1996AJ 111 . 1 615E 1 THE ASTRONOMICALJOURNALVOLUME111,NUMBER4APRIL1996 plicity, anddemographics—thesolarmotion,doublestars, present centurysiderealastronomyconsistedofbutthree navigational needsofseveralmaritimestatesandanobvious chief beneficiarywastheaccuracyandscopeofpropermo- this motionwasdependentuponthechoiceofstars.The tion determinations.Positionalastronomywasdrivenbythe tion werepublishedwiththemainresultbeingproofthat themes, alloriginatedbyWHerschel:stellardynamics,du- tions, foundthatsixofthebrighteststarshaddefinitely and starcounting.Morethan100solutionsforthesolarmo- modem basisforstellarpositionsbyaccountingaberra- vation. ThethirdAstronomerRoyal,Bradly,establishedthe second AstronomerRoyal,usingtheresultsofhispredeces- spin-off wasthedeterminationofpropermotions.Halley, erential motionisafunctionofthetotal(andits sor FlamsteedandPtolemyscatalogueofancientobserva- present discussionconcernsstarsinthatstream. dispersion) andforrelativelyslowmoving,mainsequence esis ofnon-preferentialpeculiarstellarmotions.Stromberg changed inthesucceedingcentury.Itwasnotuntilfirst Herschel toobtainavalueforthesolarmotionthatwaslittle tion, nutationandprecessionthewaywasclearedfor shifted theirpositionduringthesome2000yearsofobser- gent pointofthepropermotionsHyadescluster.The of themotionStreamInearlycoincidingwithconver- stars therearetwopreferredstreams(ordrifts)withtheapex decade ofthepresentcenturythatitbecameclear tion. operated bytheAssociationofUniversities forResearchinAstronomy,Inc. (1925) andRaymond&Wilson(1930)foundthatthispref- search forthesolarmotionwasbasedonflawedhypoth- (AURA), undercooperativeagreement withtheNationalScienceFounda- CerroTololoInter-AmericanObservatory, NationalOpticalObservatories, 1615 Astron.J.Ill (4),April1996 In the115yearsfromabout1785tobeginningof © American Astronomical Society • Provided by theNASA Astrophysics Data System 9 members ofthestreamand38%starsbelongtotwosuperclusters.AssumingthatFK5 extension andtheGliesecatalogueofnearbystars,withspacemotionsinratio Two superclustersinstarstreamI(theHyadesstream)areisolatedfromtheobjectsFK5and catalogues arenotbiasedastothepropermotionsize,Gliesecatalogueofnearbystarsmaycontainonly about thesamemeanageandspread,althoughHyadessuperclustermayhaveafewolder(2X10) about halfthestarswithinsome20pcofsun.©1996AmericanAstronomicalSociety. stars andtheNGC1901supercluster,afewmorebluestragglers.Sixpercentofcatalogueare VOT()/VT(NGC 1901)=1.5.Thetwosuperclustershavethesameheavyelementabundanceand XTO 1 Cerro TololoInter-AmericanObservatory,NationalOpticalAstronomyObservatories,Casilla603,LaSerena,Chile 1. INTRODUCTION THE STELLARCONTENTOFSTARSTREAMI Received 1995November19;revisedDecember19 Electronic mail:[email protected] 0004-6256/96/111 (4)/l615/15/S6.00 Olin J.Eggen ABSTRACT 1 though theerrorsaresomethreeorfourtimeslargerthanfor berg 1989)orontrigonometricparallaxsolutionsandal- mainly basedonrecentmeridiancirclepositions(e.g.,Carls- three orfourtimesclosertothesun.Thefundamentalequa- the FK5stars,objectsarethemselves,inmean,some from twocataloguesofaccuratepropermotion,theFK5 cluster members,A,D=6?4,6!5(Eggen1984a;Schwan ter membersare tions oftheconvergentpointmethodselectingsuperclus- All ofthestarsinthreecataloguesthatqualifyasHyades where (v,r)arethecomponentsofpropermotionin proper motionsoftheGliesestarsareinunits0.001arc- of thetotalspacemotion,P.V.=0.1V,thent/v—0.1/ limit, forstreammembership,ofthepeculiarmotionat10% where Xistheradialdistance(pc)fromsun.Ifweseta gent point(A,£>),Xistheanglebetween(A,D)andstar, direction, andperpendiculartotheofconver- (Gliese 1969).ThepropermotionsoftheGliesestarsare (Fricke etal.1991)andfromthecatalogueofnearbystars (Fricke etal.1988)andtheHRstarsinFK5Extension 0.0001 arcsecandthatImagnitudes fortheGliesestarsare with threelimitations,arelistedinTable1.Notethatthe and limitations are(1)sinX>0.5for allstars,(2)Vot>20km/s supercluster membersonthebasisofpropermotionalone, sin XfromEqs.(1)and(2).Also,Eq.(1), substituted fortheVmagnitudes oftheFK5stars.Thethree sec, whereasthosefromtheFK5 cataloguesareinunitsof 1991) willbeadopted.Streammembersselected TOT X = The convergentpointofthepropermotionsHyades P.V. =AT=4.74rD(pc),(2) 7t=4.14v/V sinX,(1) y=4.74iAD(pc)/sin X.(4) Vtot43.5 +0.045X,(3) T0T TOT 3. STREAMI(HYADESSTREAM) © 1996Am.Astron. Soc.1615 1996AJ 111 . 1 615E 1616 © American Astronomical Society • Provided by theNASA Astrophysics Data System FK5 103928 100689 115604 114576 112074 110951 209100 129723 126661 122250 121682 206952 202627 201092 201091 134482 130871 197989 166205 137422 134505 134481 188228 46588 41297 HD 59717 58425 42818 32440 26162 22231 64185 62898 65456 11937 82328 73171 13709 13161 84441 75691 74575 85503 84999 92787 85563 93410 92855 97989 95272 94860 4128 6178 3158 O. J.EGGEN:STARSTREAMI 60/-237 967/800 6799/2946 821/120 2332/324 2286/324 -95/-3S6 -864/-6067 31/4073 232/595 -558/1870 -566/1506 -182/-287 184/63 -56/66 1044/-320 1499/-398 -1306/867 -108/108 -287/-28S -2925/-1527 -9515/-5357 -432/332 -2158/-565 -462/411 -26S7/-667 276S/-54-0.0200.923 -715/-229 -1673/537 -1089/-60 -S34/-94 -4608/1295 -1254/210 -693/43 -326/29 -4071/39 -608/83 -946/-314 -1175/479 -709/256 -981/-675 581/-266 41387/31822 52118/-3041-0.0580.854 4124/-721 -955/485 -2527/1116 -185/204 39409/-25583 3574/3263 724/4330 1174/980 131/546 oroooi 9407/198 829/-2S 2357/16 2317/93 6105/-533 331/30 639/13 397/36 404/-20 337/41 86/8 1073/-32 1253/-76 1544/444 475/14 1948/418 1092/31 196/-3 1611/-53 545/-30 2230/-74 3291/-242 10898/-692 1561/146 153/0 4783/-184 838/48 327/-5 614/10 750/-30 694/-33 995/-63 1757/42 46815/4053 560/44 753/-30 1068/93 1087/88 4S37/-97 2750/258 1268/106 275/47 1266/-92 639/-11 1191/-89 1070/41 -0.0380.855 1335/43 1529/49 1510/-30 oroooi v/r -0.087 -0.030 -0.061 -0.015 -0.093 -0.027 -0.034 -0.061 -0.033 -0.049 -0.064 -0.074 -0.033 -0.054 -0.057 -0.038 -0.040 -0.007 -0.048 -0.016 -0.073 -0.075 -0.040 -0.064 -0.061 -0.086 -0.016 -0.020 -0.079 -0.013 -0.020 0.007 0.040 0.090 0.091 0.020 0.028 0.121 0.098 0.093 0.000 0.028 0.087 0.081 0.016 0.084 0.094 0.032 v/r 0.999 0.998 0.890 0.769 0.890 0.860 0.909 0.999 0.997 0544 0.785 0.992 0.548 0.929 0.948 0.932 0.676 0.776 0.805 0.860 0.751 0.792 0.909 0.772 0.936 0.998 0.980 0.982 0.946 0.975 0.989 0.985 0.959 0.949 0.979 0.965 0.996 0.991 0.902 0.921 0.995 0.736 0.792 0.927 0.998 0.994 0.870 0.911 sinX Table 1.StarsinstreamI. + 125 +4“05 +3.70 +055 +0.78 + 158 + 1.20 +050 +0.95 + 1.06 +3.05 +055 +2.66 +0.30 + 250 + 0.40 + 150 + 1.00 + 1.25 + 1.60 +0.77 +3.25 +0.16 +0.60 0.00 -050 4.15 +2.87 + 1.28 +0.65 -0.25 + 2.61 +0.92 -1.38 -1.10 -3.20 + 1.44 +1.70 +0.17 +3.60 +4.05 +752 +0.46 -3.40 +6.99 +052 + 1.13 +0.77 + 1.00 -1.00 M ■0.20 -1.90 +8.35 -2.00 v I (7.25) (5.75) 4.75 551 5?57 5.60 5.45 5.30 5.40 5.45 556 5.21 5.10 2.04 5.78 3.20 3.02 3.78 5.90 4.70 4.00 3.16 3.46 5.17 555 2.95 3.87 3.78 4.70 5.85 4.11 6.65 6.40 6.15 7.34 5.40 5.40 6.75 6.30 3.44 5.69 6.45 4.68 4.65 4.20 3.87 6.15 4.40 6.02 5.19 3.95 3.00 3.38 2.46 km/sec ObsComp ‘'TOT 105.8 120.3 58.0 50.6 22.2 67.7 395 26.4 61.8 96.8 28.7 22.8 85.2 27.9 75.0 22.6 54.0 28.8 22.0 27.9 22.9 12.1 55.0 75.6 475 +18.2+4.0 45.4 39.0 66.0 17.8 455 38.8 24.6 22.3 24.0 29.9 29.4 35.9 57.9 87.7 31.1 33.0 34.9 +1.0-18.1 83.7 435 99.0 -64.0-51.6 62.9 30.0 20.8 14.8 13.0 17.8 + 34.8 +25.8 + 13.0 +88.1 +56.4 + 125 +24.8 + 10V + 15.2 +205 + 15.3 +28.4 + 15.4 +245 +27.0 + 13.8 + 27V +22V + 34.4 +46.9 -125 + 7V +65 -10.2 -50.0 + 36: -21.0 -25.1 -22.4 -28.3 -145 -35.0 -10.0 +5.0 -40.0 -385 -10.6 +1.0 + 3.8 -6.0 +9.8 + 75 -2.0 -3.9 -8V 0.0 0V -8: + 18.0 + 135 +62.7 + 19.0 + 14.1 +52.8 + 12.7 + 19.7 + 105 +48.7 + 155 + 13.9 + 16.6 +385 +35.8 +40.3 +22.9 + 11.4 + 13.8 +33.1 + 12.9 + 37.9 +8.0 +3.9 +2.0 +0.9 +9.4 -10.2 -17.9 -13.4 -22.6 -345 -14.0 -11.3 -38.6 +7.2 -15 + 2.0 +4.7 +0.8 -3.6 -2.2 -2.4 -7.8 -45 -8.8 -45 -1.4 A0 V A2V A5III F8 III/IV A2III K1III F8 V Kl II-III K9III B9 V Ml III K5III K2III K3III G81II G9III Fl V K1 III B2III F6IV K3III F2IV GO II A5 V A5III F5 III K2III K2III K0 III G9III K0/1 III GOV Am Am Fm F0V B9 V K0 III Al V A3 IV M65 III F4IV-V F3 IV Ap A7V A2II-III K7V K5 V K0 III B9 V F2 V K5 V K0 III G8III Sp.T. 2830 2401 2209 2165 3013 2878 3070 1629 1090 3468 3408 3113 1283 3518 3775 3873 4191 3910 3905 3888 4574 4468 4367 4287 4272 4978 4897 5245 5017 5646 5529 5491 5405 5261 5735 5649 5647 6789 8387 8086 8085 7492 7590 8317 8135 566 652 622 293 188 140 HR Note X X 1616 1996AJ 111 . 1 615E 1617 O.J.EGGEN:STARSTREAMI © American Astronomical Society • Provided by theNASA Astrophysics Data System FK5 Extension 105340 105702 205512 700039 147677 141832 141714 130144 125560 123515 115403 115365 212211 208735 172555 165970 162579 159517 215456 212643 199684 197630 195961 194937 Gliese 146 HD 119B 119A 106 61363 27604 82554 72071 68077 99564 95934 94232 92036 90264 73155 72922 14988 12230 1261/542 55.3AB 55.1AB 55 45 81.2 77 31 26 GL 10.1 18 506/738 361/133 -125/159 -1546/2119 -813/-446 -217/-328 -531/-1285 -237/79 -1492/1375 -637/-3S -39S5/-684 -1086/242 -970/1262 -1099/234 -1575/156 -977/192 565/-T27 430/172 -1403/-827 -764/-626 -834/207 -1919/607 -301/-66 488/-305 -39/-89S -464/2112 -156/-1414 -955/1097 242/-1494 293/430 235/-18 1Q58/-616 445/192 420/149 402/101 2096/-501 1249/982 671/180 669/84 176/-19 1144/-627 See FK5 286/0 298/304 330/215 T27/-446 1542/37 1034/110 (/?001 070001 895/7 385/-1 2671/255 926/45 393/-5 4027/-362 2027/96 202/-3 250/3 1372/-28 636/-56 1388/86 994/-8S 1102/-71 573/55 0.0960.710 462/-29 0.0620.550 985/70 0.0700.716 858/53 0.0620.859 2010/-68 -0.0340.906 307/21 -0.0690.934 519/35 0.0670.997 S97/-52 -0.0580.924 2161/68 0.0320.846 1000/94 921/3 0.0000.867 1620/171 0.1060.687 1123/-28 -0.0250.986 1583/10 235/16 0.0690.797 1420/89 0.0630.981 1452/-81 -0.0560.744 1508/127 0.0840.852 2154/81 0.0390.931 1586/94 0.0590.888 1224/19 0.0150.718 485/4 446/7 414/4 674/20 499/-46 694/23 286/-1 177/-1 -0.0060.866 1304/-31 -0.0240.962 855/-41 394/13 1541/-74 1039/-64 oroooi (/POOl v/t +0.094 -0.003 -0.020 -0.017 -0.012 -0.065 -0.088 -0.090 -0.089 -0.062 -0.048 -0.002 -0.093 0.098 0.048 0.062 0.008 0.047 0.011 0.006 0.030 0.016 0.010 0.999 0.033 0.048 0.033 0.008 w/r sinXMy 0.918 0.980 0.877 0.565 0.811 0.700 0.908 0.958 0.990 0.996 0.974 0.937 0.996 0.996 1.000 1.000 0.983 0.998 0.999 0.998 0.991 0.918 0.899 0.966 0.996 0.995 Table 1.(continued) +2.80 + 1.00 +3.05 -16.3 + 155 + 150 +2.20 + 1.41 + 1.34 +3.00 +0.06 +3.08 +0.17 +2.80 +2.28 + 1.38 + 1.20 +0.21 +2.80 + 1.00 +2.09 + 1.41 +356 +0.64 + 1.10 +0.60 + 1.00 +359 +0.34 -056 +3.94 + 2.43 -0.90 -2.86 -1.35 +4.88 +4.3 +3.47 +559 +4.91 +659 +8.65 +7.64 +4.27 +5.86 +6.43 +853 0.00 -1.45 -0.22 +2.14 M(I) (5.69) 5.25 4.82 5.82 5.72 550 4.85 5.34 5.85 6.07 6.14 4.93 5.94 6.00 5.93 5.70 4.84 5.90 6.42 4.85 454 5.7V 4.76 5.89 5.02 7.60 550 4.84 6.45 6.40 4.80 6.25 5.76 6.01 6.09 6.12 6.64 6.25 456 458 4.98 6.77 6.44 8.18 8.90 7.12 7.97 9.49 8.71 7.62 7.25 km/sec ObsComp 'TOT 128.3 130.4 110.0 59.3 435 40.8 53.0 54.8 965 21.4 205 24.9 375 44.1 24.6 73.9 58.6 -36.0-9.8 17.0 81.8 21.4 28.6 44.7 64.3 18.0 53.2 64.0 63.8 21.7 49.6 58.6 28.7 255 24.7 255 29.7 35.4 12.9 51.9 51.4 52.8 54.9 56.0 64.8 14.7 34.9 22.8 87.0 69.8 26.8 +27.4 + 19.0 +39.8 +20.0 +335 + 10V + 14.9 + 16.9 + 15.8 -26.0 + 35.7 + 115 + 11.0 -45.3 + 195 +75.6 + 15.6 -17.0 -19.1 -22.3 -25.0 -54.8 -23.0 -29.6 -25.1 -30.0 -11.0 -64.6 +4.4 +7.1 -15.0 +0.2 -18.8 +5.7 +6.6 +5.2 +8.0 +2.0 + 35 +2.2 +8.0 +2.4 +4.2 +0.4 -8.0 -9.1 + 17.2 + 18.0 +43.7 + 125 +42.3 +27.0 -34.6 -14.0 -66.8 -34.0 -42.9 -93.2 -37.6 -37.3 -245 -26.9 -17.8 -15.0 +25 +4.1 -30.0 +7.0 +7.2 -13.9 +35 +4.1 +8.6 +6.8 +2.6 + 6.3 +35 + 13.9 + 30.6 -3.9 -7.6 -5.0 -2.0 -8.2 -7.4 +9.3 + 7.0 +4.6 -1.6 -45 -4.1 -7.3 0: A3 V F0V A6 V Kl/2 II FO V K0 III F5IV K3III Ml III B8V F3IV G8III G9III G9IV Kl II/III F4 IH/IV A2 V F3III A5 rv/v K3III B9IV F K0 III K0 III K1 III G35 III M5III A0 V FS V B8/9 V F5III G9III F4 V Sp.T. M2 HI KUH G9III po rv G3IV-V K5 V F6 V K2 V F8 V K7V M4 K3V K7V M3 Ml G5 V G4 V GOV G174-20 G174-19 (Name) G69-10 4089 4309 4240 4162 2939 3795 3408 3393 3355 3200 4617 4416 5370 5296 5010 4629 1365 5893 5889 5512 6899 6656 6552 6103 7012 8255 8043 8031 7933 7859 7820 8527 8378 8658 8542 22496 581 HR Note 703 17051 12058 11112 15633 HD 4128 7788 7693 7570 2025 496 X X 1617 1996AJ 111 . 1 615E 1618 O.J.EGGEN:STARSTREAMI © American Astronomical Society • Provided by theNASA Astrophysics Data System 304 268 226 223.3 Gliese 368.1A 363 356A 320 429.3 377 371 162.1 157.1 431 430.1 380 447.1 397.2 459.3 478 563.2A 545.1 563.2B 567 579.4 579 604 582.1AB 634 609.1 604.1 820 806.1 831 825.1 936.1 848. IB 848.1A 845 844 891 848.1C HD 906 GL FK5 84999 DeltaScutivariable. 46588 Sp.B.,P=60.0d.Trigonometricparallax 0.049 arcsec,photometric=0.045arcsec. 13161 Sp.B.,P=31.4d. 55/-1308 87/568 215/327 T27/-252 -735/-501 -297/337 -198/228 -443/-945 -225/225 -712/-740 -1351/-503 -1090/610 -412/27 -420/226 -580/0 -351/86 -648/84 -107/2 -695/170 -897/-100 -499/-106 -1199/-170 1310/49-0.0400.825 -398/-T2 -830/480 -444/217 -188/-131 -263/-180 -371/-258 487/-431 -370/485 Sec FK5(NGC 404/147 See FK5 See FK5 387/-T8 710/35 234/-135 See FK5 1190/-7Ö 330/50 (/?001 070001 »*«//*» 574/10 449/-14 413/10 301/24 391/15 771/46 477/-9 339/-31 889/23 750/-53 1038/108 1306/-86 1901 supercluster) 580/0 301/9 510/-19 898/89 6S3/-27 716/0 1440/-60 1248/60 492/44 107/5 451/31 404/-21 993/42 340/2 609/31 0.051 205/1 651/-5 430/10 394/29 708/69 306/19 1192/1 333/-16 0:0001 (/P001 »/r -0.071 -0.031 -0.066 -0.092 -0.019 -0.042 -0.041 -0.031 -0.090 -0.052 -0.008 -0.049 0.026 0.080 0.104 0.018 0.039 0.059 0.024 0.048 0.025 0.014 0.047 0.000 0.099 0.042 0.007 0.006 0.070 0.074 0.002 0.023 0.053 0.895 0.097 v/r sinA, 0.634 0.823 0.799 0.552 0.969 0.842 0.968 0.775 0.956 0.889 0.791 0.998 0.896 0.889 0.982 0.966 0.982 0.995 0.997 0.993 0.900 0.852 0.753 0.839 0.767 0.844 0.698 +8.18933 0.768 0.894 +4.98 0.713 +10.45 0.848 0.767 0.938 0.997 Notes toTABLE1. Table 1.(continued) +30.0 + 10.17 +9.15 +8.56 +2.62 +5.00 +9.51 +5.09 +5.40 +6.12 +5.82 +3.40 +6.77 +8.83 +3.50 +9.24 + 7.67 +2.52 +6.73 +7.35 +7.85 +5.73 +5.80 +8.14 +5.52 +4.65 + 1.91 M(I) + 3.83 +5.91 +4.30 +835 +8.05 +8.60 +639 +6.94 Mv +6.83 (9.23) 10.17 (7.79) 10.09 4.90 5.94 5.99 5.93 1036 11.27 9.94 6.70 831 4.60 5.08 7.12 9.04 7.68 5.88 8.43 7.15 9.05 959 8.90 8.06 5.30 9.78 6.06 830 7.03 7.13 6.13 9.07 9.42 8.47 6.36 8.24 830 I km/sec ObsComp Vtot PSp.T. 1523 178.2 1513 116.0 41.1 57.8 56.9 51.8 57.8 92.2 40.0 363 98.1 29.4 73.3 35.1 40.4 34.9 803 37.2 24.3 63.4 49.0 783 313 55.2 58.6 373 723 99.0 62.9 77.0 34.4 23.2 62.9 62.8 -38.0-28.0 83.7 65.1 38.11 + 14.6 + 15.1 +273 +94.0 +20.7 +48.1 +37.1 + 19.6 -21.0 + 35.6 -26.0 -22.0 -10.6: + 13 -22.1 -31.0 +4.4 -23.6 -64.0 -20.2 +7V -17.6 -24.1 -15.8 +3.1 +53 -6.1 -78: -1.1 -21.2 -34.2 +263 +25.2 +25.0 +59.0 +82.3 +70.6 -313 -163 -85.6 +333 +32.7 + 10.2 +48.2 + 14.1 -55.2 -35.4 -24.7 -39.4 -62.2 + 153 -26.2 + 10.4 -613 -12.3 -40.4 -22.6 +7.2 +7.6 +3.8 +5.2 +4.6 +4.9 -3.0 M4 M5 G8 V K2V M5 M3 G8IV G3V K5 V Kl V G6IV K7V M4 F6IV Ml F6 V F0V M M M2 V K3/4 V M K7V K2 V M K5 V G5 V G4 V M3 G5 IV M5 G5 V M2 V G4IV-V KO IV M M M M -25.10553 -13.11010 +23.2359 +29.2279 201091/2 -26.16501 51.13182 +25.2874 -29.8019 G195-36 G222-11 G126-49 (Name) G87-26 L396-7 L38-15 125595 134987 G130-9 102590 131511 205457 136466 144284 143120 142709 205905 197989 209100 40105 82885 70642 26490 85488 85228 74576 HD 88230 G6-42 91324 10004 G26-7 HR Note X X X X X X 1618 1996AJ 111 . 1 615E 1619 O.J.EGGEN:STARSTREAMI nearly allnormalstars.Thecalibrationsadoptedhereare AF B typeandAO tems availablehavebeencalibratedfortheluminosityof for theGliesestars,and(3)membersassignedtoHyades FK (classIandII) GK (classIII) GK(MS) and IC1901superclustersonthebasisofallinformationin M giants Sec. 3and4areomitted. The (RJ)photometry ismainlymyown.The luminosities The Strömgrenphotometryis from Hauck&Mermilliod (1980) andtheGenevaphotometry isfromRufener(1988). Photometric parametersforthevariousphotometricsys- © American Astronomical Society • Provided by theNASA Astrophysics Data System FK5 Extension 55.1/55.3 356A 268 Gliese 368.1A 563.2AB 567 582.1 848.1 170951 Sp.B.,P=38.3d.AV0.43mag.Themagnitudeoftheprimaryislisted. 218670 Sp.B.,P=4096d. 114576 Equalcomponents.Thelistedmagnitudeaccountsfortheduplicity. 115604 AOCVn,DeltaScutivariable. 129723 BPOct,DeltaScutivariable. 115365/463 305arcsecseparation. 195961 DeltaScutivariable. Star 90264 Double-linedspectroscopicbinary.Heweak? 27604 AV=3mag,0.6arcsec. 95934 A4881weak. RI Geneva, RI Strömgren, Geneva Strömgren, Geneva Strömgren Strömgren Strömgren, DDO, Both areclosedoubles;55.1hasP=81.3y,a1.08arcsecand55.3isKappa(l)Tue Double-lined spectroscopicbinary,P=10.4d.Assumedequalcomponents. Kappa(2) Tue,separatedby5arcsec. Close 13magcompanion. Close 12magcompanion. Separated by27arcsec. A-BC, 408arcsec:B-C,11arcsec. SpJB., P=125.4d. Equal components,1arcsec. System Eggen (1995a) Eggen (1977) Eggen (1994b) Eggen (1993b,1994a) Eggen (1986,1995b) Eggen (1992a) Reference Table 1.(continued) the clearareasofFig.1foreachcatalogues.Multiple p= VtotcosX,andtheobservedvalue. Table 1alsocontainsthepredictedradialvelocity, Table 1andthevaluesofVarethenderivedfromEq.(4). obtained fromthecalibrationsleadtomodulilistedin dom. slightly excessivevaluesofVtot^55-60,thedistribution stars arecountedasoneobject.Althoughtheremaybe tion. Theidentification ofthissuperclusterwith itsepony- that inadditiontotheHyades supercluster,theHyades shown bytheclearregionsofFig.1canbeconsideredran- Stream containsanothersupercluster withlowerspacemo- c XOT A histogramofthevaluesVtotinTable1isshownby During thecourseofthisinvestigation itbecameapparent 2. NGC1901SUPERCLUSTER 1619 1996AJ 111 . 1 615E 8 9 Fig. 1.Distributionoftotalspacevelocitiesforstreamstars.Themembers areas. of theNGC1901andHyadessuperclustersarerepresentedbyhatched bers areadded.Thepropermotionsoftheseaddedstars At theendoftableseveraladditionalsuperclustermem- the starsinthreecataloguesthatapparentlyconstituteit. mous clusterwillbediscussedbelowbutTable2contains not includedintheFK5anditsextensions(seeSchwanetal mainly fromtheCarlsberg(e.g.,1989)meridiancirclecata- Af(Clus)-M(Photo), is+0.07±0.15magfortheFK5 logues orthecatalogueofimprovedFK4supplementstars km/s fortheFK5cataloguesand—0.4±1.7 the clusterluminositycomparedwithphotometricvalue, The photometricvaluesofMinTable2comefromthe 1620 O.J.EGGEN:STARSTREAMI mean differencesbetweentheradialvelocitypredictedby calibrations listedinSec.2.Themeandifferencesbetween nosities andcolorsoftheNGC1901superclustermembers, ter isshowninFig.2whereisochronesfor8X10and catalogues and+0.05±0.14magfortheadditionalstars.The Gliese 669A8790 the additionalstarsofTable2haveIandR-1values in theAppendix. to havemorebluestragglers.TwomembersoftheNGC known tobebinarieswithAVbetween0.2and2.0mag.The with membersoftheHyadescluster(Schwan1991)not are alsorepresentedinFig.3byclosedcirclesandcompared additional stars.The(M,B—V)diagramforthesuperclus- supercluster parametersandtheobservedvalueis+0.1±2.0 Gliese 669B9.94 and arerepresented byclosedcirclesinFig.7. similarities aregreatalthoughthenewsuperclusterappears 1993). Thetotalspacemotionofthesuperclusteris (Maeder &Meynet1991)arealsorepresented.Thelumi- 1901 superclusterrequirespecialattentionandarediscussed 1.25 X10yr,frommodelswithconvectiveovershoot +38.2445 9.51 v -6.15 9.18 v v The superclusterreddwarfsintheGliesecatalogueand Vt= 28.2+0.045X(pc).(5) TO Star I © American Astronomical Society • Provided by theNASA Astrophysics Data System + 10.251.41 +9721 17195 +7.48 0.71 +7.34 0.72, Mj R-I 1 78 The nearexactagreementwiththephotometricmodulusof be hadbyexaminationofthephotographregionpub- bers. EvidenceofDreyer’sremarkabletalentinhistaskcan motion butthecomputedradialvelocityagreeswellwith tions forfivemembersareavailablegiving from whichhederivedE(fc—y)=0.027[E(l?-V)=0.035 rediscovered in1960,appearingtheliteratureasBokNo. lished bySanduleak&Philip(1968).Theclusterisprojected the editor,asasmall,roundclusterwithatleastsevenmem- a superclustermember; mag] andatruemodulusof8.09mag.Accuratepropermo- against theLMCata=5?3,£=—68?5andwasserendipity percluster parallaxandarerepresentedinFig.2bycrosses. ferentially withrespecttothebackgroundLMCstars,agrees mean ofp(obs)=+8±2km/sobtainedbyFehrenbach&Du- 8.09 magmustbeaccidentalinviewofthesizeproper listed inTable3togetherwiththeluminositiesfromsu- well withtheadoptedvalue.Fifteenclustermembersare of allthemembersderived,byMurrayetai(1969),dif- flot (1972)from118observationsof13stars.Propermotions represented byhatchedareas.Thereasonfortherelatively logues areaddedtothehistogramsofFig.1wherethey cluster (e.g.,Eggen1983). lar tothatofanotherverypoorcluster,theUManucleus The luminositydistributionofclustermembersisverysimi- (/¿,^<5) =(0.002,0.013)±(0.001,0.001)arcsec,leadingto,as the well-knownbiasagainstsmallpropermotionsin discussed inthenextsectionbutanobviousexplanationis parison, themembersofNGC1901superclusterin catalogue ofnearbystars. because oftheproximity clustertotheconvergent M=4.56(Æ-/) +3.95.OnlyfourHyadesclusterstarsfrom reproduces theHyadesclustermainsequence, the (Mj,R—I)planeofFig.5wherecontinuousline mag arerepresentedinFig.4byclosedcirclesand,forcom- small numberofmembersintheGliesecataloguewillbe point ofthepropermotions.The geometriccenterofthe the FK5andtwofrom ExtensionareinTable4 in theGliesecataloguearerepresentedbyclosedcircles Tables 2and3,withtheexceptionoftworeddestgiants, catalogues arelistedinTable4.ThestarswithM<+6 Hyades isonly2h(30°)fromthe convergentpointsoabout are representedbyopencircles.Thesuperclusterreddwarfs 1. Phillip(1973)publishedStrömgrenandH/3photometry nated fromconsideration here.TheHyadessupercluster is one-half theclustermembershave sin\<0.5andareelimi- a 7 v r X= —53.2pcp(Comp)=+6.3km/s. P.V. =2.9km/ssinX0.970 Object number1901intheNGCisdescribedbyDreyer, The superclustermembersintheFK5andGliesecata- r= 0.002arcsecV=25.8km/s F=0.013 Modulus=8.04mag The HyadessuperclustermembersintheFK5andGliese TOT 4. HYADESSUPERCLUSTER 1620 LO H

Table 2. The NGC 1901 supercluster. 1621 O.J.EGGEN:STARSTREAMI © American Astronomical Society • Provided by theNASA Astrophysics Data System » >i r>< > c O :S jC Û. 4-* O o j't? E' • oj ^rjrointoo in«- p'OinN-oh- co>p •cKm«—•>4’in>o N- inomN-oin'4-'4-oto O »2«- ' -r»i«— « >CM — > in too«-eoM)CM00Kop >4-in>Oin^>iinroin>t'^tocM CM «— O o CM o mm> inO'inOifOfO^iOb-iTj^g^ N- inCM in N-«- in fl0O'0'>0t0KT-CM'4’>*CMO'O no O'to ^ nís.sftoro'OCMeo^ooto m sn t? • + 1 sf in^tocm>to to intON-OON.-Mh-stO^O' oo O'ininooro&»>to«->4-cm«o«-'JN-O'' So «-o»> «- cmto^mN> O »-<>1 » >o in cmooo CM CM in >tcm N* «-o»cmmo^ + + ♦ g «—«—«—CM > ) o< • C>K.CMI CM «- cmtor SSSSSSSS 3St25£88ïîü<8 in «—oo< s> >o• M ^2«>~ « ^ cm in«-I o O'toini oooooooo + ♦ N> <4-IiCM>4 ♦ +i rSSíSSSíS ! ^5ooS$ ' CMr-toI>S "O CM*-toO «- o>oS • iICM^ I CM g ^ • ooinM> in N-oocm«4-^^ i|i äsSIIStESälä i >tKo ¡S8R NÍtOtOOC)CMh2«^OoÓcM>í'0 '0«-CM00^«-^«-inOCMK «2roo+cMS^too>cMin>o '0>0to>(>oinin ^>oto cM^oootoK.CMOO'Oooo OQOopinKtocMin'4’>Oin ^SkÍo^Soo^^iSS^Scm sr^m^tincMtomincM^-^ '0««í-NON-'Oin>í-'Oinininin ininininin_inin in m «-oi«-«-♦>0«—cm>o o^tepooocMinc^^to^tN- lOCMtOCMCMCMCMCMCMCMCMCM or2rôt^fldoôaÔKinr2h2in NtinooO'OoO'4-N-toin«-«- K u>op 0'«-'OCMN- m 355 odoooooooooo _ ,CM*-O''ON>O00 777 's. 's»i + I«-1 ++y T+7+ >o«-to«-in^^«-tooo* >'Oinocor^CMin'ON-toco mtoincMOO«-o«-srin >tooeo«-in«-ooo'Ooeo in >íot • ‘*-—^%t + III + 58 §ls; RS in i in oocm S¿^ 's. MrCM I o>too«-O00 is O' ini RRJ cm m 3^ «4 tsSt-O'< gg~R. 'S. 'S»' v T—CD — JKiK)-5 «- to ss I 'S» » CM fR Ri to I Sn CM 9 S RSR ^ g O (9 O CM ÍRÍ fs 0N-00 gig: .°: á ootoin d 400>* «— »4tO O O''O«- CM 's'S cm «-ooo in toop cm N-oo«- in M)o to ’S'S00 O *-00 M> O'«”O in ofs>4 (QRR8 's I>4• 'S toI's i +*-«- • + + • pK-«- CM tO > m 'Oto îïf to '4 ■S3 + rS 1621 LO

Table 2. (continued) 1622 O.J.EGGEN:STARSTREAMI © American Astronomical Society • § X & ^ o 9 £■ o I o OO^O'O^'OKÍ 00 K) CNJ«>(M00Oooin co to§•> =>>>> hi j-cminoornKisa 'Om'Oinh*->i->o*->oo s-om«-K)S-CMO m ^ min rJ>t'0^«^>t^cM ro ooK-«“Nj-mc>mo o< •-K cm^min+ Ni-coooo»-in>00 in o CMO»ON-«-m ^ooooooo o 00 OM>CM>4- «««-'i i >foocM^cMinrwcM >t ini•->> oo 'O*—iNiroin inm^CMinN>CM in^OQrnoo>tro N-mo N.^^QKI'OnJ-CM • íÍÍS' • t 'J-•-'v.im + O K'OinCMN" •N n*m> i 8;•§! ;s I— < *■» ■M o s o j Provided bythe NASA Astrophysics Data System ^ OD0D ro *- go. CL •* «» ro 5 odd < C/>(/> «0 *o 2t5'I 2 7:8-3 S Ï. O 5**“ *?.* : 3 g. 5 !o Û. — <^ 00*- <0 ÛS « o -< û.o.or K. «>CM00 Mr OO»CM >Q CM u C II> ..8 3 in 1 ? *•» M> 0 oT « « ■ .a o£ (M C-L> ■s. i 4-> I •- <0 Í.J *ï « O i £ î-î CD o • s 1622 1996AJ 111 . 1 615E Fig. 2.ColorluminosityarrayformembersoftheNGC1901supercluster. 1623 O.J.EGGEN:STARSTREAMI there appearstobeverylittledifferenceinagebetweenit discussed indetailelsewhere(e.g.,Eggen1993a,1995a)and planes astheHyadesclustermemberssoheavyelement indicesfortheNGC1901superclustermembers, and theNGC1901supercluster.Theavailable[mjra percluster memberscomprise1.7%oftheFK5catalogues There areabout1500starsintheFK5,around1000HR FK5+Ext 3324 hatched areasinthehistogramsofFig.1; in theStrömgrenandGenevaphotometricsystem,show in theFK5Extensionand1000Gliesestars,soHyadessu- Gliese 242. abundance isnear[Fe/H]=+0.1dexforboth. same distributioninthe—and(Æ2—VT,ra) the twosuperclusters.Fromstatisticslistedabovethere and 2.4%oftheGliesestars.Sixpercentcatalogued stars areinthestreamand38%ofbelongto proper motionbiasintheFK5catalogues,Gliesecata- cluster givemaximumpropermotionof0.25and0.125arc- are about15missingGliesecataloguemembersoftheNGC about 22parsecsandtheparametersofNGC1901super- logue containsonlyaboutone-halfthestarswithin22par- [Eq. (4)].Theimplicationisthat,sincethereprobablyno sec formembersatthatdistanceandwithsin\=1.00.5 secs ofthesunandmissingobjectswillbemainly 2 1901 supercluster.Thiscatalogueislimitedtostarswithin Fig. 3.Comparisonofthecolor-luminosity arraysformembersoftheNGCFig.4.Comparisoncolorluminosity arraysformembersoftheNGC 2 1901 superclusterand theHyadescluster. 1901 andHyades superclusters. The Hyadessuperclustermembersarerepresentedby © American Astronomical Society • Provided by theNASA Astrophysics Data System Hyades NGC1901 40%, werecontainedintheGliesecatalogue.Itshouldbe than 0.5arcsec,wereisolatedandonlynineteen,orabout of theHyadessupercluster,mainlywithpropermotionlarger perclusters havethesameconvergentpoint,differencein pre-main-sequence objectsandthereforemoredistant. noted thatthedistancesofthesehighpropermotionstars small motion.Previously,(Eggen1993a)49singlemembers membership isrecognizedonthebasisofonlytwoparam- Hyades, andthereforeevenclosertothesun,othersmaybe were obtainedfromtheHyadesmainsequenceand,although in afewcasesthiscanleadtodifficulty.Anexampleisthe eters, theradialvelocity,andphotometricluminosity, be measured.Twopossibilitiesare noted thatthesecondaryspectrum,althoughdetected,cannot some maybeoflowerheavyelementabundancethanthe NGC 19013.54+15.7. Hyades 4748+24.2km/s short period(0.65d)eclipsingbinarySAnt(HR3798).The My =+1.80magasamemberoftheHyadessuperclusteror My =+2.15and+1.90mag,respectively.Themaximum spectral linesarerotationalbroadenedandPopper(1956) magnitude is6.28mag,or,ifthesecondaryignored, The GenevaandStrömgrenphotometricindicesleadto My Because thepropermotionsofmembersbothsu- 20 12 11 10 17 15 14 13 No. +2 +3 4 3 +4 +i 7 6 8 +5 9 1 o (B-V) 269271 269310 269301 269315 269312 269338 269324 269319 35140 35094 35026 35183 35293 35462 HD Table 3.MembersofNGC1901. % 0.2 0.4 Modulus p c 10.18 11.26 10.27 10.37 10.79 12.44 10.31 11.46 10.13 8775 9.62 8.97 9.13 9.05 9.77 +2.14 + 0771 +2.03 + 1.09 +2.03 +2.75 +4.40 + 1.01 + 1.58 +0.93 +3.42 +2.09 +3.22 + 1.73 +2.27 M v 0.155 0.165 0.185 07225 (B-V) 0.105 0.205 0.165 0.22 0.295 0.59 0.425 0.18 0.415 0.125 0.20 0 AS A7 V Sp.T. A5 V A3 V A2III A5 A7 Am A7 AS GO F8 F0 Aim 1623 LO

Table 4. 1624 O.J.EGGEN:STARSTREAMI Hyades supercluster American Astronomical Society •Provided bythe NASA Astrophysics Data System ^ 1 > CO •58 ^ =• O (0 . 8 «O 4= Q. •M I o o , fON.N.a"OK.in&sON-«-in>ooomoo«-o>o< £••••••••••••• •••••••■ mco0'0rsj>t'4''0o0'0«-o -^->tooo(\JíOíO>4-'í)rvj>í-in'OC>0'«--o^^rupQino v-ininm^ooOo Eo«-incoEonjni<\imE*-OCQ f 8fciS888!85î!2223a8!P2!? .^Sts5:8888fcS8= K(MCMin^inr^roO'mcMNi«->ooo«-^eoomO'0 >>ino0'00'0 ■■in>ooo ® «^'>tmm^O'00CMr-«r->tCM»P-O^CMmN-in-^' oommcMoooo«*”«—m«“ ^. ooooooo«^ooooodoo«r^p«^oooo So in^o•«t CM st>tmindcm ttm'00'«-CM«-mKincM0'© >o0''00'in'00''0>* si'4'4‘si-*i^i«i’slsisi«4’si'4’ St^si^si^si^ist cm most«o©ro'ooostcom«- dddddddddddd«-^ ddddddddd 0'0'^0''0inininN.ininrs.o to^O'O'N.N.KwO' 2'^‘?‘t“^îP”l0 Qin«ph-stMin« «inininN.mO''0«-strs-o omM)p'O«-min _ inm m K©•-mK.^c0's*>t'O©m«-O' «—mrvjin«-«—«—«—N.in«-in«- cmcm«—fs.©«-m«-0' stommst«-cM«-»-0'«-©'0 stooinstinO'«-min stCMinstinOOOOmoOr^CMOCM ©0Q'O'O«-«-CM»O' «-o«-st©Qst'p's^>smmst ©«-^*s^'Omst*s* NÍ j«—•«CM^OOJOO^U*»» o cmmin«—O'O* «-oocM'r-0'incMcov*in^oöQ msj*>o. stO'PnWst«—cMowm«—st«— cmCMO'«—mo£«—mgi M 'S* ^QN.«—’s* xxxxxxxx oo pcmm(M«-m«-n>o^ sfin«-o«r-0'CMO'0>tN-K- o»roN-mcoN-Kl^co cm in^i o t>tcMin(Mmm^>>tminmin • +•+♦♦♦1 > njoooroni>><> rÔKN!flô«^nj«3>ô N-'Omomeonjin «—«—•(Mm» i• «- cmstm N- «—’s*eo•^s^m >t inmst«-N- cm O'in»-S- 'O ^ >s^>I s»inKcMCM«-'Ost I inCM'OcmM>o^ X «“(MCMf ^ «-stO'•»*- f-CM 'S'QS*p*»0Qr—>0 !Ír:2t-§2¡ ‘RRSttlS! 1 |R inro'Osfoooo m'4-N.N»omO' >>>>>>>> stdcMmstcMstm SCM mrs.>0N.eo cSSS^SomSp opof3m in dddornddst cMN-winN-mstm •-«-«N.O'mcMm ♦ m+wni + mmm^^ dddddddd O' K-in< p> m«oI st ©mN-c ©©©CMinstCMO' m st©«P-«-co O ©•»1I00 jo '0©in'p«“ststm O' _'OOCQCM «— «“T“ ^oop«-cognj'0st«-0 m *-s*.s^^. ♦ +V Ss.t-s^s^-^n**^^ s*. •s*,s*,o • 'tnjm«—« ^ cmK-»om«st»- OmCMCM>i-«-«- 7* *' i O'eo «—•—«— O -ssssa I» >O»N»N- 11 O w £00N>

Table 4. (continued) 1625 O.J.EGGEN:STARSTREAMI © American Astronomical Society • Provided by theNASA Astrophysics Data System -I _8 O (0 CL 4-» I o O ïii OC CO — > o Ü X.O 9 =• w a. o o > o sf O (MCQ zoo RSS &S2?; o >o co il! dN-cor^r2inddddddr^ddd m >tocmO'««-ro•-Kro *- omO'^egn*cmcoinN>N.«>m> m msssssäiisssiH rod ro co in in i S! Ssfro a>cmstN-vin co in«r-u-«V. in r^ inromc/>ro>4>4’inc/>«- *-«-roin'0<5ro>i>t '4h-'gcoin^ocMro ^ ^ ,, • cdN. K oN.ro > ^ o cmôroco »o «-MCM r* r-~ i Sro co -in o c*Am *“ ÍM«-CM «r- >j-Chr^- 3 C3 •- + «- inCO>0 «-■ inCO'O r- + K- o-in + CM «r-O + ♦ O roCM<«0 + m *-oh» ro + >4- >t *- CM«- >4- OCMro + «- S I>4- - sfro >0 T“ cm ro o d CM «-«“ n4- m-oocmin PLSSoSolC s + in • roh. o coMrtt)in'ON. oo inro• cm Ko «O •in-st o > cm ro ro h- SSS! > in co«—'OCO«-*r-KO''4-co»nro o cmsregK.mooN>K in >omO'inN-CM^-cOin'O'O'ON- + ♦«-+ in w + ro O; sf j§ îî *■" »OOCMrOj4-CMfOCMCM^>p m^-ro^cMCM^-^N-coo ^«-«-CM'x'XCMr-m'^CM > » rocm«-in&^ N-inCMfOCM-OOr-'O'«* CM sfON- ro cm♦•««- oorooin>oinrocMin 2S2ÏÏ2SSSÏ a‘ •rôoi«>tcô>o > in inC0*“«“'OO'fOC0'OCM CM^Oh-^O'OfMCMO' fs»'O?C0^>ÍNÍ>íKÍ>t inN-CM*-C0in'O'O'ON- roconimO'4in>oinN> ooo«-«-ooooo ♦ +.»i 0'^tom>tF>*-'0CMC0 dcM'OOsrO'ro^cM'O + +•“♦♦♦ N- CM>4 ocMrorocMcommo^ m >0 »-T-*—mo^cm i CMr^r-Iw~ - •0 in m cg^h-omcMoeor^ I +•>t >o «-T-r-roincm - 'cmin^— w «f W + O >tCM< in ON-CM( » CO^O' I N-•-N" UJ s o d « c. o 1 «4- ü 2 d 1 4-* I 85^ co C CD c. 8. 0 s ♦-» O 5 ? co L. Ü — X So ro «- CM á oi;fc CD 8. L. C. in « o cm n4-N- o 4-» $ fc. O CA CD a> s ai

Hyades cluster. 1625 LO 1626 O.J.EGGEN:STARSTREAMI © American Astronomical Society • Provided by theNASA Astrophysics Data System Notes to TABLE 4. Continued. § 1626 1996AJ 111 . 1 615E 1627 O.J.EGGEN:STARSTREAMI not affectingthecolors.InanearlyorbitalsolutionJoy the laterpossibilityisprobablyexcludedifcompanion Popper (1956)estimatesitto+15km/sandthislatervalue information onthelightdistributioninsystemandobvi- agrees withthatpredictedfrommembershipintheNGC (1926) obtainedasystemicvelocityof—5km/swhereas NGC 190126.4 tion. ously moredataareneededtosettlethemembershipques- Hyades 40.4 +2.74 magasamemberoftheNGC1901superclusterand the NGC1901supercluster.Thedomainsofyoungdisk and theHyadeshavenearlyexactly1.5timesvelocityof in Fig.6wherethepositionsoftwosuperclustersarealso labeled. Thestreammotionisindicatedbythepaththrough 1901 supercluster.Theshalloweclipsesgivelittleaccurate the solarandsuperclusterpositions; (YD) andolddisk(OD)starsinthe(t/,V)planeareshown 1.5X NGC190139.6 The colorluminosityarraysinFig.4indicateverylittledif- and, becausetheWmotionsareverysmall,V~2.12V. Fig. 6.Thedomainsoftheyoungdisk (YD)andolddisk(OD)starsinthe indicated bylineconnecting superclusterandsolarmotions. TOT U, Vplane.Thetwosuperclustersarealso labeledandthepathofstream Fig. 5.ReddwarfsoftheHyadessuperclusterin(M,R-I)plane. 7 The spacemotions,atthesun,oftwosuperclustersare £/= 2.53V(6) © American Astronomical Society • Provided by theNASA Astrophysics Data System U 5. DISCUSSION -15.6 -2.243.2 -10.4 -1.528.2 -16.0 -3.043.5, V Wt TO km/s 7 9 bers oftheNGC1901superclusterin(M¡,R-I)plane. Fig. 7.ThevariationsofDHLeo,andthepositionsreddwarfmem- ference inthemeanageandspreadoftwosuperclus- ters, althoughtheearlierdiscussionofHyades(Eggen If weadopt(t/,V)=(-8.1,13.2)km/sasthesolarmotion with respecttothelocalstandardofrest, NGC 190118.3+2.80.10 Hyades 31.3-2.80.12, motion of(i/,V)=(-33.5,13.2)wouldproduceidentical bears totheHyades; respect tothecepheidsbearssamerelationPleiades consistent withthedynamicsofcepheidvariables(Caldwell orbits forthetwosuperclusterswithe—0.02(Contopolous& and thegalacticperiodsdifferbylessthan10yr.Asolar Strömgren 1965).Thevaluesof(£/,V)=(-8.1,13.2)are 1995a) suggeststhatitmaycontainstarsasold2X10yr. & Coulson1987).Itisinterestingthatthesolarmotionwith Cepheids supercluster (Eggen1992b)astheNGC1901 The pathofthePleiadesstreamisalsoshowninFig.6. Pleiades, Hyades,andNGC1901superclustersallhavea heavy elementabundanceindicatedby[Fe/H]—+0.1dex 0 nates thePleiadesmotion,soresultingvaluesoftotal about 45km/s/kpcand,becauseoftheisoperiodicity ades andNGC1901motionswhereastheVvelocitydomi- separate stellarorbits,arotationmeasuredbydV/dX=—(B (Eggen &Iben1988)andshowanoverallexpansionof 0 space motion(e.g.,Eggen1992b)are 1.5X Cepheids 0 —A) =26km/s/kpc.TheUvelocitypredominatesintheHy- Fig. 8.ThevariationsofDHLeointhe (M,B-V)plane. v U' V'e 12.2 11.5 U 8.1 (km/s) -20.8 -19.8 -13.2 V -10.5 -10.5 -7.0 W At thesun. km/s 1627 1996AJ 111 . 1 615E best visualobservationsofAB,andalltheavailableinterferometricABAa(kindlyprovidedby AB -0.058-0.021 C —0.058—0.024arcsec ADS 9775fjuaaA modem meridiancircleresults(Carlsberg1989)give Resolution inAstronomy)observersfoundtheAcomponenttobeaclosebinaryrapidmotion.TheCis51 change, whichisprobablywhyithasnotbeenmonitoredveryclosely.In1983theCHARA(CenterforHighAngular mean cepheidmotioninthePleiadesStream(sometimes How muchofacoincidenceistheapparentpresence with anuncertaintyof±0"001(¡ma)and±O'.'003(julS)forABtheyobviouslyformaphysicalsystem.Aselectionthe arcsec distantandsharesthepropermotion.ADS9775AB=BD-27.10550C=-27.10549.BothobjectsareGCstars dence oftheasymmetryinstellarmotionsonplace heid, aremembersofthePleiadessupercluster(e.g.,Eggen Pleiades Streaminthefigure(Eggen1994b,Figure4,£/= giant andsupergiantsoftypeGKliealongthepath called streamO)ofFig.8?About20%thenearestbright Hartkopf 1995)areasfollows: £896.49 £991.40 The visualobserversagreethattheABcomponentsareofnearequalmagnitudeandHartkopf(1995)statesAa 1628 O.J.EGGEN:STARSTREAMI ADS 9775C magnitude, orV=7.30magandAaareequalatV=8.05mag.ThreeobservationsofAaBC(UBV)madein1967, close enoughinbrightnesstoplacethequadrantdoubt.ForpresentpurposeswewillassumeAaandBareequal from theabovetabulation.Although AaBisatriplesystem The firstinvolvesthephotometric propertiesandismanifest Hyades MainSequence ADS 9775AaB Hyades MainSequence with similarHyadesclusterstars(Schwan1991): combined colorandlightplaces thestarsonmainse- with magnitudesnear7.30mag(B) and8.05(Aa),the and Geneva(Rufener1988)Strömgren(Hauck&Mermilliod 1980)photometrygivethefollowingresultscompared 1961). Thisquestionispartofanother,involvingthedepen- — 0.6V)andtwoorthreecepheidvariables,includingSCep- quence definedbyHyadessingle stars.Thesuperclusterpar- 1898.83 1892.41 allax alsoplaces thesingleCcomponenton Hyadesmain 1983.90 1980.23 1965.53 1959.55 1941.06 1927.00 1924.38 1990.30 1987.40 = Vtot 26.1+0.025X(pc)Pleiades There aretwoenigmasconcerningthisquadruplesystem. t © American Astronomical Society • Provided by theNASA Astrophysics Data System 42.5+0.045Z Hyades. 28.2+0.045X NGC1901 170 171 172 171 171 172 167 167 166 163 161 170 154° e 0T31 +0?05 B-V U-B 0.79 +0.45 0.79 +0.43 0.31 +0.09 0.576 0.569 0.565 0.555 0:50 0.52 0.70 0.56 0.45 0.41 0.65 0.46 0.39 AB P Worley Aitken Burnham Chara van denBos van denBos van denBos van denBos Fox, Voute Chara Chara Chara +2744 +07243 +5.39. +5.33 +2.59 0.247 M [mj v by Burnham,100yearsago,thepairhasnotshownmuch These questionswillbediscussedindetailelsewhere.Paul the PleiadesStream,containsstarsthathaveconsiderably centuries afterHerscheltheyarestillanuisance. lower metalabundancethanthePleiades(andHyades). Schechter referstoUandVas“nuisance”parameters;two Stream II(,UMa),whichisnearlyorthogonaltothat stellar originandmetallicity.Forexample,themotionof 0.43 magforB(M=+3.4mag) and0.55magforA combined tomatchtheobserved colorof0.31magandde- tion isthatthe AB componentiseithersingle orthestars a(M=+4.09 mag).Theseabsolute magnitudescannotbe sumed above,theexpectedcolors formainsequencestarsare sequence. IftheindividualcomponentsofAaBareasas- spite thevisualandinterferometric observations,thesugges- 0 v y (1) HD140722(HR5856)isADS9775AB.Discovered 1984.38 1983.43 1990.27 t 07688 27748 0.626 2.751 I>i] ß 230 109 71° 6 APPENDIX 0:219 0.207 0.203 Aa P 17093 —07478 1.030 -0.472 d m 2 Chara Chara Chara 1628 1996AJ 111 . 1 615E have amagnitudedifferenceof2magormore.Theonly notable departureinthematchbetweenADS9775AaBand the Hyadesmainsequenceinabovetabulationis ultra-violet (U—B,[cj,andd)deficiencyforADS9775. lack thereof.TheobservationsofABcanbeinterpretedas 1629 O.J.EGGEN:STARSTREAMI pair. ThefewobservationsofAaindicateveryrapidmotion with aseparationoflittlelessthanonehalfthatAa-B. This situationsuggeststhattherapidangularchangeinA-a showing nomotionin100years,buttheobservedangular is theoriginofrelativelylargescatterinobservations separations areunusuallydiscordantforarelativelywide of separationinAa-B,becausetheincipientresolutionAa tions ofAa-B,0.5arcsec,andA-a,0.21astheappar- ent radiioftherespectiveorbitsandmassequivalentto the luminosities,Æ=1.4,Aa1.3thenfromKepler’s shifts thelightcenterofsystem.Ifweadoptsepara- nearly correct.However,thesystemofAa-Bshouldhave law P(Aa-B)—85yrandP(A-a)~30yr.Theminimum change inA-aisabout257yrsothepredictedperiod completed anorbitalperiodduringthetimeithasbeenunder observation. DH Leo The radialvelocityofthe 3 Hyades 3 Hyades Aslan, Z.,Dorman,F.,Akalin,A.,&Ozdemia,T.1992,A&A,257,580 0 Caldwell, J.,&Coulson,I.1987,AJ,93,1090 Barden, S.1984,AJ,89,683 Carlsberg MeridianCatalogue1989,LaPalmaNo.4 Eggen, O.J.1961,R.Obs.Bull.No.1 Contopolous, G.,&Strömgren,B.1965,TablesofPlainGalacticOrbits, Eggen, O.J.1978,IVBSNo.1426 Eggen, O.J.1977,PASP,89,187 Eggen, O.J.1984a,AJ,89,1350 Eggen, O.J.1983,AJ,88,642 Eggen, O.J.1986,AJ,92,910 Eggen, O.J.1984b,AJ,89,1358 Eggen, O.J.1993b,AJ,106.1845 Eggen, O.J.1993a,AJ,106,80 Eggen, O.J.1992b,AJ,104,2141 Eggen, O.J.1992a,AJ,104,275 Eggen, O.J.1994b,AJ,107,2184 Eggen, O.J.1994a,AJ,107,594 Eggen, O.J.1995b,AJ,109,1327 Eggen, O.J.1995a,AJ,110,823 Eggen, O.J.,&Iben,Jr.,I.1988,AJ,96,635 Institute forSpaceStudies,NASA The secondenigmaispresentedbytheorbitalmotion,or © American Astronomical Society • Provided by theNASA Astrophysics Data System +5753 0.967 +6.25 1.185 +6.25 0.855 My V X third, fixedcomponent,+17km/s,hasbeenadoptedasthesystemicvelocity. = 3164Â 4015 Â44765395À 07405 0.369-0.195 0.890 0.388-0.178 0.577 0.443-0.162 B Vi x2 REFERENCES member oftheHyadessupercluster(Eggen1984b),dis- covery byBarden(1984)thatthesystemistriplewitha The KOVandK5components(Strassmeir&Fekle1990) cally activebutthefixed,thirdcomponent(K5V)isnot.The of thespectroscopicbinary(P=l.ld)arebothchromospheri- systemic velocitynear+17km/seliminatesthatpossibility. variation inMandR-I(Eggen1984b)isshownbysmall each oftheK5Vcomponentscontributesabout10%.The M=4.56(R-I) +3.95(Eggen1993b).Thetotalvariationin line representstheHyadesmainsequence, KO Vstarcontributes80%ofthelightatX6430Â,whereas 1978) oftheRSCVntype.Althoughconsideredaprobable dots intheplaneofFig.7wherecontinuous the (M,B-V)planeisshowninFig.8whereHyades Leo inVandB-ViswellcorrelatedwithV-4.54(B-V) main sequenceisfromSchwan(1991).ThevariationofDH Hyades mainsequencestarsofthesamecolorand ment ofDHLeoinFig.8canbeseenacomparisonwith luminosity intheGenevaphotometricsystem(Rufener 7 I + 3.87(cf.Aslanetal.1992).Thereasonforthedisplace- v 1988): Fehrenback, Ch.,&Duflot,M.1972,Observatory,92,645 Fricke, W.,etal1988,Veroff.Astron.Rechen-Inst.Heidelberg,No.32 Fricke, W.,etal.1991,Veroff.Astron.Rechen-Inst.Heidelberg,No.33 Griffin, R.E,Gunn,J.,Zimmerman,B.,&E.1985,AJ,90,609 Gliese, W.1969,Veroff.Astron.Rechen-Inst.Heidelberg,No.22 Hartkopf, W.1995(privatecommunication) Maeder, A.,&Meynet,G.1991,A&AS,99,451 Joy, A.1926,ApJ,64,287 Hauck, B.,&Mermilliod,M.1980,A&AS,40,1 Murray, A.,Dickens,R.,&Walker,W.1969,Observatory,69,104 Phillip, A.G.D.1973,ApJ,180,421 Rufener, F.1988,CatalogueofStarsintheGenevaPhotometricSystem, Raymond, H.,&Wilson,R.1930,AJ,40,121 Popper, D.1956,ApJ,124,208 Schwan, H.1991,A&A,243,286 Sanduleak, N.,&Philip,A.G.D.1968,AJ,73,566 Schwan, H.,Bastian,U.,Bien,R.,Jährling,B.,Jahreiz,&Roser,S. Strassmeir, K.,&Fekle,F.1990,A&A,230,389 Stromberg, G.1925,ApJ,61,363 Geneva Obs. 1993, Veroff.Astron.Rechen-Inst.Heidelberg,No.34 (2) DHLeo(HD86590)isavariable,spottedstar(Eggen 5807 À 07000 07564K2Y 0.000 0.566K2V 0.000 0.606K3V. G BVSp.T. 2l 1629