Walter Baade,Obervational Astrophysicist,(2): Mount Wilson 1931–1947

DEO, “Walter Baade, observational astrophysicist, (1): The preparation”, JHA, xxvi (1995), 1–32.

WSA, “Annual report of the director”, CIW, xxxi (1932), 135–72.

WB to [H]S, 15 Mar. 1937, HCO.

Some of Baade's unexpurgated statements about Hubble's hopeful treatment of magnitude scales are preserved in WB, Evolution of stars and galaxies (Ann Arbor, 1980), a facsimile reprint of the mimeographed notes from a graduate course he gave at Harvard in 1958, prepared at the time by R. B. Rodman from a tape recording.

Baade's progress is briefly described in successive annual reports, similar to the one for 1931–32 cited in ref. 2, WSA, “Annual report of the director”, CIW, xxxii (1933), 127–65; xxxiii (1934), 125–57; xxxiv (1935), 157–90; xxxv (1936), 157–94. These annual reports, drawn up by Adams on the basis of draft paragraphs and sections prepared by individual staff members like Baade, are full of information and are used throughout this paper without being referenced each time.

WSA, ibid., xxxvi (1937), 3–39; xxxvii (1938), 2–32; xxxviii (1939), 3–31.

HS to WB, 3 Mar. 1937, HCO.

JS to WB, 23 Nov. 1935, 19 Nov. 1942, UWA.

WB to [NU]M, 19 Nov. 1945, SLO; WB to [IS]B, 12 Sep. 1946, HHL.

WSA, “Annual report of the director”, CIW, xxxix (1940), 3–26.

WB to [NU]M, 10 May 1936, SLO.

WB, “The distance of the globular cluster NGC 5694”, PASP, xlvi (1934), 52–53.

WB, “The globular cluster NGC 2419”, ApJ, lxxxii (1935), 396–412; HS to WB, 4 Feb. 1935, HCO.

WB, “A new, very distant cluster-type variable”, PASP, xlviii (1936), 274–6.

WB to [RS], 21 Oct. 1935; [RS] to WB, 18 Nov. 1935; HO.

WB, “The distance of the Cygnus cloud”, ApJ, lxxix (1934), 475–82.

See ref. 1.

Curtis H. D. , “The nebulae”, Handbuch der Astrophysik (Berlin), v/2 (1933), 774–936.

WB and FZ, “On super-novae”, PNAS, xx (1934), 254–9.

WB and FZ, “Cosmic rays from super-novae”, PNAS, xx (1934), 259–63.

WB and FZ, “Remarks on super-novae and cosmic rays”, Physical review, xlvi (1934), 76–77.

EH and G. Moore, “A super-nova in the Virgo cluster”, PASP, xlviii (1936), 108–10.

Anderson J. A. to Hale G. E. , 5 Oct. 1931, George Ellery Hale Papers, microfilm edition.

Müller R. , Fritz Zwicky: Leben und Werk des grossen Schweizer Astrophysikers, Raketenforschers und Morphologen (Glarus, 1986). This is by far the best source for an outline of the subject's life and career, but any statement in it based on retrospective writings by Zwicky himself must be taken with a large grain of salt, if it is not corroborated by contemporary written evidence. The author reveals this indirectly many times in the book, not in the text itself but in the references in the appendix. Several more discrepancies have turned up, in the research for the present paper, between Zwicky's later statements and written letters from the 1930s in archives cited.

WB to [RS], 7 June 1935, [RS] to WB, 19 Aug. 1935, HO.

WB to [RS], 28 July 1936, HO; C. F. J. Overhage and FZ, “Some magnitudes of nova 618.1936 Aquilae (I)”, PASP, xlviii (1936), 321–3; WB and FZ, “Photographic light-curves of the two supernovae in IC 4182 and NGC 1003”, ApJ, lxxxviii (1938), 411–21.

FHS to FZ, 31 Aug. 1937, HHL.

HS to W[B], 19 Aug., 4 Sep. 1936, HCO; FZ to CPG, 8 Aug. 1936, Müller , op. cit. (ref. 24), 153. I have not had access to this letter, which Shapley and Müller describe; Müller quotes directly the one sentence from it which I have quoted in the text, translated back into the English in which Zwicky presumably wrote it.

CPG, “On the physical condition of the supernovae”, PNAS, xxii (1936), 332–6; FZ, “Characteristic temperatures in super-novae”, PNAS, xxii (1936), 557–61.

FZ, “On the frequency of supernovae”, ApJ, lxxxviii (1938), 529–41.

WB, “Further notes on the super-nova in NGC 4273”, PASP, xlviii (1936), 226–9; WB. “The absolute photographic magnitude of supernovae”, ApJ, lxxxviii (1938), 285–304.

DEO, “Nicholas Ulrich Mayall”, BMNAS, lxix (1996), 189–212.

WB to [NU]M, 15 May, 30 June 1936, 13 Jan. 13 Mar. 1937, SLO, are just a few of the early examples of such letters.

WB to [NU]M, 16 Jan. 1937, SLO.

NUM, “The spectrum of the Crab nebula in Taurus”, PASP, xlix (1937), 101–5.

WB to [NU]M, 3 Nov., 10 Nov. 1938, SLO; NUM, “The Crab nebula, probable supernova”, ASP leaflets, iii (1939), 145–54.

DEO, “Rudolph Leo Minkowski”, BMNAS, liv (1983), 271–98; Th. Schmidt-Kaler, “Rudolph Minkowski”, Sterne und Weltraum, xxxiv (1995), 436–40. Minkowski's first name was Rudolf, in the German spelling, until 1938 when he Americanized it to Rudolph, but I have used the later spelling throughout.

WB to [WS]A, 15 June 1933, HHL.

W. E. Tisdale memorandum, 24 July 1933, WSA to MM, 31 July 1933, RAC.

RM to [WS]A, 20 July 1933, MM to WSA, 13 Oct. 1933, R. Ladenburg to WSA, 1 May 1934, WSA to MM, 24 May 1934, ERM to WSA, 21 July, 19 Sep. 1934, WSA to ERM, 27 Sep. 1934, HHL.

ERM to WSA, 19 Oct. 1934, WSA to W. Weaver, 26 Oct. 1934, Weaver to WSA, 1 Nov., 16 Nov. 1934, RM to WSA, 25 Feb. 1935, HHL.

ERM to WSA, 17 May 1934, FHS to JCM, 27 May, 3 June (telegram and letter) 1935, JCM to FHS, 29 May, 31 May (both telegrams), 31 May (letter) 1935, R. F. Hanson to JCM, 24 June 1935, JCM to Hanson, 13 July 1935, WSA to JCM, 9 Aug. 1935, HHL.

WB and RM, “The spectrum of comet Peltier (1935a)”, PASP, xlviii (1936), 277–8.

WB and RM, “The Trapezium cluster of the Orion nebula”, ApJ, lxxxvi (1937), 119–22; WB and RM, “Spectrophotometric investigations of some O- and B-type stars connected with the Orion nebula”, ApJ, lxxxvi (1937), 123–35.

WSA to Director, Emergency Committee, 25 Mar. 1936, J. Whyte to WSA, 10 Apr., 14 May 1936, WSA to Whyte, 30 Apr. 1936, WSA to JCM, 18 May 1936, HHL.

WSA to JCM, 14 Jan., 3 May 1937, JCM to WSA, 8 Mar 1937, HHL.

WSA to JCM, 11 Apr., 25 Apr., 17 May 1938, JCM to WSA, 14 Apr., 5 May 1938, HHL.

RM, “The spectra of the supernovae in IC 4182 and NGC 1003”, ApJ, lxxxix (1939), 156–217.

RM, “Spectra of the supernova in NGC 4275”, PASP, lii (1940), 206–7, and “Spectra of supernovae”, PASP, liii (1941), 224–5.

WMG to WSA, 19 Dec., 26 Dec. 1942, 5 June 194[2], WSA to WMG, 22 Dec. 1941, HHL.

WB to [RS], 22 Oct. 1934, 1 Apr. 1935, HO.

RS to [W]B, 13 May, 14 May 1935, WB to [RS], 7 June 1935 (second letter of this date), HO.

WB to [RS], 21 Oct. 1935, 21 July 1936, HO.

RS to Prof. Backer, 23 Jan. 1936, WB to [RS], 24 Mar. 1936, RS to [R.] Mentzel, 6 Apr. 1936, Lecture announcement for 14 Feb. 1936, HO.

RS to [W]B 14 June, 30 Sep., 15 Nov. 1936, WB to [RS], 7 Dec. 1936, HO.

WSA to JCM, 29 Sep., 7 Oct. 1936, JCM to WSA, 1 Oct. 1936, HO.

WB to [RS], 7 Oct. 1936, HO.

WB to [RS], 24 Jan. (cablegram), 2 Mar. (cablegram and letter), 22 Mar., [15] Apr., 30 May 1937, [RS] to [W]B, 25 Jan., 15 Apr., 24 Apr., 29 Apr., 24 June, 1937, HO.

WSA to MM, 6 July 1937 (telegram), 10 July 1937, MM to WSA, 7 July (telegram) 1937, WSA to JCM, 7 July, 19 July, 28 July, 16 Aug. 1937, JCM to WSA, 8 July, 9 July, 21 July, 1 Aug. 1937, G. L. Streeter to WSA, 20 Aug. 1937, HHL.

[W]B to [RS], 19 July [1937] (cablegram), RS to [W]B, 20 July 1937, HO.

WSA to RS, 19 July 1937, HHL.

WB to Councilor Niemann, 29 July 1937, WB to [RS], 4 Aug. 1937, 13 Mar. 1938, WB and Hanni Baade to [RS], 10 Aug. 1937, HO; GPK to “Dear Colleague”, 14 June 1946, YOA. Kuiper was a member of the ALSOS mission, which followed close behind the Allied armies, debriefing and interrogating many Dutch and German astronomers and physicists during and immediately after the war. This letter summarizes his observations that there were no anti-Nazi astronomers left, except K.-O. Kiepenheuer.

[NUM] to WB, 19 Oct. 1937, 8 Mar. 1938, WB to [NU]M, 24 Oct., 24 Nov. 1937, 14 Jan., 11 Mar., 18 May, 26 May 1938, SLO.

WB, “Stellar photography in the red region of the spectrum”, PAAS, ix (1939), 31–32.

WB to [RS], 12 July 1938, [R]S to [W]B, 14 July 1938, HO; WB, [Untitled report on the advantages of the new red-sensitive plates], Transactions IAU, vi (1939), 452–3.

WB to [FH]S, 31 Aug. 1938, WB to [WS]A, 11 Sep. 1938, HHL; WB to RS, 26 Sep. 1938, HO.

HS to WB, 2 Nov. 1938, HCO.

WB to [O]S, 28 Nov. 1938, YOA; WB to RS, 8 May 1939, HO; Evans D. S. and Mulholland J. D. , Big and bright: A history of McDonald Observatory (Austin 1986).

WB, “Paper at dedication of the McDonald Observatory”, [∼Apr. 1939], [hand written text (in parts) and notes (in other parts)], HHL.

WB to [NU]M, 20 May 1939, SLO; JHO to AHJ, 23 Dec. 1939, HHL; WB to [JH]O, 17 Oct. 1940, 6 Oct. 1941, [JHO] to WB, 23 June, 22 Nov. 1941, AIP.

WB to RS, 13 July 1939, HO; WB to E. P. Varela, 5 June 1939, CIW; WB to [H]S, 1 Sep. 1939, HCO; “Programme du Colloque de la Foundation Singer-Polignac, Paris, Juillet 1939”, HHL.

WB, “Supernovae”, in Shaler A. (ed.), Novae and white dwarfs (Paris 1941), 177–96.

WB to WSA, 22 July 1939, HHL; WB to RS, 31 July, 4 Aug., 15 Aug., 8 Nov. 1939, RS to [W]B, 24 Aug., 10 Nov. 1939, HO.

WB to [O]S, 24 July 1940, OS to WB, 6 Aug. 1940, YOA; WB to [WH]W, 27 July 1940, JHM to WB, 30 July 1940, WHW to WB, 6 Aug. 1940, SLO.

WB to [GP]K, 17 Sep. 1940, 28 Nov. 1941, 10 Apr., 17 June 1942, [GPK] to WB, 27 Dec 1940, 31 Mar. 1942, UAL; WB to [O]S, 9 Oct. 1940, OS to WB, 14 Oct., 19 Oct. 1940, YOA.

WB, “Nova Herculis 1934 — the nebula and central star”, PASP, lii (1940), 386–8; WB, “The expanding shell around the nova Herculis”, PASP, liv (1942), 244–9.

JHO to WHW, 13 May, 20 June, 24 July 1939, WHW to JHO, 22 June, 1 July, 26 Aug. 1939, WB to [NU]M, 19 Oct. 1940, 27 Feb. 1941, SLO.

JHO to NUM, 22 July, 26 July, 6 Sep. 1940, 16 Jan., 6 May, 26 June, 28 Sep. 1941, 30 Aug. 1945, NUM to JHO, 2 Oct. 1940, 27 May, 3 Dec. 1941, SLO; Duyvendak J. J. L. , “Further data bearing on the identification of the Crab nebula with the supernova of 1054 A.D. Part I. The Chinese records”, PASP, liv (1942), 91–94; NUM and JHO, “Part II. The astronomical aspects” PASP, liv (1942), 95–104.

WB, “The Crab nebula”, ApJ, xlvi (1942), 188–98; RM, “The Crab nebula”, ApJ, xlvi (1942), 199–213.

WB to [NU]M, 13 Nov., 27 Nov., 6 Dec. 1941, 14 Jan., 29 Jan. 1942, SLO.

WB, “Brightness and lightcurve of Nova Ophiuchus (1604)” [his undated, handwritten, careful notes, all in German, on the “primary observations”, containing long passages copied out in Latin and Italian with various phrases underlined for emphasis], [c. 1937?], HHL; WB, “Nova Ophiuchi of 1604 as a supernova”, ApJ, xcvii (1943), 119–27; WB, “B Cassiopeiae as a supernova of type I”, ApJ, cii (1945), 309–17.

EH, “Problems of nebular research”, Scientific monthly, li (1940), 391–408; EH, “Zwicky's systems in Sextans and in Leo”, Scientific monthly, lii (1941), 486; FZ, Catalogue of selected compact galaxies and of post-eruptive galaxies (Guemlingen, 1976). The phrases quoted in the text are sample “descriptions” from this last book. See also ref. 24, which however downplays Zwicky's hostilities and outbursts.

HS, “A stellar system of a new type”, HCO bulletin , no. 908 (1938), 1–11; HS, “Two stellar systems of a new kind”, Nature, cxlii (1938), 715–16.

WB to [H]S, 2 Feb. 1939, HCO.

WB and EH, “Two new stellar systems in Sculptor and Fornax”, PASP, li (1939), 40–44. EH to V. M. Slipher, 11 June 1941, HHL states very clearly Hubble's position on observers producing data and “theoretical men” speculating.

E. Schoenberg to WB, 13 July 1939, K. Wurm to WB, 18 July 1939, HHL.

WSA to VB, 6 Apr. 1942, VB to WSA, 8 Apr. 1942, WSA “To Whom It May Concern”, 8 Apr. 1942, FHS to ditto, 8 Apr. 1942, WSA to Selective Service Draft Board, Altadena, 9 Apr. 1942, WSA to Col. Severin, 30 Apr., 14 May 1942, 100-inch Telescope Logbooks 1 and 2, HHL; GPK to OS, 17 May 1942, YOA.

WB, “The resolution of Messier 32, NGC 205, and the central region of the Andromeda nebula”, ApJ, c (1944), 137–46; WB, “NGC 147 and NGC 185, two new members of the local group of galaxies”, ApJ, c (1944), 147–50.

WB to [H]S, 14 Aug., 28 Aug. 1942, 20 Apr. 1943, HS to WB, 25 Aug., 2 Sep. 1942, 9 Apr., 28 July, 18 Oct. 1943, MLH to HS, 28 Feb. 1944, HCO.

JHM to NUM, 19 July, 14 Oct. 1943, 11 Jan, 11 Mar. 1944, NUM to [JH]M, 7 Oct. 1943, 5 Jan., 17 Jan. 1944, WB to [JH]M, 19 Oct. 1943, SLO.

WB to [O]S, 26 June, 8 July, 31 Aug. 1944, OS to WB, 1 July, 12 July, 6 Sep. 1944, YOA.

WB, “The globular clusters NGC 5634 and NGC 6229”, ApJ, cii (1945), 17–25.

WB to [W.] Dieckvoss, 26 Sep. 1945, HHL.

WB, “A search for the nucleus of our Galaxy”, PASP, lviii (1946), 249–52.

Sanford R. L. , “Reno meeting of the Astronomical Society of the Pacific”, PASP, viii (1946), 236–8; Anon., “New members [of the ASP]”, PASP, xlv (1933), 78.

ISB to WB, 4 Jan. 1946, HHL.

WB to [NU]M, 3 Oct., 10 Oct., 18 Oct., 4 Nov. 1946, 9 Jan., 12 July, 31 July, 25 Aug., 23 Sep., 6 Oct., 23 Oct. 1947, SLO.

WB, “Population II; 1947 Group meeting (January); Journal Club; Structure of our Galaxy (comparison with M 31)”, [Notes for four different talks, one dated “Journal Club 1947 April 30”, another clearly from 1946 from an internal reference, fourth probably also for 1947], HHL.

WB, [Survey of the problem of the two stellar populations], [1947], 15 hand-written pages of text of his invited talk.

Gingrich C. H. , “The seventy-fifth meeting of the American Astronomical Society”, PA, lvi (1948), 59–63; Gossner J. L. and Gossner S. D. , “Columbus meeting”, Sky & telescope, vii (1948), 91–93. The abstracts of many of the papers, including CPG's and RM's, are printed in AJ, liii (1948), 193–207, but not WB's.

WB to F. L. Whipple, 2 July 1947, HHL.