Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 151

Christian Mayer’s Double Star Catalog of 1779

J.S. Schlimmer Seeheim-Jugenheim, Germany

Email: [email protected]

Abstract: I discuss modern reviews of the first double star catalog in the history of astronomy by comparing the historical data set with current values or ephemeris.

Christian Mayer was a German astronomer, who initiated the construction of an astronomical observa- tory in the city of Mannheim in 1771. His observatory was completed in 1775 and Mayer began his observa- tions in January 1776 with a 2.5 inch achromatic telescope made by Peter Dollond in England. The focal length was about 8 feet and 1 inch. For his observations he used a power of 85. The telescope was mounted on an 8 foot mural quadrant made by John Bird also in England. It was Bird’s last mural quad- rant, see Figure 1. Figure 2 shows a part of Mayer's observation notes from January 24 and 25, 1776 after mounting the mural quadrant. Mayer’s interest was the study of the of the stars. During his observations, he often remarked on the stars that stood close together. During the time from 1776 to 1777 he found about 100 such close systems. He gives an account of his obser- vations in the academy in Mannheim in 1777. Mayer believed in the physical togetherness of such systems, called “Doppel(t)sterne”. His account was published in newspapers in different countries (Mayer, 1778). Figure 1: Mayer's mural quadrant from 1776. Photo: J.S. Schlim- Much criticism came from Maximilian Hell, a well mer, 2005 known astronomer, who lived in Vienna. It came to a public dispute between them, published in the news paper in Mannheim and Vienna. Hell’s opinion was stars was Mayer’s motive for publishing the first that the faint companions are background stars and double star catalog in history of astronomy. not physically connected with the brighter primary In its first version in 1779, the catalog included 72 stars (Mayer, 1778). At the end of their dispute, Hell double stars (Mayer, 1779). Two later, Mayer’s said, "Mayer shall compile a table with his double catalog was published in an astronomical circular by stars, so every astronomer can observe them when he the Berlin astronomer Johann Elert Bode, who added wants." Hell’s demand for a table of Mayer’s double 8 more well known double stars (Bode, 1781). In the Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 152

Christian Mayer’s Double Star Catalog of 1779

Figure 2: Mayer’s observation notes from January 24 and 25, 1776, photo: J. S. Schlimmer 2007

1781 version, the catalog included 80 double stars. Herschel measured the separation and the position The closest system was 5 epsilon Lyrae with a separa- angle directly in polar coordinates by comparing his tion of 2.9 arc seconds. It gives us a good impression of observation with the placement of his lamp microme- the quality of Mayer’s telescope. The minimum sepa- ter. In 1782 Herschel published his first double star ration of a perfect 2.5 inch reflector is about 1.7”. catalog in the Philosophical Transactions. William Herschel heard in 1779 about Mayer’s In Mayer’s catalog, often the stars had no name, work and started his own observations of double stars. but the coordinates for the of his observations His intention was not to study the proper motion, he 1777 and 1778 are described. Because the precession wanted to measure parallax (Herschel, 1782). Their of the earth's axis, the coordinates are obsolete. For method of operation in making their measurements example, gamma Arietis has moved 12 arc minutes in was very different. With a mural quadrant, differ- right ascension and 1 degree in declination. The first ences in declination were pick up directly, the differ- step of my review of Mayer’s catalog was to calculate ences in right ascension were measured with help of the current coordinates. With the, new coordinates an astronomical pendulum clock (Mayer, 1778). With many unnamed doubles could be identified. a declination of 0 degree, a star moves 15 arc second The second step of my review was to transform in one time second. In this way measurements were Mayer’s Cartesian coordinates into polar coordinates. done in Cartesian coordinates. In opposition to Mayer Because the way a star moves in time depends on its Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 153

Christian Mayer’s Double Star Catalog of 1779 declination, the calculations were done by the individ- References ual declinations of 1778. Mayer’s observation results could then be checked Gründliche Vertheidigung neuer Beobachtungen von by comparison with current values of separation and Fixsterntrabanten, welche zu Mannheim auf der angular position. Often there is no movement be- kurfürstlichen Sternwarte entdeckt worden sind,[ tween the companions and separation and position Defense of new Observations of Fixed Star Satellites], angle are the same as in 1778. However, for some Christian Mayer, Mannheim 1778 double star systems there is an orbit. With known orbital elements the position angle and separation De novis in coelo sidereo phaenomenis in miris stel- can be calculated for 1778 and used for comparison. In larum fixarum comitibus, Christian Mayer, Mann- some cases of components with equal brightness the heim 1779 position angles disagree by about 180 degrees. Verzeichniss aller bisher entdeckten Doppelsterne By checking Mayer’s values with data sets of The [Directory of all hitherto discovered doubled Washington Double Star Catalog, I often found entries stars], Berliner Astronomisches Jahrbuch für for 1777 with equal or similar values cited by 1784, Christian Mayer, published by Johann Elert Herschel, Lewis and Strand (Mason, et al. 2007). Bode, 1781 In the following table you’ll find my calculations based on Mayer’s observations of 1778 described in Catalog of Double Stars, William Herschel, Philoso- detail in his “Tabula Nova Stellarum Du- phical Transactions of the Royal Society of Lon- plicium” (Mayer, 1779). Mayer 8, Mayer 10, Mayer 15, don, 1782 Vol. 72 Mayer 32, Mayer 37, Mayer 48, Mayer 51 and Mayer On the Parallax of the Fixed Stars, William Herschel, 63 were not included in Mayer’s first catalogue of Philosophical Transactions of the Royal Society of 1779. The value of those stars were in the astronomi- London, 1782 Vol. 72 cal circular of Bode in 1781. In some cases, I couldn’t identify Mayer’s observa- Description of a Lamp-Micrometer, and the Method of tions. For Mayer 10, Mayer 16, Mayer 26, Mayer 27, using it, William Herschel, Philosophical Transac- Mayer 45, Mayer 53, Mayer 63, Mayer 69, Mayer 71, (Continued on page 158) Mayer 74 and Mayer 78 I give the double stars which best match Mayer’s transformed coordinates. In other cases like alpha Arietis or omega Piscis, the stars are not visual double stars. Figure 3 represents the relative error of Mayers distance measure- ments. In 12 cases the error is under 5%, in 7 cases the error lies between 5 and 10%, and in a further 14 cases the error lies between 10 and 20%. In some cases the relative error is explained by the independent movement of the components e.g. with Mayer 36. In other cases, for example with Castor (Mayer 21), incorrect time measure- ment of the distance in right ascension significantly affects the results. With a relative error of nearly 300%, Mayers measurements of 54 Virginis (Mayer 35) are the worst. Out of 57 measurements between 1777 and 2006 it follows that neither distance Figure 3: Relative error for Mayers' distance measurements for each double star nor position angle has changed. system in his catalog. Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 154

Christian Mayer’s Double Star Catalog of 1779

1,2 1 1 2 3 11 note - WDS mag. 7.25,7.43 5.27,5.45 5.22,6.15 6.65,9.51 4.52,4.58 4.80,6.65 2.31,5.02 2.0 6.50,7.02 5.5,9.8 6.58,6.93 4.24,7.02 6.06,7.43 3.76,6.56 3.76,6.34 2.41,6.83 9.43,9.77 4.62,5.00 6.31,6.88 7.17,7.41 1.93,2.97 5.05,6.20 6.16,6.21 - pa - 192 -5 4 -148 193 -1 -1 1 -102 -180 -4 -2 -49 -7 -1 -226 189 0 -182 -17 -1 .-84 diff - - pa 46 159 63 328 0 47 63 275 200 270 214 305 84 62 1 316 133 211 244 310 181 215 2007 - pa 238 154 67 180 193 46 62 276 98 90 210 303 36 55 0 90 310 322 211 62 293 180 131 1778 Table continued on next page. next on Table continued - - -1.2 2.2 1.0 -1.7 4.9 0.5 2.6 2.4 15.1 -2.7 3.3 12.4 -4.9 -3.3 2.5 2.5 -6.0 6.0 1.6 3.8 Sep. -79.8 Diff. -40.4 - - 47.1 30.3 23.3 5.9 7.6 38.2 9.6 39.0 62.6 11.6 63.0 40.3 13.4 41.5 53.3 94.8 7.1 19.7 53 3.6 6.1 5.0 Sep. 2007 - Sep. 1778 45.9 32.5 24.3 4.2 12.5 38.7 12.2 41.4 22.2 26.7 60.3 43.6 25.8 36.6 50.0 15.0 72.9 9.6 22.2 47.0 9.6 7.7 8.8 - - WDS 00464+3057 01057+2128 01137+0735 01269+0332 01535+1918 01579+2336 02039+4220 02370+2439 02004-0831 03313+2734 04422+2257 04590+1433 05387-0236 05387-0236 05320-0018 05441-0229 06288-0702 06323+1747 06341+2207 07346+3153 08122+1739 08268+2656 Identifier - - Code STFA 1 STFA 88ABSTF 100ABSTF 122 STF 180ABSTF H 5 12AB 205A-BC STF 5 STFA HJ 3476AB 401 STF 455Aa-B S 49ABSHJ 762AB,C STF 762AB,E STF 14Aa-C STFA 291.8A- A BC 919ABSTF 924ABSTF 524ABS STF1110AB STF1196AB-C STF1223 - Pisces ψ Current Current Arietis Gemini Orionis Orionis Arietis Arietis Piscis Piscis Cancri Orionis 94 Taurus Arietis Arietis Andromedae Description HIP3617 74 ζ 419 BSC γ λ γ α 30 Arietis 587 BSC 1065BSC τ 1600BSC σ σ δ 4771- TYC 01005-1 (11 Or. Einh.) 31158HIP 31323HIP α ζ Can- 2 Phi ceri Mayer’s Mayer’s Description Andromeda Androm. Fische zeta my bei Fische Widder Gamma Widder Lambda AndromedaGamma Widder Alpha 30 Widder Wahlfisch Stier Stiertau Stier Orion Orion Delta Zeta bei Orion Zwillinge (11 Or. Einh.) 30 Zwillinge Zwillinge Castor Krebs Zeta 2. Phi Krebs No. Mayer 1 Mayer 2 Mayer 3 Mayer 4 Mayer 5 Mayer 6 Mayer 7 Mayer 8 Mayer 9 Mayer 10Mayer 11Mayer 12Mayer 13Mayer 14Mayer 15Mayer 16Mayer 17Mayer 18Mayer 19Mayer 20Mayer 21Mayer 22Mayer 23Mayer Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 155

Christian Mayer’s Double Star Catalog of 1779

2 1 4 5 1 2 note - - WDS mag. 6.92,7.53 4.13,5.99 6.56,10.4 0 4.48,6.30 6.55,7.50 5.05,7.47 5.64,5.73 7.04,7.13 3.48,3.53 2.85,5.52 6.78,7.19 7.11,8.18 2.23,3.88 4.88,5.79 2.59,4.52 4.35,5.31 5.76,6.92 3.48,5.40 5.23,6.64 5.12,9.33 4.50,5.40 6.13,6.47 - - - - pa -50 -1 -216 -2 -99 -23 -73 -184 -3 232 -153 -5 16 -2 1 13 -172 34 -28 9 diff - - - pa 50 308 216 112 150 181 210 245 314 229 34 153 111 24 338 229 105 352 56 319 93 2007 - - pa pa 307 0 110 51 158 137 130 226 266 77 106 40 336 228 180 118 180 90 291 102 1778 Table continued on next page. next on Table continued - - - - -5.4 1.9 -14.0 0.7 0.3 -49.0 4.2 4.3 3.1 16.1 -13.9 1.9 2.3 0.8 1.2 4.0 3.7 3.5 -1.4 Sep. Diff. -222.3 - - 5.4 30.7 20 6.5 28.6 88.9 9.4 8.9 5.5 19.3 5.4 107.6 13.9 5.5 13.1 41.2 69.1 4.7 10.3 224.7 4.1 21.3 Sep. 2007 - - Sep. 1778 32.6 6.0 7.2 28.9 39.9 13.6 9.8 22.4 21.5 30.3 0.0 7.4 15.4 42.0 70.3 13.2 8.7 14.0 2.4 7.6 19.9 - - WDS 08267+2432 08467+2846 09123+1500 10556+2445 11268+0301 11279+0251 11323-2916 12207+2703 12417-0127 12560+3819 13134-1850 13149-1122 13239+5456 14407+1625 16054-1948 16120-1928 16406+0413 17146+1423 17180-2417 17209+2430 17237+3709 17446+0235 Identifier - - Code STF1224A-BC STF1268 569Aa-C STT STF1487 STF1540AB 19ABSTFA H 3 96 STF1633 STF1670AB STF1692 151 SHJ 162Aa-B SHJ STF1744AB STF1864AB 7AC 3 H 6Aa-C H 5 31Aa-BSTFA STF2140Aa-B H 25 3 687AB S STF2161Aa-B STF2202AB - Current Current Canis Ophiuchi Hercules 29 29 Bootes Scorpii Hercules Scorpii Ursa Leonis Virginis Virginis Canceri Description 24 Canceri ι TYC0825- 01529-1 54 Leonis 83 Leonis τ BSC4443 BSC4698 γ α Venatici 54 Virginis HIP64638 ζ Majoris π β ν 36 Hercules α α 39 Ophiuchi 70 (!) Hercules ρ 61 Ophiuchi Mayer’s Mayer’s Description Krebs, dunkel Krebs, iota Krebs bei pi Krebs bei pi Krebs 54 Löwe tau bei Löwe Nr. 83 tau Löwe Wasserschlange a Haar der Berenike Jungfraugamma Jagdhunde 12 Jungfrau 54 Jungfrau Zeta gr. Bären *) Bootes Pi Beta Scorpion Scorpion Ny im Herkules12 Ophiuch.alpha Herkulesalpha Ophiuch. 39 Herkules 71 Herkules roh Ophiuch. 61 No. Mayer 24Mayer 25Mayer 26Mayer 27Mayer 28Mayer 29Mayer 30Mayer 31Mayer 32Mayer 33Mayer 34Mayer 35Mayer 36Mayer 37Mayer 38Mayer 39Mayer 40Mayer 41Mayer 42Mayer 43Mayer 44Mayer 45Mayer 46Mayer 47Mayer Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 156

Christian Mayer’s Double Star Catalog of 1779

1 2 1 2 6 7 1 8 note - - WDS mag. 3.98,7.21 4.85,5.20 5.07,5.74 5.81,5.84 7.48,10.22 6.86,7.63 4.34,5.62 5.15,6.10 5.25,5.38 3.63,6.69 4.59,4.93 4.38,8.58 3.19,4.68 7.38,10.74 5.91,6.68 7.12,7.39 8.35,8.42 4.36,5.03 5.30,7.05 7.38,10.74 5.35,6.10 7.61,9.57 - - - pa pa 3 -250 -3 84 -51 -2 7 25 2 2 9 0 -156 3 -152 -41 12 11 -210 3 169 diff - - pa pa 76 257 340 183 6 51 150 31 155 149 104 81 54 336 239 255 290 266 67 336 48 11 2007 - pa 90 260 90 180 90 0 148 38 180 151 106 90 54 180 242 103 249 278 78 126 51 180 1778 Table continued on next page. next on Table continued - - - 2.0 2.9 3.2 -3.3 -7.6 1.7 0.4 -0.4 1.0 0.4 -5.1 -1.4 -22.9 3.0 -2.6 4.3 8.4 3.1 -14.6 1.5 Sep. Diff. -105.6 - - 28.6 6.5 3.1 14.3 3.3 17.5 43.6 3.4 2.9 47.4 23.0 28.6 35.3 29.9 22.6 17.8 25.2 9.1 10.7 29.9 13.8 111.6 Sep. 2007 - Sep. 1778 1.4 8.5 7.6 17.5 0.0 9.9 2.0 45.3 3.8 2.5 48.4 23.4 23.5 33.9 7.0 25.6 15.2 29.5 17.5 13.8 15.3 15.3 6.0 - - WDS 19226-4428 18015+2136 16256-2327 18078+2606 18157-0321 18187-1837 18448+3736 18443+3940 18443+3940 18501+3322 18562+0412 19138+3909 19307+2758 21050+3526 20299-1835 20312+1116 20368+1444 20467+1607 20591+0418 21050+3526 21069+3845 21091+3844 Identifier - - Code DUN 226 DUN STF2264 H 2 19AB STF2280Aa-B STF2296 264AB-CSHJ 38AD STFA STF2382AB STF2383Cc-D STF 39AB STF2417AB STF2487AB 43Aa-B STFA STF2753 324 SHJ STF2690Aa-BC STF2703AB STF2727 STF2737AB-C STF2753 STF2758AB S 779 - Lyrae Lyrae Current Current ε ε Capricor- Lyrae Sagittarius Ophiuchi Lyrae Lyrae Lyrae Lyrae Serpentis Equuleus Delphinus Description Description β Her 95 ρ Her 100 HIP89489 BSC6848 Serpentis 61 ζ 4 5 β θ η β HIP104064 ω nus BSC7840 HIP101698 γ ε HIP104064 Cygni61 HIP104417 Mayer’s Mayer’s Description Description b Schützen Oph.beim Herkul. Ophiuchi rho Herkules Schlange Schütze Ophiuchus Leyerzeta Leyerepsilon Leyer5. Leyerbeta Schlange theta Leyer eta Schwanbeta Schwan gamma bei Steinbock omega Delphin beta über Del- phin Delphingamma Füllenbeim Schwan Schwan Schwan No. Mayer 48Mayer 49Mayer 50Mayer 51Mayer 52Mayer 53Mayer 54Mayer 55Mayer 56Mayer 57Mayer 58Mayer 59Mayer 60Mayer 61Mayer 62Mayer 63Mayer 64Mayer 65Mayer 66Mayer 67Mayer 68Mayer 69Mayer 70Mayer 71Mayer Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 157

Christian Mayer’s Double Star Catalog of 1779

Description : 9 2 10 note Column 1 : Number from (Bode, 1781) Column 2 : Mayer’s Description from (Bode, 1781) Column 3 : Current Description from (Hoffleit, - WDS mag. 1991) and Redshift 5

4.75,6.18 7.21,7.73 5.27,5.45 7.60,8.17 7.21,7.67 7.77,8.37 8.25,10.37 6.46,6.72 Column 4 : Code from Washington Double Star Catalog - - - - pa 0 18 65 3 1 diff Column 5 : Separation for 1778 from (Mayer,1779) except note 1 - pa

109 57 156 177 151 184 334 179 Column 6 : Current separation from Washington 2007 Double Star Catalog except note 3,4,6-10,11 - - - -

pa pa Column 7 : Separation differences = Column 5 – 109 75 221 180 180 1778 Column 6

- - - - Column 8 : Position angle for 1778 from (Mayer, 4.3 4.6 -25.7 1.6 0.6 Sep. Diff. 1779), except note 1 Column 9 : Current position angle from Washington - Double Star Catalog, except note 3,4,6-10,11 6.9 10.9 30.3 24.4 6.3 10.4 36.5 3.7 Sep. 2007 Column 10: Position angle differences = Column 8 – Column 9 - - - Sep. 1778 11.2 15.5 4.6 26.0 0.0 4.3 Column 11: Brightness from Washington Double Star Catalog Column 12: Notes - WDS 21441+2845 21580+0556 01057+2128 23141-0855 23238-0828 23307+0515 23543+3154 23595+3343 Identifier Notes: 1. Published first in Bode’s astronomical yearbook in 1781

- 2. No double star Code 3. Ephemeris for 1778, Doc1985 STF2822AB STF2848 88AB STF STF2993AB STF3008 STF3019 358 SHJ STF3050 4. Ephemeris for 1778, Sca2006b 5. The proper motion is 0.37"/year 6. Ephemeris for 1778, Nov.2006e Pisces

ψ 7. Ephemeris for 1778, Doc1984b Current Current Piscis Cygni Description Description μ 208718HD 74 HIP114702 220436HD HIP116035 TYC2772- 00004-1 ω BSC9075 8. Ephemeris for 1778, Kis1997 9. Ephemeris for 1778, Hei1995 10.Ephemeris for 1778, Sta1977b 11.Ephemeris for 1778, Hei1996b Mayer’s Mayer’s Description Description my Schwan Wassermann Wassermann Zeta Wassermann Wassermann Fische Andromeda Fischeomega Andromeda No. Mayer 72Mayer 73Mayer 74Mayer 75Mayer 76Mayer 77Mayer 78Mayer 79Mayer 80Mayer Vol. 3 No. 4 Fall 2007 Journal of Double Star Observations Page 158

Christian Mayer’s Double Star Catalog of 1779

(Continued from page 153) tions of the Royal Society of London, 1782 Vol. 72 Bright , 5th Revised Ed. (Preliminary Version), Hoffleit+, 1991, Yale University Obser- vatory, http://www.alcyone.de/SIT/bsc/index.html The Washington Double Star Catalog, Brian D. Ma- son, Gary L. Wycoff, and William I. Hartkopf, 2007, http://ad.usno.navy.mil/wds/ Redshift 5, Maris Technologies, United Soft Media GmbH, http://www.redshift.de/us/_main/index. htm