Ян Хендрик Оорт: Пионер астрономии XX века

Введение

Голландский астроном (1900–1992)

Ян Хендрик Оорт (/ɔr/t/ или /ʊər/t/; 28 апреля 1900 – 5 ноября 1992) был голландским астрономом, внесшим значительный вклад в понимание Млечного Пути и ставшим пионером в области радиоастрономии. Газета "Нью-Йорк таймс" назвала его "одним из главных исследователей Вселенной в XX веке", а на сайте Европейского космического агентства он назван "одним из величайших астрономов XX века" и отмечается, что "своими революционными открытиями он совершил переворот в астрономии". В 1955 году имя Оорта вошло в список 100 самых известных живущих людей журнала Life. Его описывали как "выведшего Нидерланды на передовые позиции послевоенной астрономии". Он открыл галактический ореол – группу звезд, вращающихся вокруг Млечного Пути, но за пределами его основного диска. Кроме того, Оорт ответственен за ряд важных выводов о кометах, включая осознание того, что их орбиты "показывали, что Солнечная система намного больше области, занимаемой планетами". Его родителями были врач, скончавшийся 12 мая 1941 года, и Рут Ханна Фабер, дочь Яна Фабера и Генриетты Софии Сюзанны Шааи, умершая 20 ноября 1957 года. Оба родителя происходили из семей священнослужителей, а его дед по отцовской линии был протестантским священником с либеральными взглядами, который "был одним из основателей более либеральной церкви в Голландии" и "одним из трех человек, осуществивших новый перевод Библии на голландский язык". Ему "наконец удалось вычислить, основываясь на различных движениях звезд, что Солнце находится примерно в 30 000 световых лет от центра Галактики и совершает полный оборот примерно за 225 миллионов лет. Он также показал, что звезды во внешних областях галактического диска вращаются медленнее, чем те, что ближе к центру. Таким образом, Галактика не вращается как единое целое, а демонстрирует так называемое 'дифференциальное вращение'". Эти ранние открытия Оорта о Млечном Пути опровергли систему Каптейна, названную в честь его научного руководителя, которая представляла галактику симметричной относительно Солнца. Как позже отметил Оорт, "Каптейн и его коллеги не осознавали, что поглощение света в галактической плоскости было настолько сильным, как оказалось".

Jan Hendrik Oort ('/ɔr//t/ or '/ʊər//t/; 28 April 1900 – 5 November 1992) was a Dutch astronomer who made significant contributions to the understanding of the Milky Way and who was a pioneer in the field of radio astronomy. The New York Times called him "one of the century's foremost explorers of the universe"; the European Space Agency website describes him as "one of the greatest astronomers of the 20th century" and states that he "revolutionised astronomy through his ground breaking discoveries." In 1955, Oort's name appeared in Life magazine's list of the 100 most famous living people. He has been described as "putting the Netherlands in the forefront of postwar astronomy." He discovered the galactic halo, a group of stars orbiting the Milky Way but outside the main disk. Additionally Oort is responsible for a number of important insights about comets, including the realization that their orbits "implied there was a lot more solar system than the region occupied by the planets." a physician, who died on May 12, 1941, and Ruth Hannah Faber, who was the daughter of Jan Faber and Henrietta Sophia Susanna Schaaii, and who died on November 20, 1957. Both of his parents came from families of clergymen, with his paternal grandfather, a Protestant clergyman with liberal ideas, who "was one of the founders of the more liberal Church in Holland" and who "was one of the three people who made a new translation of the Bible into Dutch." He "was finally able to calculate, on the basis of the various stellar motions, that the Sun was some 30,000 light years from the center of the Galaxy and took about 225 million years to complete its orbit. He also showed that stars lying in the outer regions of the galactic disk rotated more slowly than those nearer the center. The Galaxy does not therefore rotate as a uniform whole but exhibits what is known as 'differential rotation'." These early discoveries by Oort about the Milky Way overthrew the Kapteyn system, named after his mentor, which had envisioned a galaxy that was symmetrical around the Sun. As Oort later noted, "Kapteyn and his co workers had not realized that the absorption in the galactic plane was as bad as it turned out to be."

Исследования комет

Оорт продолжил изучать кометы, сформулировав ряд революционных гипотез. Он предположил, что Солнечная система окружена массивным облаком, состоящим из миллиардов комет, многие из которых — долгопериодические кометы, происходящие из облака далеко за орбитами Нептуна и Плутона. Это облако теперь известно как облако Оорта. Он также понял, что эти внешние кометы, приходящие из-за пределов Плутона, могут "попасть в гравитационную ловушку Юпитера и стать периодическими кометами, такими как комета Галлея". Согласно одному источнику, "Оорт был одним из немногих людей, видевших комету Галлея в двух отдельных появлениях. В возрасте 10 лет он был с отцом на берегу в Нордвийке, Нидерланды, когда впервые увидел комету. В 1986 году, через 76 лет, он поднялся на самолете и смог увидеть знаменитую комету еще раз". "Коллеги помнили его как высокого, худощавого и учтивого человека с доброжелательным характером", — сообщалось в некрологе New York Times. Oort, J. H. & M. Schmidt, "Differences between New and Old Comets," Bull. Astron. Inst. Neth. 11, 259–70 (1951). Westerhout, G. & J. H. Oort, "A Comparison of the Intensity Distribution of Radio frequency Radiation with a Model of the Galactic System," Bull. Astron. Inst. Neth. 11, 323–33 (1951). Morgan, H. R. & J. H. Oort, "A New Determination of the Precession and the Constants of Galactic Rotation," Bull. Astron. Inst. Neth. 11, 379–84 (1951). Oort, J. H. "Problems of Galactic Structure," Ap. J. 116, 233–250 (1952) [Henry Norris Russell Lecture, 1951]. Oort, J. H., "Outline of a Theory on the Origin and Acceleration of Interstellar Clouds and O Associations," Bull. Astr. Inst. Neth. 12, 177–86 (1954). van de Hulst, H. C., C. A. Muller, & J. H. Oort, "The spiral structure of the outer part of the Galactic System derived from the hydrogen mission at 21 cm wavelength," Bull. Astr. Inst. Neth. 12, 117–49 (1954). van Houten, C. J., J. H. Oort, & W. A. Hiltner, "Photoelectric Measurements of Extragalactic Nebulae," Ap. J. 120, 439–53 (1954). Oort, Jan H. & Lyman Spitzer, Jr., "Acceleration of Interstellar Clouds by O Type Stars," Ap. J. 121, 6–23 (1955). Oort, J. H., "Measures of the 21 cm Line Emitted by Interstellar Hydrogen," Vistas in Astronomy. 1, 607–16 (1955). Oort, J. H., "A New Southern Hemisphere Observatory," Sky & Telescope 15, 163 (1956). Oort, J. H. & Th. Walraven, "Polarization and Composition of the Crab Nebula," Bull. Astr. Inst. Neth. 12, 285–308 (1956). Oort, J. H., "Die Spiralstruktur des Milchstraßensystems," Mitt. Astr. Ges. 7, 83–87 (1956). Oort, J. H., F. J. Kerr, & G. Westerhout, "The Galactic System as a Spiral Nebula," MNRAS 118, 379–89 (1958). Oort, J. H., "Summary – From the Astronomical Point of View," in Ricerche Astronomiche, Vol. 5, Specola Vaticana, Proceedings of a Conference at Vatican Observatory, Castel Gandolfo, May 20–28, 1957, ed. by D. J. K. O'Connell (North Holland, Amsterdam & Interscience, NY, 1958), 507–29. Oort, Jan H., "Radio frequency Studies of Galactic Structure," Handbuch der Physik vol. 53, 100–28 (1959). Oort, J. H., "A Summary and Assessment of Current 21 cm Results Concerning Spiral and Disk Structures in Our Galaxy," in Paris Symposium on Radio Astronomy, IAU Symposium no. 9 and URSI Symposium no. 1, held 30 July – 6 August 1958, ed. by R. N. Bracewell (Stanford University Press, Stanford, CA, 1959), 409–15. Rougoor, G. W. & J. H. Oort, "Neutral Hydrogen in the Central Part of the Galactic System," in Paris Symposium on Radio Astronomy, IAU Symposium no. 9 and URSI Symposium no. 1, held 30 July – 6 August 1958, ed. by R. N. Bracewell (Stanford University Press, Stanford, CA, 1959), pp. 416–22. Oort, J. H. & G. van Herk, "Structure and dynamics of Messier 3," Bull. Astr. Inst. Neth. 14, 299–321 (1960). Oort, J. H., "Note on the Determination of Kz and on the Mass Density Near the Sun," Bull. Astr. Inst. Neth. 15, 45–53 (1960). Rougoor, G. W. & J. H. Oort, "Distribution and Motion of Interstellar Hydrogen in the Galactic System with Particular Reference to the Region within 3 Kiloparsecs of the Center," Proc. Natl. Acad. Sci. 46, 1–13 (1960). Oort, J. H. & G. W. Rougoor, "The Position of the Galactic Centre," MNRAS 121, 171–73 (1960). Oort, J. H., "The Galaxy," IAU Symposium 20, 1–9 (1964). Oort, J. H. "Stellar Dynamics," in A. Blaauw & M. Schmidt, eds., Galactic Structure (Univ. of Chicago Press, Chicago, 1965), pp. 455–512. Oort, J. H., "Possible Interpretations of the High Velocity Clouds," Bull. Astr. Inst. Neth. 18, 421–38 (1966). Oort, J. H., "Infall of Gas from Intergalactic Space," Nature 224, 1158–63 (1969). Oort, J. H., "The Formation of Galaxies and the Origin of the High Velocity Hydrogen.," Astronomy & Astrophysics 7, 381–404 (1970). Oort, J. H., "The Density of the Universe," Astronomy & Astrophysics 7, 405 (1970). Oort, J. H., "Galaxies and the Universe," Science 170, 1363–70 (1970). van der Kruit, P. C., J. H. Oort, & D. S. Mathewson, "The Radio Emission of NGC 4258 and the Possible Origin of Spiral Structure," Astronomy & Astrophysics 21, 169–84 (1972). Oort, J. H., "The Development of our Insight into the Structure of the Galaxy between 1920 and 1940," Ann. NY Acad. Sci. 198, 255–66 (1972). Oort, Jan H. "On the Problem of the Origin of Spiral Structure," Mitteilungen der AG 32, 15–31 (1973) [Karl Schwarzschild Lecture, 1972]. Oort, J. H. & L. Plaut, "The Distance to the Galactic Centre Derived from RR Lyrae Variables, the Distribution of these Variables in the Galaxy's Inner Region and Halo, and A Rediscussion of the Galactic Rotation Constants," Astronomy & Astrophysics 41, 71–86 (1975). Strom, R. G., G. K. Miley, & J. Oort, "Giant Radio Galaxies," Sci. Amer. 233, 26 (1975). Pels, G., J. H. Oort, & H. A. Pels Kluyver, "New Members of the Hyades Cluster and a Discussion of its Structure," Astronomy & Astrophysics 43, 423–41 (1975). Rubin, Vera C., W. Kent Ford, Jr., Charles J. Peterson, & J. H. Oort,"New Observations of the NGC 1275 Phenomenon," Ap. J. 211, 693–96 (1977). Oort, J. H., "The Galactic Center," Annual Review of Astronomy & Astrophysics 15, 295–362 (1977). Oort, J. H., "Superclusters and Lyman α Absorption Lines in Quasars," Astronomy & Astrophysics 94, 359–64 (1981). Oort, J. H., H. Arp, & H. de Ruiter, "Evidence for the Location of Quasars in Superclusters," Astronomy & Astrophysics 95, 7–13 (1981). Oort, J. H., "Superclusters," Annual Review of Astronomy & Astrophysics 21, 373–428 (1983). Oort, J. H., "Structure of the Universe," in Early Evolution of the Universe and its Present Structure; Proceedings of the Symposium, Kolymbari, Greece, August 30 – September 2, 1982, (Reidel, Dordrecht & Boston, 1983), 1–6. Oort, Jan H. "The Origin and Dissolution of Comets (1986 Halley Lecture)" Observatory 106, 186–93 (1986). Oort, Jan H. "Origin of Structure in the Universe," Publ. Astron. Soc. Jpn. 40, 1–14 (1988). Oort, J. H., "Questions Concerning the Large scale Structure of the Universe," in Problems in Theoretical Physics and Astrophysics: Collection of Articles in Celebration of the 70th Birthday of V. L. Ginzburg (Izdatel'stvo Nauka, Moscow, 1989), pp. 325–37. Oort, J. H., "Orbital Distribution of Comets," in W. F. Huebner, ed., Physics and Chemistry of Comets (Springer Verlag, 1990), pp. 235–44 (1990). Oort, J. H., "Exploring the Nuclei of Galaxies," Mercury 21, 57 (1992). Oort, J. H., "Non Light Emitting Matter in the Stellar System," public lecture of 1926, reprinted in The Legacy of J. C. Kapteyn, ed. by P. C. van der Kruit and K. van Berkel (Kluwer, Dordrecht, 2000) [abstract].

Oort went on to study comets, which he formulated a number of revolutionary hypotheses. He hypothesized that the Solar System is surrounded by a massive cloud consisting of billions of comets, many of them "long period" comets that originate in a cloud far beyond the orbits of Neptune and Pluto. This cloud is now known as the Oort Cloud. He also realized that these external comets, from beyond Pluto, can "become trapped into tighter orbits by Jupiter, and become periodic comets, like Halley's comet." According to one source, "Oort was one of the few people to have seen Comet Halley on two separate apparitions. At the age of 10, he was with his father on the shore at Noordwijk, Netherlands, when he first saw the comet. In 1986, 76 years later, he went up in a plane and was able to see the famous comet once more." "Colleagues remembered him as a tall, lean and courtly man with a genial manner," reported his New York Times obituary. Oort, J. H. & M. Schmidt, "Differences between New and Old Comets," Bull. Astron. Inst. Neth. 11, 259–70 (1951). Westerhout, G. & J. H. Oort, "A Comparison of the Intensity Distribution of Radio frequency Radiation with a Model of the Galactic System," Bull. Astron. Inst. Neth. 11, 323–33 (1951). Morgan, H. R. & J. H. Oort, "A New Determination of the Precession and the Constants of Galactic Rotation," Bull. Astron. Inst. Neth. 11, 379–84 (1951). Oort, J. H. "Problems of Galactic Structure," Ap. J. 116, 233–250 (1952) [Henry Norris Russell Lecture, 1951]. Oort, J. H., "Outline of a Theory on the Origin and Acceleration of Interstellar Clouds and O Associations," Bull. Astr. Inst. Neth. 12, 177–86 (1954). van de Hulst, H. C., C. A. Muller, & J. H. Oort, "The spiral structure of the outer part of the Galactic System derived from the hydrogen mission at 21 cm wavelength," Bull. Astr. Inst. Neth. 12, 117–49 (1954). van Houten, C. J., J. H. Oort, & W. A. Hiltner, "Photoelectric Measurements of Extragalactic Nebulae," Ap. J. 120, 439–53 (1954). Oort, Jan H. & Lyman Spitzer, Jr., "Acceleration of Interstellar Clouds by O Type Stars," Ap. J. 121, 6–23 (1955). Oort, J. H., "Measures of the 21 cm Line Emitted by Interstellar Hydrogen," Vistas in Astronomy. 1, 607–16 (1955). Oort, J. H., "A New Southern Hemisphere Observatory," Sky & Telescope 15, 163 (1956). Oort, J. H. & Th. Walraven, "Polarization and Composition of the Crab Nebula," Bull. Astr. Inst. Neth. 12, 285–308 (1956). Oort, J. H., "Die Spiralstruktur des Milchstraßensystems," Mitt. Astr. Ges. 7, 83–87 (1956). Oort, J. H., F. J. Kerr, & G. Westerhout, "The Galactic System as a Spiral Nebula," MNRAS 118, 379–89 (1958). Oort, J. H., "Summary – From the Astronomical Point of View," in Ricerche Astronomiche, Vol. 5, Specola Vaticana, Proceedings of a Conference at Vatican Observatory, Castel Gandolfo, May 20–28, 1957, ed. by D. J. K. O'Connell (North Holland, Amsterdam & Interscience, NY, 1958), 507–29. Oort, Jan H., "Radio frequency Studies of Galactic Structure," Handbuch der Physik vol. 53, 100–28 (1959). Oort, J. H., "A Summary and Assessment of Current 21 cm Results Concerning Spiral and Disk Structures in Our Galaxy," in Paris Symposium on Radio Astronomy, IAU Symposium no. 9 and URSI Symposium no. 1, held 30 July – 6 August 1958, ed. by R. N. Bracewell (Stanford University Press, Stanford, CA, 1959), 409–15. Rougoor, G. W. & J. H. Oort, "Neutral Hydrogen in the Central Part of the Galactic System," in Paris Symposium on Radio Astronomy, IAU Symposium no. 9 and URSI Symposium no. 1, held 30 July – 6 August 1958, ed. by R. N. Bracewell (Stanford University Press, Stanford, CA, 1959), pp. 416–22. Oort, J. H. & G. van Herk, "Structure and dynamics of Messier 3," Bull. Astr. Inst. Neth. 14, 299–321 (1960). Oort, J. H., "Note on the Determination of Kz and on the Mass Density Near the Sun," Bull. Astr. Inst. Neth. 15, 45–53 (1960). Rougoor, G. W. & J. H. Oort, "Distribution and Motion of Interstellar Hydrogen in the Galactic System with Particular Reference to the Region within 3 Kiloparsecs of the Center," Proc. Natl. Acad. Sci. 46, 1–13 (1960). Oort, J. H. & G. W. Rougoor, "The Position of the Galactic Centre," MNRAS 121, 171–73 (1960). Oort, J. H., "The Galaxy," IAU Symposium 20, 1–9 (1964). Oort, J. H. "Stellar Dynamics," in A. Blaauw & M. Schmidt, eds., Galactic Structure (Univ. of Chicago Press, Chicago, 1965), pp. 455–512. Oort, J. H., "Possible Interpretations of the High Velocity Clouds," Bull. Astr. Inst. Neth. 18, 421–38 (1966). Oort, J. H., "Infall of Gas from Intergalactic Space," Nature 224, 1158–63 (1969). Oort, J. H., "The Formation of Galaxies and the Origin of the High Velocity Hydrogen.," Astronomy & Astrophysics 7, 381–404 (1970). Oort, J. H., "The Density of the Universe," Astronomy & Astrophysics 7, 405 (1970). Oort, J. H., "Galaxies and the Universe," Science 170, 1363–70 (1970). van der Kruit, P. C., J. H. Oort, & D. S. Mathewson, "The Radio Emission of NGC 4258 and the Possible Origin of Spiral Structure," Astronomy & Astrophysics 21, 169–84 (1972). Oort, J. H., "The Development of our Insight into the Structure of the Galaxy between 1920 and 1940," Ann. NY Acad. Sci. 198, 255–66 (1972). Oort, Jan H. "On the Problem of the Origin of Spiral Structure," Mitteilungen der AG 32, 15–31 (1973) [Karl Schwarzschild Lecture, 1972]. Oort, J. H. & L. Plaut, "The Distance to the Galactic Centre Derived from RR Lyrae Variables, the Distribution of these Variables in the Galaxy's Inner Region and Halo, and A Rediscussion of the Galactic Rotation Constants," Astronomy & Astrophysics 41, 71–86 (1975). Strom, R. G., G. K. Miley, & J. Oort, "Giant Radio Galaxies," Sci. Amer. 233, 26 (1975). Pels, G., J. H. Oort, & H. A. Pels Kluyver, "New Members of the Hyades Cluster and a Discussion of its Structure," Astronomy & Astrophysics 43, 423–41 (1975). Rubin, Vera C., W. Kent Ford, Jr., Charles J. Peterson, & J. H. Oort,"New Observations of the NGC 1275 Phenomenon," Ap. J. 211, 693–96 (1977). Oort, J. H., "The Galactic Center," Annual Review of Astronomy & Astrophysics 15, 295–362 (1977). Oort, J. H., "Superclusters and Lyman α Absorption Lines in Quasars," Astronomy & Astrophysics 94, 359–64 (1981). Oort, J. H., H. Arp, & H. de Ruiter, "Evidence for the Location of Quasars in Superclusters," Astronomy & Astrophysics 95, 7–13 (1981). Oort, J. H., "Superclusters," Annual Review of Astronomy & Astrophysics 21, 373–428 (1983). Oort, J. H., "Structure of the Universe," in Early Evolution of the Universe and its Present Structure; Proceedings of the Symposium, Kolymbari, Greece, August 30 – September 2, 1982, (Reidel, Dordrecht & Boston, 1983), 1–6. Oort, Jan H. "The Origin and Dissolution of Comets (1986 Halley Lecture)" Observatory 106, 186–93 (1986). Oort, Jan H. "Origin of Structure in the Universe," Publ. Astron. Soc. Jpn. 40, 1–14 (1988). Oort, J. H., "Questions Concerning the Large scale Structure of the Universe," in Problems in Theoretical Physics and Astrophysics: Collection of Articles in Celebration of the 70th Birthday of V. L. Ginzburg (Izdatel'stvo Nauka, Moscow, 1989), pp. 325–37. Oort, J. H., "Orbital Distribution of Comets," in W. F. Huebner, ed., Physics and Chemistry of Comets (Springer Verlag, 1990), pp. 235–44 (1990). Oort, J. H., "Exploring the Nuclei of Galaxies," Mercury 21, 57 (1992). Oort, J. H., "Non Light Emitting Matter in the Stellar System," public lecture of 1926, reprinted in The Legacy of J. C. Kapteyn, ed. by P. C. van der Kruit and K. van Berkel (Kluwer, Dordrecht, 2000) [abstract].

Биографические материалы

Блау, Адриан, Биографическая энциклопедия астрономов (Спрингер, Нью-Йорк, 2007), стр. 853–55. Чапман, Дэвид М. Ф., «Размышления: Ян Хендрик Оорт – Вращающиеся галактики и облака комет», JRASC 94, 53–54 (2000). ESA Space Science, «Пионер комет: Ян Хендрик Оорт», 27 февраля 2004 г. Катгерт Меркелин, Й., Университет Лейдена, «Ян Оорт, астроном». Katgert Merkelijn, J. K.: Письма и работы Яна Хендрика Оорта, хранящиеся в Университетской библиотеке Лейдена. Дордрехт, Kluwer Academic Publishers, 1997. Оорт, Й. Х., «Некоторые заметки о моей жизни как астронома», Annual Review of Astronomy & Astrophysics 19, 1 (1981). van de Hulst, H. C., Биографические мемуары Королевского общества Лондона 40, 320–26 (1994). van der Kruit, Питер С.: Ян Хендрик Оорт. Мастер Галактической системы. Springer Nature, 2019. van Woerden, Hugo, Willem N. Brouw и Henk C. van de Hulst, редакторы, «Оорт и Вселенная: очерк исследований и личности Оорта» (D. Reidel, Dordrecht, 1980).

Некрологи

Blaauw, Adriaan, Zenit jaarg, 196–210 (1993). Blaauw, Adriaan & Maarten Schmidt, PASP 105, 681 (1993). Blaauw, Adriaan, "Oort im Memoriam," в Leo Blitz & Peter Teuben, eds., 169-й симпозиум МАУ: Неразрешенные проблемы Млечного Пути, (Kluwer Acad. Publishers, 1996), стр. xv–xvi. Pecker, J. C., "Жизнь и творчество Яна Хендрика Оорта," Comptes Rendus de l'Académie des Sciences: La Vie des Science 10, 5, 535–40 (1993). van de Hulst, H. C., QJRAS 35, 237–42 (1994). van den Bergh, Sidney, "Астрономическая жизнь: J. H. Oort (1900–1992)," JRASC 87, 73–76 (1993). Woltjer, L., J. Astrophys. Astron. 14, 3–5 (1993). Woltjer, Lodewijk, Physics Today 46, 11, 104–05 (1993).