid 1116028134, wikipedia, wiki, book, books, library,
