19 66ApJ. . .143 . .192Z hms/ 8 ence orabsenceofcompactcoresgalaxieswhichinappearancearestellarandcomparableluminosity Long- andshort-exposurephotographsofNGC4874itsneighborsillustratetherespectivepres- chosen rangefromF«=764km/secto11470km/sec;theirindicativeabsolutephotographicmagni- to theisolatedmediumgalaxies.Representativesofasubclasscompactgalaxiesarediscussedwhose regions whichexistedinthediagramofstructuralcharacteristicsgalaxiesversusspectraltypesasit spectra arecontinuous,withavarietyofallowedandforbiddenemissionlinesH,Hen,Cm,iv, was establishedforabout550ofthegalaxiesinvestigatedbyHumason,Mayall,andSandage. vestigated sofarwiththe200-inchtelescope,anditwasfoundthattheybegintopopulateallempty spectrum arediscussed.Aboutonehundredcompactgalaxiesandpartsofhavebeenin- compact galaxies,onewithacontinuousfeaturelessspectrumandtheotherbroad-bandedemission arc; andtheindicativediametersoftheircompactcores,from68to1400pc.Ifdoublesystemat R.A. 930anddeck+55°27(1950)canbeassumedtostationary,itsindicativemassis5D7> tudes, fromM——11.8to—20.9;theirsurfacebrightness in the present series of papers (Zwicky 1964a). Actually, as our knowledge of compact galaxies grows, it will become necessary to characterize the individual objects through the use of ever more significant parameters. Among these, the average surface bright- ness Apparent Photographic Magnitudes mp and Surface Brightness 0- per Square Second of Arc for a Select Group of Galaxies and Compact Parts of Galaxies Epoch 1950 Object mp R.A. Decl. Galaxy 64 in Cl 0124-0133. 0h- 27“2 -01° 30' + 14.9 87". +24.6 Galaxy 32 in Cl 0124-0133. 0 21.4 -01 53 + 15.3 11.7 +20.4 Compact dwarf in Virgo. .. 12 28.0 +12 46 +14.5 12 + 19.6 Compact (Zi) galaxy 1 20.6 +34 19 + 13.9 6.7 + 17.8 Disk of compact (Z2) galaxy 1 01.2 +29 52 + 17.6 2.4 + 19.2 Nucleus of M31 0 40.0 +41 00 + 12.8 2.5 +14.5 3C 273 12 26.5 + 2 20 + 12.0 < 0.25 <+10.2* Sun -26.2 32' -10.2 * Assuming that the radius of 3C 273 is r < 0T25. II. ON SOME GALAXIES WITH COMPACT PARTS IN THE COMA CLUSTER For our understanding of the physico-chemical evolution of the Universe, knowledge of the amount and the distribution of mass is indispensable. The assumption that the mass of clusters of galaxies, for instance, can be derived from the integrated luminosity of these clusters has led to results which are in flagrant contradiction with the values of the masses deduced from the internal velocity dispersion (Zwicky 1933). This disagree- ment would disappear if the existence among the member galaxies of a cluster of a suffi- cient number of objects could be demonstrated, whose mass-luminosity ratios are much larger than those of ordinary galaxies. The conjecture that compact galaxies and com- pact parts of galaxies may play a role in this connection is indicated by the comparison of the images of various types of cluster galaxies as shown in Figure 1, a and b. Atten- tion is called in particular to the appearance on the long- and short-exposure photographs of the four galaxies listed in Table 2. It is seen that the brightest among the four galaxies, NGC 4874, with diminishing exposure time, fades away the fastest since it has no bright, compact central disk. Of the other three systems, Nos. 1-3, the outlying “suburban” populations disappear on shortening the exposures, but starlike images of their central disks remain long after the whole image of NGC 4874 has disappeared. Plates of the Coma Cluster obtained © American Astronomical Society • Provided by the NASA Astrophysics Data System 194 F. ZWICKY with the 48-inch Schmidt telescope with different exposure times show that about 10 per cent of the galaxies in the range 13.0 < mv < 15.7 possess compact central parts of stellar appearance. For purposes of a rudimentary morphological classification of the distribution of surface brightness in galaxies, and particularly in those of the E and So types, it is proposed to investigate the relative luminosities of the nuclei, of the central disks, and of the suburban formations of galaxies (spiral arms, secondary belts, halos, etc.). A similar proposal was made by V. A. Ambartsumian in one of his reports to the I.A.U. assembly at Hamburg in August, 1964. In Paper I of this series (Zwicky 1964a) data on three compact galaxies were pre- sented whose spectra show them to be essentially agglomerations of G-, F-, and A-type stars with or without low-excitation lines, such as X 3727.2 of [On] appearing in emis- sion. In the following we discuss compact galaxies whose spectra show many emission lines superposed on featureless continua in which, at the dispersion used, no absorption lines are in evidence. TABLE 2 Galaxies near the Center of the Coma Cluster Epoch (1950) Vs* No. NGC nip (km/sec) R.A. Decl. 4871 12h57m05s +28° 13 .'7 15.1 4873 12 57 08 +28 15.1 15.4 4872 12 57 09 +28 13.0 15.3 +6910 4874 12 57 11 +28 13.8 13.7 +7171 * Vs = heliocentric symbolic velocity of recession (Humason, Mayall, and Sandage 1956). III. THE COMPACT GALAXY AT R.A. 16h22m06s, DECL. +41°12' (l95(fi This galaxy, a photograph of which is reproduced in Figure 2, appears as a bright disk with a sharp outline. Around this disk an extremely faint halo may be seen. On medi- um-exposure photographs taken in moderate seeing with the 200-inch telescope, the sys- tem, however, appears entirely stellar, the apparent diameter being smaller than 2", while the width of the halo is less than 0''5. The apparent photographic magnitude of the central disk is mp = 15.4. Its photographic surface brightness therefore is © American Astronomical Society • Provided by the NASA Astrophysics Data System 19 66ApJ. . .143 . .192Z © American Astronomical Society •Provided bytheNASA Astrophysics DataSystem CVJ # LU * Fig. 1.—(a) Photograph with the 200// telescope of NGC 4871, R.A. 12h57m05s; decl. +28013.'7 (1950); and surrounding galaxies near the center of the Coma Cluster on emulsion 103a-O, exposure time 15 min. Scale as indicated, (b) The same field as in (a) on emulsion Ila-O, exposure time 1 min. 19 66ApJ. . .143 . .192Z © American Astronomical Society •Provided bytheNASA Astrophysics DataSystem LU Fig. 2.—200-inch telescope photograph of compact galaxy at R.A. 16h22m06s; decl. +41°12/ (epoch 1950) on emulsion Ila-O, exposure time 15 min. Seeing 2. Scale as indicated. 19 66ApJ. . .143 . .192Z X ¿'¿919. 9'Z\9Z- (H)SOi7£t7- 8 (H)¿*IOÍ7- © American Astronomical Society •Provided bytheNASA Astrophysics DataSystem ZSI09- ¿‘888£- h m s 0 Fig. 3.—Spectrum of the compact galaxy at R.A. 16 22 06 ;odecl. +41 12' (1950) obtained with the prime-focus spectrograph of the 200-inch telescope on emulsion IIa-0 at a dispersion of 400 A/mm. Many emission lines but no absorption lines are visible super- posed on a blue continuum of relatively high intensity. 19 66ApJ. . .143 . .192Z © American Astronomical Society •Provided bytheNASA Astrophysics DataSystem # Lü Fig. 4.—Interconnected double galaxy at R.A. 14h39m12s; decl. -b53°44/ (1950), obtained with the 200-inch telescope on emulsion Ila-O, exposure 15 min. Seeing 2. The compact core of Galaxy 1 is discussed in the text. Scale as indicated. 19 66ApJ. . .143 . .192Z 6 6 dicative diameterofthe core islessthan1100pc,andtheabsoluteindicative photo- magnitude oftheluminous coreism—14.4anditsphotographicsurface brightnessis thus cr<15.6.Sincewe shall findthattheindicativedistanceis115X10 pc,thein- A faintspiralarmisseenemanatingfromGalaxy 2towardthenorth. 2" indiameterandafainthalo,about7".5diameter. Theapparentphotographic by afaintbridgenotvisibleinthereproductionbut indicatedinthesketchofFigure5. km/sec. AssumingthatVisentirelyduetotheuniversalredshiftandnosignificant part ofitmustbeascribedtoanEinsteingravitational redshift,weobtainfortheindica- emission lines,is(V)=10250km/sec,withastandarddeviationofAV±300 tive distanceofthisgalaxythevalue102.5X 10 pc. p 8 sS gaseous halowhichenvelopsthecoreofgalaxy. rent methodsofanalysis(GreensteinandSchmidt1964)toestimatethemass of seeingandguiding,relativetothecontinuum,itmightbepossiblebyusecur- calibration oftheintensitytheselinesonspectraobtainedunderbestconditions of thishalothatemitsvisibleemissionlinesisthustheorder100pc.Uponexact distance ofaboutO''25fromthelimbcoregalaxy.Theindicativethickness intense; noabsorptionlinesarediscernible.Likethecoreitissharplybounded,andonly the strongemissionlinesprotrudefromittobothsides(eastandwest)apossible of theheavieratoms. and showaslighttendency,ontheaverage,tobebroaderforhydrogenthanthose lines whicharenotblendedorobscuredbynight-skyoftheorder10-30 lines atX3886.0and3829.6couldnotsofarbeidentified.Thehalf-widthÔXofthe We areinterestedhereprimarilyinGalaxy1,which hasahardluminouscorelessthan A photographofthissystemisshowninFigure4. Galaxies 1and2areinterconnected © American Astronomical Society •Provided bytheNASA Astrophysics DataSystem The averagesymbolic(heliocentric)velocityofrecession,asderivedfromfourteen The continuousspectrumwhichemanatesfromtheluminouscoreofgalaxyisvery He. nr HÔ. N. Ni. 2 Line Emission LinesMeasuredintheSpectrumofCompactGalaxy IV. acompactgalaxyintheinterconnecteddouble system H H [Ne v] [Ne v] H Element H [O II] He II H [Ne III] [S II] [O III] [O III] [O III] ? ? hms AT R.A.162206,Decl.+41°12'(1950) h AT R.A.U39™2,DECL.+53°44'(1950) (3705.0) COMPACT GALAXIES (3760.0) 3425.9 3345.8 3868.8 3727.3 3970.1 4071.2 4101.7 3888.2 4340.5 4363.2 4686.8 4861.3 4959.9 5006.8 Xo TABLE 3 3462.7 3543.6 3829.6 3853.2 3886.0 3999.2 4021.7 4098.7 4208.5 4247.0 4488.8 4510.0 4839.5 5030.5 5136.9 5183.5 Intensity Relative vw m m m m m m w w w m w s s s s 24 20 30 29 10 14 20 22 25 18 ÔX (km/sec) 10480 10310 10140 10010 10300 10120 10630 10240 10000 10440 10710 10590 9720 9770 V s 195 1966ApJ. . .143 . .192Z © American Astronomical Society •Providedby theNASAAstrophysics Data System +,J rl ^ s.a oo 35 05 $ ^ u rB LO ^ + a ■Ö ^3 LO - o ^ o- ^ P¿ I OO [_| M-í tí !z: ^ "a cj ^ tí OH ^ be tí O . o c/o ^ .a §.§ tí ^ LO Ph ^ O g o .S o; ’fi 21 O X S'! s.l tí :3 c Mtí S o3 O N E 10" I 1 » Fig. 5.—Sketch of the interconnected double galaxy reproduced in Fig. 4 TABLE 4 Emission Lines Measured in the Spectrum of the Compact Galaxy AT R.A. 14h39m12s, Decl. +53°te' (1950) Relative V3 Line Element Xo In tensity d\ (km/sec) Ni. [O III] 5006.8 5199.7 s 21 11560 N2. [O III] 4959.9 5149.5 m 16 11470 H/3 H 4861.3 5047.7 m 15 11510 He II 4686.8 4867.7 w 11580 C III, C iv (4657.0) 4837.0 vw Broad [O III] 4363.2 4527.1 s 16 11270 H 4340.5 4503.6 s 21 11260 HÔ. H 4101.7 4256.0 m 18 11930 [S ll] 4071.2 4208.5 m 23 11160 ? (4027) 4179.7 w He. H 3970.1 4121.7 s 11460 nr H 3888.2 4039.3 vw 11660 [Ne III] 3868.8 4015.2 s 18 11340 ? (3762.0) 3901.6 w [Oil] 3727.3 3866.8 vs 23 11230 [Ne v] 3425.9 3554.4 ms 17 11260 [Ne v] 3345.8 3477.9 w 11840 ? (3096.0) 3215.7 vw © American Astronomical Society • Provided by the NASA Astrophysics Data System 19 66ApJ. . .143 . .192Z x (H)S0l7£t>- (ÜH)Z'\99t> 8 ( H)¿-|OH7- © American Astronomical Society Q'Ufrt’- rsioQ ¿'8882 - Z 'Z81£ 9'£ 192 . ,'(;/.l,15,*«3 ■■' »i■* Provided bytheNASA Astrophysics DataSystem «MMMMl' mm ; U.. fNMN> • a•„maláfáa'ifc.v^-^ 111 A.l*: ^ J4•HÄiV■**.''* Fig. 6.—Spectrum with the 200-inch prime-focus spectrograph at a dispersion of 400 Â/mm of Galaxy 1 shown in the photograph and the sketch of Figs. 4 and 5. Slit of the spectrograph was oriented north-south. Spectrum shows many emission lines superposed on a continuum of moderate strength, but no absorption lines are recognizable. 19 66ApJ. . .143 . .192Z © American Astronomical Society Provided bytheNASA Astrophysics DataSystem LU Fig. 7.—Double compact galaxy at R.A. 9h30n30s; decl. +55°27/ (1950); 200-inch telescope plate on emulsion Ila-O, exposure 15 min. Seeing 3. Scale as indicated. 19 66ApJ. . .143 . .192Z 6 moderate intensityforGalaxy 1and,relativetotheemissionlines,veryweak inGalaxy plane normaltothelineofsightisthus211pc.Two veryfaintflareslie24"northwest parallel lanes.Theindicativeabsoluteseparation ofthetwogalaxiesasprojectedona of sometheoutlyingfaintformations. of thesystemtwointerconnectedgalaxiesdiscussed. of Galaxy1,eachabout2"indiameterandwith a distanceof4"betweenthem.Itcan it thesmallestextragalacticsystemknownsofar. The surfacebrightnessofthecoreis<7^18.6per squaresecondofarc.Theindicative from theluminosityGalaxy1isamediumsystem.Theindicativeabsolutediametersof SE. alongtheinterconnecting bridge,isreproducedinFigure9.Thecontinuum isof only beconjecturedthattheyandafewadditional exceedinglyfaintpatchesformpart are interconnectedbyanarrow,luminous“bridge” whichisflankedbytwofainter absolute characteristicsareM{2)=—11.8,2 = 147pc,2Ri—66thusmaking grated indicativeabsolutemagnitudeM(V)=—13.8,whichmeansthatjudgingonly plane normaltothelineofsight. The apparentcharacteristicsofthesystemareasfollows: the galaxyandofitscoreare2R=246pcRi66pc. shall findthattheindicativedistanceofGalaxy1is7.6X10pc,weobtainforinte- comparable withthevaluesfoundforgalaxiesdiscussedin§§IIIandIV.Sincewe emanating fromGalaxy2tothenorthis23"or,indicative,12700pcasprojectedona tion, normaltothelineofsight,28000pc.Thelengthveryfaintspiralarm separation ofthetwogalaxiesis51",whichcorrespondstoanindicativeabsolutesepara- same distanceasGalaxy1,itsindicativeabsolutemagnitudeisM=—19.0.The integrated apparentphotographicmagnitudeism=16.3and,assumingittobeatthe + 15.6;andthesurfacebrightnessofcoreo-=16.6persquaresecondarc,whichis p P a 11470 km/sec,withastandarddeviationAV=±224km/sec. p p 8 hms/ © American Astronomical Society •Provided bytheNASA Astrophysics DataSystem The spectrumofthetwo galaxies,withtheslitofspectrographoriented NW.to Fig. 8.—-SketchofthedoublegalaxyatR.A.930;deck+55°27(1950),showingcharacter Galaxy 2.—Diameterofthecore2=1"8;fulldiameter 2r=4";m(2)+17.6. Galaxy 7.—Diameterofthebrightcore2^=1"8;fulldiameterr6"7;m{\) A photographofthissystemisshowninFigure7,andasketch8. The bridgeandtheflares.—Thecentersoftwo galaxiesareseparatedby5"6and The meanvalueofVobtainedfromfourteenemissionlinesinTable4is(V)— ap Galaxy 2hasnocompactpartandreadablespectrumasyetbeenobtained.Its ap s V. THEDOUBLESYSTEMOECOMPACTGALAXIESAT hms R.A. 930,DECL.+55°27'(1950) E COMPACT GALAXIES197 N I 1 10" 4861 5015.7 4471.5 4340.5{Hî 3613.6 y 3187.7 f'A: 4^ 1 v î ^ ’* v > t. j T » //, / \ * Provided by the NASA Astrophysics Data System v v, * ; vtf* î.t* ‘ «s. h m s / Fig. 3.—Spectrum of the compact galaxy at R.A. 16 22 06 ;odecl. +41°12 (1950) obtained with the prime-focus spectrograph of the 200-inch telescope on emulsion IIa-0 at a dispersion of 400 A/mm. Many emission lines but no absorption lines are visible super- © American Astronomical Society posed on a blue continuum of relatively high intensity. O^i CM O^i 1 o tr : 5. ^ ^ • ^' ■’ ' ' ' iv '•• ’■' •• '" ' ' ■' ■ 'i ' ■' c; o» r MMtMnwi>M«MM«nM. - ',«m q o os : 3Í8T.7 3 o o 3 n & * $ÿXtï 2 ' £ 3 ^3 mmmm mmm y2 tr4 crq C/2 a> cr^P ^ ^3* P ft) op^ ° cq ^ p ^ 2 P-i ftn P*9 8 N • ^QrqJlí O Oi-(- CÍ. ^ P P 5*^1? ua»1 tóp o ^ O O ^ 2.^ ^ 2 3 p 4101.7 (H « P a p^ pn'2 ^ CP S3 P" 3* ^ s ™ p 3 WtW&êMï%‘îMm-‘3Ù «H ?§ 4340.5 (H y) ^^ 2.9 oct> o 9 ° 447 L 5 ¡^ £], v ^ ^ \ ^>v> ,y5‘; i" * ^ |l|^>tl > "iP« í'^V'K^j^r i >t ] o hL XP" 2.2- C/5U3 ^O o" p 3 4861.3 (H^g) 5015.7 © American Astronomical Society Provided by the NASA Astrophysics Data System 198 F. ZWICKY 2. In contradistinction to the spectra of the galaxies discussed in §§ III and IV, the emission lines of [Ne v] and [S n] are missing in the spectra of both galaxies, the bridge, and the outlying halos. All other emission lines are seen throughout the whole formation. Attention is called to the fact that X 3727 in the spectrum of Galaxy 2 is more intense than X 3727 for the much brighter and more compact Galaxy 1. The wavelengths, X, of lines measured for this galaxy are listed in Table 5. The strongest lines in the spectrum of Galaxy 1 in order of decreasing intensity are H/3, Ni, Hy, X 3727, N2, etc. All lines preserve the same relative intensity in the spectrum of Galaxy 2 except X 3727 which appears stronger than Hy. From Table 5 we obtain for Galaxy 1 an average (F/) = 778 km/sec with a standard deviation of ±49 km/sec. The correction due to the relative velocity of the Earth and the Sun for the date of observation being —14.1 km/sec, the heliocentric symbolic veloc- ity of recession is V8 = 764 km/sec. TABLE 5 Measured Wavelengths (x) of Emission Lines in the Spectrum of the Brighter Component of the Double Galaxy at R.A. 9h30m30s, Decl. +55°27/ (1950) Vs' Line Element Xo Intensity (km/sec)* Ni. [0 III] 5006.8 5020.5 S 820 N2. [O III] 4959.9 4973.4 m 817 Hß. H 4861.3 4874.5 vs 814 He II 4686.8 4702.5 vw 768 [O III] 4363.2 4375.2 w 826 H7. H 4340.5 4351.3 vs 746 Hô. H 4101.7 4113.1 m 833 He. H 3970.1 3979.6 m 718 nr. H 3888.2 3898.0 m 741 [Ne III] 3868.8 3879.6 w 740 [O II] 3727.3 3136.5 s 741 * Vs' = c(\ — Xo)/X. The spectral lines of Galaxy 2 with respect to those of Galaxy 1 are displaced toward longer wavelength by amounts which correspond to an average difference in V8 of 150 km/sec, with a standard deviation of ±60 km/sec. Taking AVS = 150 km/sec and assuming that the two galaxies form an interconnected physical system, the indicative total mass of the system is9K > 1.43 X 1042 gm = 7.2 X 108 5DÎO. Since the indica- 7 tive absolute photographic luminosity of the system is about Sp = 5.3 X 10 %po, its indicative mass luminosity ratio is 9Î = (9¡)í/!^o)/(£p/£po) > 13.6, if the system ac- tually is a physically permanent double galaxy. On the other hand, if the two galaxies are flying apart, 9K and 9î will be smaller than indicated in the preceding passage. VI. THE COMPACT BLUE SYSTEM AT R.A. IFOS^S, DECL. +28°57' (1950) This system is located 0'5 south of NGC 3561 (Zwicky 1956). V. A. Ambartsumian in 1957 kindly called my attention to the fact that upon comparison of the blue and red prints of the Palomar Sky Survey this object (the Ambartsumian knot) appeared to be excessively blue. Two long-exposure spectra with the prime-focus spectrograph of the 200-inch telescope that I obtained in January, 1958, showed indeed a very weak, fea- tureless continuum and an abnormally strong X3727 emission line (Zwicky 1958). As to its spectral features, the object may be considered as a limiting case of the compact systems which were discussed in the preceding sections. Its symbolic velocity of reces- © American Astronomical Society • Provided by the NASA Astrophysics Data System 19 66ApJ. . .143 . .192Z x l’QQQÍ- (H)9'0^£t^- Z 81£ 9£I9£ ¿*SIOS- © American Astronomical Society •Provided bytheNASA Astrophysics DataSystem •M I MMil .«•< * ■ ■ nlMill mm w M 73 2 1 - ow^JS Æ 3S>,o -5 ^séÖ •»■ ua— exposure 15 min. Seeing 2. Scale as indicated. COMPACT GALAXIES 199 6 sion is Vs = 8900 km/sec and its indicative distance therefore is 89 X 10 pc. With mp — 18.8, its indicative absolute photographic magnitude becomes Mv = — Í5.9 (Zwicky and Humason 1961). Its dimensions are 3''9 X 3''2 and its average indicative absolute diameter is about 1400 pc. The Ambartsumian knot is therefore a medium galaxy and its linear dimensions are about ten times larger than those of the two dwarf galaxies dis- cussed in the previous section. The spectral analysis of the region between the Ambart- sumian knot and NGC 3561 further revealed the presence of two blue objects of the 21st photographic magnitude which appear stellar even when photographed with the 200-inch telescope. In the spectra of these two objects only the bright line X 3727 could be re- corded so far. The redshift of this line being about the same as that for the Ambartsumian knot, it follows that Mp ^ —13.7 for these objects, or about the same as the Mp for component 1 of the double galaxy described in § V. Fiq. 11.—Direct microphotometer tracing of the spectrum of the compact galaxy at R.A. 17h27I?l; decl. -fSiPlS' (1950) obtained with the prime-focus spectrograph of the 200-inch telescope on emulsion IIa-0 and dispersion of 400 Â/mm. Neither any absorption nor any emission lines can be definitely identified within the intense blue continuum. Attention should be called to the fact that on triple-image UVB plates, taken in that order with the 48-inch Schmidt, only the ultraviolet image is visible. The procedure followed was to use the 103a-D plates and the standard filter combinations and exposure times (40 min, 4 min, 8 min) adopted for the extended blue-star surveys (Haro and Luyten 1962). If, however, the object had a somewhat larger redshift, the U image would be considerably weakened and the I? image intensified. For objects with relatively much light concentrated in isolated emission lines or bands, the ratios (U — B)/(B — V) may thus be quite different, although the spectra are identical but Doppler-shifted by varying amounts. VII. COMPACT SYSTEMS WITH FEATURELESS OR BROAD EMISSION-BAND SPECTRA A. I have investigated systems whose spectra in the region from 3000  to 6700  appear featureless and continuous. Figure 10 shows the one at R.A. 17h27“l and decl. o / +50 15 (1950.0). Its apparent photographic magnitude is mp = 16.4 and its diameter is probably less than 1", so that its image can barely be distinguished from those of equally bright stars on plates obtained with the 200-inch telescope. Since the tracings of the spectrum on blue and panchromatic emulsion (Figs. 11 and 12) do not reveal any identifiable features, nothing can at present be said about the distance and the absolute © American Astronomical Society • Provided by the NASA Astrophysics Data System crq o p to p"P rfw ^cr O)P Pg oO 3187.7 S as “ 3 s-21 '< -a g, O g P IÜ£rf wsV) si§f^ O CD O P ^ - i-< p ! ; J ^ ii i^g .5Î {**•} Vr.:‘ iv'S ; »< tr w’ ^ ^ w co ^CD o|—K SH&-"-ro a. P.T^ O crq ^ CD , O P r H+ ^02: :\>h " \ *■ * ^ ' v* p íT o - P >ocT &Í1L s r< crq P P i‘» . « % % « %^ - ,% ^ crq P ^ fi':'v'.\::>W.;:-' cr tí p <-.,' 1 ..‘.L- ; ■ tP> >^ P p ^ r ^ fe ^ s P ^ ^ooyO^o c S: ai ^ O B' o ^ ^Jp P c 2^ cr pT S'-- 3 ^ 2. >j P- p \ P" P ^ R, Cl ^ fl Crq K> g- 2 410 l.7(H a ) ° ^ ^ P p ”, B O P.'' <-h4 O Pp © American Astronomical Society Provided by the NASA Astrophysics Data System 200 F. ZWICKY Vol. 143 geometrical and physical characteristics of the object. Interconnected multiple galaxies will have to be found, some of whose physical members are objects similar to the one in Figure 10, to enable us to elucidate their intrinsic character. B. Among the systems in the field of the medium compact cluster of galaxies Cl 0124- 0133 around NGC 541 (Zwicky, Karpowicz, and Kowal 1965), Galaxy 84, at R.A. 1 o OIMQ ^, deck --01 18' (1950), has the following characteristics: diameter 18"; mv = + 15.1; and average photographic surface brightness Fig. 12.—Direct microphotometer tracing of the spectrum of the compact galaxy at R.A. ITW1?!; decl. +50T5' (1950) obtained with the prime-focus spectrograph of the 200-inch telescope on emulsion 103a-F with a dispersion of 400 Â/mm. All wavelength numbers indicated refer to the positions of the respective spectral lines in the comparison spectrum. No absorption or emission lines are identifiable either in the very weak continuum between 5000  and 6700 Â, or in the intense blue continuum which duplicates that shown in the tracing of Fig. 11. Fig. 13.—Direct microphotometer tracing of the spectrum of the compact galaxy at R.A. lh19™5; decl. —1°18/ (1950) obtained with the prime-focus spectrograph of the 200-inch telescope on emulsion IIa-0 and a dispersion of 400 Â/mm. No absorption or emission lines are definitely identifiable as super- posed on the intense blue continuum. It seems, however, that if the various features are either absorption or emission bands their widths are great, perhaps of the order of 100 Â. © American Astronomical Society • Provided by the NASA Astrophysics Data System 19 66ApJ. . .143 . .192Z © American Astronomical Society Provided bytheNASA Astrophysics DataSystem exposure 15 min. Seeing 2. Scale as indicated. 19 66ApJ. . .143 . .192Z 7 8 12 o inequality shouldbeset at 10SWo. lie intherange7X10 üDîo
19 66Apj. . .143 . .192Z COMPACT GALAXIES and COMPACT PARTS
