Walter Baade,Observational Astrophysicist,(1): The Preparation 1893–1931

[WB], “Entwicklung der Fixsterne” [a notebook], HHL; [WB], [text for invited paper at AAS meeting, symposium at Perkins Observatory, 30 Dec. 1947], 15 pp., large handwritten sheets, HHL.

Heckmann O. , Sterne, Kosmos, Weltmodelle: Erlebte Astronomie (Munich, 1976) contains many facts of Baade's life and career, and is used as a source throughout this paper. Heckmann's obituary article (ref. 3 below) is reprinted in it, but without the list of Baade's publications. Another good obituary article, emphasizing his training and early life in Germany, is Wachmann A. A. , “Walter Baade”, Die Sterne, xxxvi (1960), 204–7. Schmidt-Kaler Th. , “Walter Baades wissenschaftliche Genealogie”, Die Sterne, lxx (1994), 90–100 gives a complete account of Baade's education and of his teachers' research careers.

Heckmann O. , “Walter Baade”, MAG, cxiv (1961), 5–11; WB to [RS], 16 Aug., 21 Aug. 1919, HO.

Osterbrock D. E. Brashear R. A. and Gwinn J. A. , “Young Edwin Hubble”, Mercury, xix (1990), 2–14; Ambronn L. to [RS], [∼21 Aug. 1919], Hartmann J. to [RS], 28 Aug. [19] 19, RS to WB, 19 Sep. 1919, HO.

RS to [L. Ambronn], 19 Aug. 1919, [RS] to [Hamburg] University Authorities, [∼31] Aug. 1919, HO.

RS, “Hamburg Bergedorf” [Annual report of observatory for 1921], VJS, lvii (1922), 103–11.

WB to [ Bailey S. I. ], 4 May 1921, WB to [HS], 7 May 1921, B[ailey] S. I. to WB, 2 June 1921, Leavittto H. S. WB, 15 July 1921, HCO.

HS to WB, 5 July, 28 Aug. 1922, 5 Jan. 1923, WB to [H]S, 15 July, 11 Aug. 1922, 17 Jan. 1923, HCO.

WB, “7 Veränderliche in der Umgebung des Kugelhaufens M 53”, MHSB, v (1922), 35–39.

RS to WB, 12 Apr. 1920, HO; WB to W. W. Campbell, 7 Apr. 1923, SLO.

RS, Report on the observation of the total solar eclipse of Jan. 24, 1925 at sea, [∼15 Mar. 1925], HO.

RS to HS, 15 Feb. 1925, HS to RS, 13 Mar. 1925, HCO; HS to International Education Board, 13 Mar. 1925, RAC.

WB to International Education Board, 11 Apr. 1925.RS to A. Trowbridge, 12 Apr. 1925, RS to HS, 14 Apr. 1925, HO.

Trowbridge A. to Trowbridge A. , 16 Apr. 1925, Rose W. to Rose W. , 27 Apr. 1925, Brierly W. W. to WB, 25 June 1925, Lund W. to Lund W. , 8 Oct. 1925, RAC.

WB to [HS], 13 Apr., 1 June, 13 July 1925, HS to WB, 14 Apr., 2 May, 20 June, 3 Aug. 1925, HCO.

Tisdale W. E. to WB, 15 Sep. 1926, Tisdale W. E. to Tisdale W. E. , 29 Sep. 1926, WB to Tisdale W. E. , 24 Nov. 1926, RAC.

WB, “Photographische Beobachtungen von Kometen und Planeten”, AN, ccxxvii (1926), cols 119–24.

See ref. 6.

WB, “17 Neue Veränderliche in Kugelhaufen Messier 53 (NGC 5024)”, MHSB, vi (1926), 67.

WB, “Der kugelförmige Sternhaufen NGC 5466”, MHSB, vi (1926), 61–65.

WB, “5 isolierte Haufenveränderliche in der Umgeburg des Kugelhaufens NGC 5466”, MHSB, vi (1926), 66.

Lund W. to Commissioner of Immigration, 14 Feb. 1926, RAC.

“List of I-E-B Fellowships, Germany”, 10 May 1939, RAC.

Bok B. J. , “Harlow Shapley 1885–1972”, Biographical memoirs, National Academy of Sciences, xlix (1978), 241–91; Gingerich O. , “Through rugged ways to the galaxies”, Journal for the history of astronomy, xxi (1990), 77–88.

It is impossible to know certainly or to document Baade's impressions of American astronomy in 1926–27, for he was far too diplomatic to express them openly. He may have written about them to close personal friends in Germany (such as Hanni Bohlmann, his future wife), but if he did, no letters have survived in archives known to me. However, he was remarkably consistent in most of his views all of his life. My comments in this entire section are therefore based on my own memories of Baade's later attitudes, expressed in many conversations I had with him in the years 1953–58, of lectures I heard him give (in which he was by then much less guarded than in his letters) at the University of Michigan in 1953 (mimeographed notes exist, prepared by the auditors, which give a little of the flavour of his remarks), of a Caltech graduate course which he gave and I attended, and of several colloquia I heard him give in those years. They are also based on the mimeographed notes from a graduate course he gave at Harvard in 1958, prepared by R. B. Rodman from a tape recording, which were eventually published in facsimile as WB, Evolution in stars and galaxies (Ann Arbor, 1980). These notes served as the basis for the book, WB, Evolution of stars and galaxies (Cambridge, 1963), ed. by CPG, who had organized and attended the course. She believed that the original notes reproduced too much of Baade's “very personal and often critical tone” which was “quite appropriate in a lecture but most unfortunate on a printed page” and cut all vestiges of it out of the book. (CPG to J. H. Oort, 14 Nov. 1960, HHL).

CPG, An autobiography and other recollections, ed. by Haramundanis K. (Cambridge, 1984).

RS to EBF, 29 Oct., 30 Nov. 1925, EBF to RS, 12 Nov. 1925, WB to [EBF], 21 Dec. 1925, 21 Mar., 4 Apr. 1926, EBF to WB, 23 Mar., 13 Apr. 1926, YOA; EBF, “Yerkes Observatory” [Annual report for 1925–26], Publications of the AAS, v (1927), 445–8.

Plaskett J. S. to [W]B, 14 June 1926, HHL.

RS to RGA, 14 Oct. 1923, 15 Feb. 1924, 29 Oct. 1925, WB to RGA, 21 Dec. 1925, 2 June, 13 July 1926 (telegram), RGA to WB, 7 June 1926, SLO.

RS to WSA, 29 Oct. 1925, WSA to RS, 2 Dec. 1925, HHL; WB and Malmquist K. G. , “Die Verwendung der Seareschen Methode zur Bestimmung der Farbenindex (exposure-ratio) für Durchmusterungszwecke”, MHSB, v (1924), 135–47.

WB to [FH]S, 29 July 1930, FHS to WB, 23 Oct. 1930, HHL.

WB to [H]S, 7 Oct. 1926, HCO.

See ref. 6.

WB, “Der Sternhaufen NGC 5053”, AN, ccxxxii (1927), cols 193–9.

WB, “Über eine Möglichkeit, die Pulsatsionstheorie der δ Cephei- Veränderlichen zu prüfen”, AN, ccxxviii (1926), cols 359–62.

Wesselink A. J. , “The observations of brightness, colour and radial velocity of δ Cephei and the pulsation hypothesis”, Bulletin of the astronomical institutes of the Netherlands, x (1946), 91–99.

WB and Pauli W. Jr , “Über den auf die Teilchen in den Kometenschweifen ausgeübten Strahlungsdruck”, Naturwissenchaften, xv (1927), 49–51.

WB to [W. Lund], 20 Dec. 1926, RAC; HS to WB, 15 Feb. 1927, HCO.

WB to [H]S, 5 Mar. 1927, HCO.

RS, “Hamburg Bergedorf”, VJS, lxiii (1928), 159–72.

Higher Educational Authorities , Hamburg to [Hamburg] Observatory, 21 Sep. 1927, HHL; ditto, 10 Nov. 1927, HO.

RS, “Hamburg Bergedorf”, VJS, lxiv (1929), 193–212.

WB, “Untersuchung von zwei Milchstrassenfeldern auf Veränderliche”, AN, ccxxxii (1927), cols 65–70.

See ref. 34.

HS to WB, 16 Jan. 1928, HCO.

WB to [H]S, 20 Aug. 1928, HS to WB, 5 Sep. 1928, HCO.

See ref. 40; also Luvten W. J. , “Total solar eclipse of July 29, 1927 at Jokkmukk”, Popular astronomy, xxxvi (1928), 75–78.

Wachmann A. A. , “From the life of Bernhard Schmidt”, Sky & telescope, xv (1955), no. 1, 17–23; Marx S. and Pfau W. , Astrophotography with the Schmidt telescope (Cambridge, 1992).

WB, “Bericht über die Hamburgische Sonnenfinsternes-Expedition nach den Philippinen”, [∼15 June 1929], [15 pp. typed report], HO.

Schmidt B. , “Ein lichtstarkes, komafreies Spiegelsystem”, MHSB, vii (1931), 15. An English translation is published in Marx and Pfau , op. cit. (ref. 48), 156–7.

WB to CPG, [∼30] Apr. 1946, Owen Gingerich Collection.

[W.] Pauli to [W]B, 2 Mar. 1927, HHL.

WB to Higher Educational Authorities, Hamburg, 2 Jan. 1928, HO; WB to Herr Oberregierungsrat [Stier], [Jena], 14 Jan. 1928, HHL.

Herr Oberregierungsrat Stier to WB, 5 Apr. 1928, WB to Herr [Stier], 18 Apr. 1928, [WB], “Denkschrift über den Ausbau der Jenaer Sternwarte” [typed 7-page plan], 3 May 1928, WB to Prof. [Straubel], 4 May 1928, WB to Herr Oberregierungsrat [Stier], 4 May 1928, Herr Stier to WB, 26 June 1928, HHL.

O. Knopf to WB, 19 Apr., 27 Sep. 1928, HHL.

WB to Higher Educational Authorities, Hamburg, 18 Sep. 1928, RS to ditto, same date, HO.

WB to Dean of the Mathematical-Physical Faculty, Hamburg University, 7 Dec. 1928 (endorsed as approved 12 Dec. 1928), HO.

Printed announcement of inaugural lecture, Hamburg University, 30 Jan. 1929, HO.

Schramm K.-J. , Die Sterne über Hamburg: Die Geschichte der Astronomie in Hamburg (book-length manuscript, 1994): RS, “Hamburg Bergedorf”, VJS, lxv (1930), 122–40.

WB, “Neuere Untersuchungen über extragalaktischen Sternsysteme” [typed 13-page manuscript], “After a lecture at the Scientific Researchers Day at Königsberg”, 8 Sept. 1930, HHL.

WB, “Über die Entfernungen und Dimensionen der extragalaktischen Nebel” [handwritten text for a lecture to the Naturwiss. Verein zu Hamburg], 19 Dec. 1927, HHL.

WB, “Der Nebel NGC II 1613”, AN, ccxxxiii (1928), cols 407–8; see also ref. 40.

WB, “Über einen bemerksamwerten neuen Nebelhaufen in Ursa Major”, AN, ccxxxiii (1928), cols 65–70.

See ref. 42.

WB, “Der kugelförmige Sternhaufen NGC 4147”, AN, ccxxxix (1930), cols 353–8.

WB, “Schwache Haufenveränderliche in hohen galaktischen Breiten”, AN, ccxliv (1931), cols 153–8. Baade had not mentioned finding any RR Lyrae variables in the Cygnus and Sagitta fields in his 1927 paper on them.

WB to HS, 8 Apr. 1930, HCO.

WB to [H]S, 15 Feb. 1930, HS to WB, 27 Feb., 22 Apr. 1930, HCO; see also ref. 65.

WB to [J. G.] Hagen, 15 Nov. 1929, 24 Jan. [1930], Vatican Observatory Archives, Vatican City.

WB, “Über den photographischen Lichtwechsel von Eros”, MHSB, vii (1930), 39; WB, “Bestimmung der photographischen und photovisuellen Helligkeit von Eros”, vii (1930), 87–88.

WB, “Beobachtungen des Pluto an Spiegelteleskop der Hamburger Sternwarte”, MHSB, vii (1931), 44.

Goos WB. F. Koch P. P. and Minkowski R. , “Die Intensitätsverteilen in den Spektralinien des Orion-Nebels”, ZfA, vi (1930), 87–88.

Zanstra H. , “An application of the quantum theory to the emission of light by diffuse nebulae” (ms.), July 1925, RAC; RS, “Hamburg Bergedorf”, VJS, lxvi (1931), 164–83; ibid., lxvii (1932), 199–214.

WB, “Über einen zweiten, sehr entfernen Nebelhaufen in Ursa major”, AN, ccxliii (1931), cols 107–10.

Humason M. L. , “The apparent radial velocities of 100 extra-galactic nebulae”, ApJ, lxxx (1936), 10–22.

WB, “Photographische Beobachtungen von Nebeln in Spiegelteleskop der Hamberger Sternwarte in Bergedorf”, AN, cccxliii (1931), cols 303–8.

WB, “Über der Periode von RV Canum ven”, AN, ccxliii (1931), cols 179–80.

WSA, “Memorandum regarding Dr. Baade of the Hamburg Observatory”, [∼15 Sep. 1930], HHL.

WSA to FER, 22 Dec. 1930, WB to [WS]A, 20 Jan. 1931, FER to WSA, 5 Feb. 1931, HHL.

WSA to WB, 2 Feb., 21 Mar. (telegram), 24 Mar. 1931; JCM to WSA, 25 Feb., 11 Mar. 1931; WSA to JCM, 21 Feb., 21 Mar. 1931; [W]B to [WS]A, 26 Mar. 1931 (telegram), HHL.

[JCM] to E. Hubble, 27 Apr. 1929, WSA to JCM, 19 Mar. 1934, JCM to WSA, 21 Mar. 1935, CIW; WSA to I. [S. Bowen], [∼5 Dec. 1947], CIT.

RS to the University Authorities, Hamburg, 25 Jan. 1930, HO.

WB to the University Authorities, Hamburg, 20 Apr. 1931, RS; idem, 20 Apr. 1931, Extract from proceedings of the Hamburg Senate, 22 June 1931, HO.

WB to [WS]A, 11 Apr. 1931; WSA to JCM, 30 Apr. 1931; WSA to WB, 18 May 1931, HHL.

JCM to WB, 23 May 1931; WB to [WS]A, 10 June, 22 July, 1931; WSA to WB, 30 June 1931; [WSA], “To whom it may concern”, 30 June 1931, HHL.

WB to [WS]A, 22 July 1931, HHL; “Prof. Dr. Baade departs for America”, Bergedorfer Zeitung, 1 Sep. 1931.