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1926AJ. the ASTRONOMICAL JOURNAL. 143 •Nos os UD•N - 857-858 THE ASTRONOMICAL JOURNAL. 143 00 TRIGONOMETRIC PARALLAXES OF FORTY SEVEN STARS, DETERMINED BY PHOTOGRAPHY WITH THE 26-INCH MCCORMICK REFRACTOR 1926AJ. By S. A. MITCHELL This list of parallaxes is in continuation of those Mr. Michel Kovelenko measured the plates on published in Astronomical Journal, Nos. 778; 796, 803, stars numbered 617, 636, 645 and 647; Dr. P. van de 808, 824, 840 and 851. The details of the observa- Kamp those numbered 635, 642, 643 and 644. The tions will appear as a Memoir of the National Academy latter also partially measured the plates on v Cor once of Sciences under the title “Trigonometric Parallaxes Borealis. Dr. Harold L. Alden measured the plates of Four Hundred and Forty Stars.77 The volume of a Geminorum. which is now in press should appear without undue For reasons which are stated in the forthcoming delay and it will bring the number of the McCormick publication, four of the regions of the present list are published for the second time, the photographs being parallaxes published to the total of seven hundred. entirely different from the original series. These In the Table below, in the column of proper motions four are the bright doubles Castor and y Leonis, the 77 under “Boss the designation of an asterisk (*) signi- interesting binary 9 Argus and W.B. 10h 234. The fies that the value is taken from Cincinnati Publica- mean of the two series of plates of Castor give the tions No. 18. relative parallax +0,/.067 ^".OOö. Magnitude Proper Motion R. A. Decl. Parallax No. Star 1900 1900 and Right Ascension M Spectrum Total Boss I Observed Relative Absolute 607 Boss 189 0 47.1 +60 34 4.9 F8 0.188 -.073 -.075 +.061 ±.009 + .064 + 3.9 608 K Persei 3 2.7 +44 29 4.0 K0 0.240 + .182 + .199 + .010 12 + .013 -0.4 609 Ç Persei 3 47.8 + 31 35 2.9 Bl 0.021 + .013 -.035 -.007 11 610 39 Tauri 3 59.4 + 21 44 6.0 G5 0.222 + .174 + .167 + .077 9 + .080 + 5.5 611 ß Camelop 4 54.5 +60 18 4.2 GOp 0.013 + .002 -.012 + .011 11 + .014 -0.1 612 ß Orionis 5 9.7 - 8 19 0.3 B8p 0.005 + .001 -.002 + .002 9 + .006 -5.8 613 rj Orionis 5 19.4 - 2 29 3.4 Bl 0.006 + .006 -.026 + .020 7 + .023 +0.2 614 X Orionis Br. 5 29.6 + 9 52 3.7 Oe5 0.011 + .001 -.001 + .010 8 + .013 -0.7 615 X Orionis Ft. 5 29.6 + 9 52 5.6 B2 0.011 + .001 -.029 -.006 11 -.003 616 f Orionis 5 35.7 -20 2.0 B0 0.012 + .007 + .003 + .020 8 + .023 -1.2 617 v Aurigœ 5 44.6 + 39 7 4.2 K0 0.008 -.005 -.047 + .006 10 + .009 -1.0 618 d Aurigœ 5 52.9 + 37 12 2.7 AOp 0.106 + .054 + .069 + .025 8 + .028 -0.1 619 a1 Geminorum 7 28.2 + 32 6 2.8 A0 0.204 -.172 -.167 + .053 11 + .057 +2.1 620 a2 Geminorum 7 28.2 + 32 6 2.0 A0 0.204 -.172 -.214 + .062 10 + .066 + 1.3 621 W. B. 7h 1029 7 38.2 + 39 50 6.8 F8 0.685 + .057 + .051 + .011 11 + .015 +2.7 622 9 Argus 7 47.1 -13 38 5.3 GO 0.342 -.060 -TOO + .028 8 + .031 +3.0 623 Lalande 15389 7 47.9 -13 36 6.9 K0 + .055 -.016 10 -.013 624 W. B. 10h 234 10 14.2 + 20 23 9.2 Map 0.490 -.488 -.436 + .176 9 + .181 + 7.7 625 7 Leonis, Br. 10 14.5 + 20 21 2.6 G8 0.347 + .303 + .339 + .020 8 + .026 -0.3 626 7 Leonis, Ft. 10 14.5 + 20 21 3.8 G5 0.347 + .303 + .326 + .019 10 + .025 +0.9 7 Leonis, Mean 10 14.5 + 20 21 + .020 6 + .026 627 L Virginis 14 10.8 - 5 31 4.2 F5 0.427 -.018 + .002 + .025 13 + .030 + 1.6 628 Lalande 14 17.6 +30 6 8.6 K6 0.727 -.641 -.607 + .069 9 + .076 +8.0 620 y Coronœ Bor. 15 19.1 + 30 39 5.6 GO 0.237 + .129 + .151 + .047 12 + .053 + 4.2 630 v1 Coronœ Bor. 16 18.6 + 34 2 5.4 Ma 0.049 + .005 -.015 + .012 14 + .017 + 1.6 © American Astronomical Society • Provided by the NASA Astrophysics Data System 143M . os 144 THE ASTRONOMICAL JOURNAL. N - 857-858 36. Magnitude Proper Motion R. A. Decl. Parallax No. Star 1900 1900 and Right Ascension M Spectrum Total Boss f Observed Relative Absolute v1 Coronœ Bor. 1926AJ 631 16 18.7 +33 56 5.3 K5 0.055 + .004 -.004 + .011 14 + .016 + 1.3 632 Lalande 30271 16 32.5 +31 9 7.3 F8 0.482 -.010 + .007 + .042 8 + .046 + 5.6 633 W. B. 16h 964 16 32.9 +31 18 9.5 K5 0.59 + .340 + .335 + .051 10 + .055 +8.2 634 i Herculis 17 36.6 +46 4 3.8 B3 0.008 -.008 -.017 -.006 11 -.002 635 y Ophiuchi 17 42.9 + 2 45 3.7 A0 0.084 -.027 -.039 + .004 8 + .007 -2.1 636 £ Draconis 17 51.8 +56 53 3.9 K0 0.126 + .098 + .093 + .041 7 + .045 +2.2 637 72 Ophiuchi 18 2.6 + 9 33 3.7 A3 0.100 -.062 -.080 + .030 11 + .033 + 1.3 638 Lalande 33439 18 6.4 +38 28 6.4 KO 0.58 -.352 -.318 + .106 12 + .110 + 6.6 639 1 Aquilœ 18 29.8 - 8 19 4.1 KO 0.318 -.022 -.030 + .021 11 + .024 + 1.0 640 Boss 4837 18 56.9 + 75 39 7.0 AO 0.023 + .019 + .051 -.006 9 -.002 641 Boss 4838 18 56.9 + 75 39 6.7 AO 0.030 + .018 + .003 -.014 -.010 642 6 Lyrœ 19 12.9 +37 57 4.5 KO 0.010 -.010 -.007 + .009 10 + .012 -0.1 643 K Cygni 19 14.8 + 53 11 4.0 KO 0.285 + .064 + .085 + .006 10 + .009 -1.2 644 y Cygni 19 52.6 + 34 49 4.0 KO 0.052 -.034 -.042 + .004 10 + .007 -1.8 645 27 Cygni 20 2.7 + 35 42 5.5 KO 0.494 -.232 -.237 + .031 + .034 + 3.2 646 P Cygni 20 14.1 + 37 43 4.9 Bip 0.014 -.012 + .022 + .009 11 + .012 + 0.3 647 47 Cygni 20 30.0 +34 54 4.8 K5 0.015 -.002 + .044 -.003 14 .000 648 a Delphini 20 35.0 + 15 34 3.9 B8 0.064 + .064 + .057 + .017 11 + .020 + 0.4 649 A. Oe. 21308 21 14.6 -20 15 9.2 K5p 0.76 -.182 -.176 + .034 10 + .039 + 7.2 650 A. G. Leipzig 8693 21 46.2 + 12 9 7.6 Bip -.054 + .004 10 + .008 + 2.1 651 51 Pegasi 22 52.5 +20 14 5.6 GO 0.213 + .204 + .182 + .073 9 + .077 + 5.0 652 Lalande 45755 23 16.7 +43 32 7.6 G5 0.67 + .631 + .623 + .052 11 + .055 + 6.3 653 A. Oe. 25685 23 26.5 + 58 37 6.8 KO 1.06 + 1.052 f 1.102 + .021 9 + .024 + 3.7 Leander McCormick Observatory, University of Virginia, January 9, 1926. OBSERVATIONS OF THE SOLAR ECLIPSE, 1926 JANUARY 14, By T. P. BHASKARAN. The following observations of the Solar Eclipse 1926 First Contact Jan. 14, were made at the Nizamiah Observatory, Time Instrument Observer Hyderabad. llh4m7s.8 3// telescope (Projection) M. K. Bappu The times given are in Indian Standard Time Last Contact which is hours in advance of Greenwich Mean 13h2m7s.4 15" Equatorial (aperture T. P. Bhaskaran Time. stopped to 6 colored glass over eyepiece) Nizamiah Observatory, Hyderabad—Deccan, India. 13h2m6s.4 3" telescope (Projection) M. K. Bappu CONTENTS. The Corrections to the Declination System of Boss’ Preliminary General Catalogue, by H. Raymond. The Solar Motion Problem, by Ralph E. Wilson. Progressive Changes in Mean Latitude, by Ralph E. Wilson. Trigonometric Parallaxes of Forty Seven Stars, by S. A. Mitchell. Observations of the Solar Eclipse, 1926 January 14, by T. P. Bhaskaran. Editor, Benjamin Boss, Albany, N. Y.; Associate Editors: Ernest W. Brown and F. R. Moulton. Published by the Dudley Observ- atory, Albany, N. Y., U. S. A., to which all Communications Should Be Addressed. Price $5.00 the Volume. Press of Thos. P. Nichols & Son Co., Lynn, Mass. Closed, March 10, 1926. © American Astronomical Society • Provided by the NASA Astrophysics Data System .
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