I have obtained accurate coordinates and basic IDs for the first 2400 stars in the Dearborn red stars catalogue (file II/68 in the Strasbourg system). This covers the southernmost zone (-5 to +13 Dec) up to 8h RA, thus including high- and low-latitude regions. The goal was to get a better idea of the quality and the systematic errors in the Dearborn types. It is clear from historical usage that the Dearborn types are not well regarded and have been thought to be systematically late compared to good-quality spectral classifications. Is this really the case when compared to modern data?
I took the machine-readable file as a base, and used VizieR to recover the stars in Tycho-2 and TASS (special cases worked over individually), then successively the GSC, IRAS/MSX, HD/BD/SD, and the GCVS v4.1 for basic identifications. Using VizieR to fix a file in VizieR flirts scarily with recursion (please, not in these clothes!).
Although GSC, IRAS, and HD/BD names are complete so that the file is reasonably self-contained, I have included further IDs usually only if these are not known by SIMBAD. Thus, for instance, I do not mention that DO 69 = BY Psc since this is already among the aliases in SIMBAD for BD+11 36. All carbon stars were indicated as being such or not.
Recovering all these stars with their 3'-5' positional errors, while tedious, yielded a large number of IDs and corrections for SIMBAD, and allows one to unambiguously make a visible-light identification for hundreds of 'anonymous' IRAS and MSX sources with a red star having a reasonable spectral type, not to mention BD and HD stars missing from SIMBAD. I found a lot of interesting overlooked stars here. Numerous bits and pieces have been corrected in SIMBAD already by Gerard Jasniewicz.
I was a little surprised to find that the Dearborn magnitudes are in fact systematically quite close to standard V, _not_ brighter, as one might expect from the use of plates sensitive redward of the V passband. I think this results from the old photo-visual scale being fainter than V for red stars, such that the slightly brighter Dearborn 'orange' magnitudes are not far from standard V. This comparison was easy to see using TASS MkIII (Strasbourg file II/230) and corrected Tycho-2 V magnitudes. I would like to mention in this regard that the TASS photometry was often indispensable in correctly identifying the Dearborn stars due to the sometimes erroneous B-V colors in Tycho-2 for the fainter stars. I used it much more often than it is cited in the notes. (Thanks Michael.)
The 2400-star sample file and notes---alas, a mere 5 percent of the complete catalogue, but with much value added---is copied out to the Lowell ftp area:
I have modified Brian's data file slightly, translating the RA and Dec from HH:MM:SS to decimal degrees. You can download my modified versions below.
Michael Richmond, June 14, 2002
Now to the point of all this:
Among the first 2400 entries are about 160 HD stars that appear in vol. 5 of Nancy Houk's HD reclassification survey. Below I show a list of these stars with the Dearborn and Houk MK types added. Houk's types and quality estimates are given in the last two columns. There are a few likely or certain errors in her types.
I have arranged the list in order of increasing Houk type within each Dearborn type bin. Since there are only a few bins, it is easy to see by inspection roughly what is going on. From this sample, it appears that the Dearborn types are indeed too late on average by between 1 and 2 MK subtype steps, and that the scatter is about +/-1.5 subtypes. Remember that the Dearborn classifiers would have regarded only types K0, K2, K5, M0 to be full subtypes among the K stars. A rough Dearborn/MK correspondence is as follows:
DO MK mean rms K5 K3 K2.6 +/- 1.5 M0 K3/5 K3.7 +/- 1.8 M1 M0 M0.3 +/- 2.0 M2 M1 M0.4 +/- 1.3 M3 M1/2 M1.0 +/- 1.9 M4 M2/3 M2.5 +/- 1.5 M5 M3/4 M3.7 +/- 0.8 M6 M3/4? M7 M6 ?
The second column shows mode values while the last column shows straight arithmetic mean figures. The last two steps have only a few matching stars, but it appears that these Dearborn types are not commonly late-M stars. The scatter and the systematic errors are such that one can say that for a given Dearborn type, the true type is most likely to be between that type and two steps earlier (e.g. an M0 star is probably between MK type K3 and M0).
Yes, this comparison includes only brighter stars, but I noticed nothing, particularly in the TASS V-I colors for fainter stars, to suggest there was a problem among the more numerous fainter ones.
The systematic offset seems to result from two causes: the text accompanying the catalogue indicates they included early-K stars in the K5 bin, and indeed few of the stars are as late as K5, but mostly between K2 and K4 by Houk's reckoning. More importantly, the TiO bands in the red region appear at an earlier type than in the traditional blue classification region, and this seems to have offset the Dearborn scale to later types.
In summary, the Dearborn types seem satisfactory given the modest systematic offset. I note that the Case classifications for M stars are also offset about -1 subtype from MK types (cf. 1990PASP..102..565T).
While pondering all this, I was able to find that O. J. Lee retired from Dearborn Observatory seemingly the day after the catalogue was completed, and that only one of the student co-authors remained (barely) active in astronomy afterwards. Perhaps the tedium of preparing such a survey scared them off! It is easy to suspect this sociological factor contributed to the catalogue's disuse in the post-War era: no one connected with its preparation was out there publishing follow-up work on it.
All for now.
\Brian
===============================================================================
DO RA (2000) Dec mv spec Name MK Houk q
52 0 14 41.51 +03 21 50.0 8.4 K5 HD 1030 G8III 1
57 0 15 43.79 +00 07 04.8 8.3 K5 HD 1146 K0III 3
180 1 15 04.20 +01 14 02.5 8.3 K5 HD 7492 K0III 2
435 2 21 48.95 +00 58 12.1 6.9 K5 HD 14634 K0III 1
776 4 25 53.88 +01 06 56.9 8.7 K5 HD 28070 K0III: 3
1079 5 22 45.56 +00 12 33.9 8.8 K5 HD 35152 K0III 2
1533 6 22 07.02 -00 34 40.0 8.5 K5 HD 44499 K0/1III 2
267 1 39 22.82 +02 11 26.7 8.8 K5 HD 10159 K0/2 4
20 0 07 38.58 +00 10 44.7 9.6 K5 HD 295 K1III: 3
764 4 23 17.76 +00 30 35.2 9.2 K5 HD 27800 K1III 3
2384 8 00 52.26 +00 36 53.7 9.1 K5 HD 65859 K1III 2
31 0 09 57.11 +04 09 58.0 8.5 K5 HD 544 K1/2III 1
243 1 33 24.60 +05 03 06.4 9. K5 HD 9502 K1/2III 3
835 4 41 44.41 +01 17 14.7 8.9 K5 HD 29787 K1/2III 3
1162 5 32 32.56 +01 01 25.0 8.3 K5 HD 36538 K2III 2
1506 6 19 07.96 -01 22 01.0 7.5 K5 HD 43988 K2III 1
1572 6 26 20.23 +02 19 04.0 7.5 K5 HD 45212 K2III 1
1907 7 02 33.92 -04 38 05.1 7.8 K5 HD 52839 K2III 2
1977 7 09 35.13 -01 21 47.0 8.3 K5 HD 54635 K2III 3
271 1 41 25.89 +05 29 15.4 4.7 K5 HD 10380 K2/3III 1
594 3 32 38.73 +03 08 59.8 K5 HD 21976 K2/3III 1
1520 6 20 48.50 +00 44 52.6 8.0 K5 HD 44256 K2/3III 3
1810 6 52 56.30 -03 03 43.6 8.1 K5 HD 50406 K2/3III 2
2007 7 12 05.92 -01 16 07.5 8.6 K5 HD 55263 K2/3III: 3
217 1 27 07.78 +02 07 46.0 8.7 K5 HD 8827 K3III: 4
671 3 58 21.25 +01 26 45.1 8.1 K5 HD 25001 K3III 1
701 4 05 36.69 +00 10 56.9 8.6 K5 HD 25826 K3III 2
874 4 50 29.19 +01 31 39.5 8.3 K5 HD 30762 K3III 2
1290 5 47 33.54 +02 54 24.3 7. K5 HD 38675 K3III 2
1363 6 00 39.61 +04 39 18.9 8.0 K5 HD 40701 K3III: 3
1706 6 40 18.18 +03 32 28.5 8.1 K5 HD 47758 K3III 1
1804 6 52 04.20 +01 15 05.6 7.7 K5 HD 50167 K3III 1
2124 7 21 09.73 -00 58 29.2 8.0 K5 HD 57427 K3III 2
2385 8 01 02.44 +04 07 36.6 9.1 K5 HD 65858 K3III: 3
26 0 08 49.32 +01 15 15.3 9.5 K5 HD 421 K3/4 4
296 1 46 20.75 +00 04 23.0 9.0 K5 HD 10847 K3/4III 2
1081 5 23 06.13 +01 17 22.3 7.3 K5 HD 35191 K3/4III 2
2043 7 15 00.36 +01 38 15.1 8.7 K5 HD 55898 K3/4III 2
189 1 17 19.50 +01 50 28.5 7.0 K5 HD 7763 K4III 1
239 1 32 14.94 +03 41 06.6 7.5 K5 HD 9371 K4III 1
1203 5 36 42.02 -03 17 38.9 8.3 K5 HD 37207 K4III 2
1542 6 23 30.51 +04 37 35.7 8.2 K5 HD 44730 K4III: 4
1589 6 28 16.32 +04 16 45.3 8.0 K5 HD 45545 K4III 2
1864 6 58 48.63 -01 50 21.5 8.5 K5 HD 51842 K4III 2
1982 7 10 15.33 +03 53 16.1 8.9 K5 HD 54760 K4III: 3
2366 7 57 27.37 -02 56 51.1 7.6 K5 HD 65198 K4III 1
2398 8 03 58.49 +02 25 12.2 8.8 K5 HD 66486 K4III: 3
1396 6 04 56.21 +04 36 06.8 8.5 K5 HD 41362 K4/5 4
2281 7 37 28.99 -02 02 12.7 7.0 K5 HD 61095 K4/5III 1
283 1 43 59.01 +04 59 45.0 7.5 K5 HD 10652 K5III 1
675 4 00 02.13 +01 24 05.5 8.6 K5 HD 25162 K5III 3
990 5 08 44.89 +01 06 51.5 9.0 K5 HD 33222 K5III 2
2269 7 36 14.71 +02 17 08.0 8.1 K5 HD 60756 K5III 1
939 5 00 47.25 +04 34 03.5 7.0 M0 HD 32073 G8/K0III 2
1885 7 01 08.18 -00 25 09.4 8.5 M0 HD 52409 K0/1III: 3 Houk early?
1914 7 03 17.42 -04 01 04.4 8.5 M0 HD 53006 K1III 2
2122 7 21 07.54 -02 23 49.0 8.7 M0 HD 57429 K1III 3
1617 6 30 29.61 -00 16 47.3 8.4 M0 HD 45952 K1/2III 2
1382 6 02 08.08 -03 38 23.6 7.6 M0 HD 40965 K2III 3
1020 5 13 46.26 +02 22 22.0 9.4 M0 HD 33916 K2/3III: 3
626 3 39 35.07 +02 10 16.9 9.0 M0 HD 22754 K3III: 3
1246 5 40 57.68 -03 50 35.4 7.2 M0 HD 37777 K3III 1
1420 6 08 36.20 +03 08 57.5 8.5 M0 HD 42036 K3III 2
1605 6 29 13.89 -03 09 28.2 8.5 M0 HD 45772 K3III 1
1867 6 59 09.15 -03 13 49.7 8.3 M0 HD 51936 K3III 1
2188 7 26 33.30 +03 03 01.4 9.1 M0 HD 58642 K3III 3
823 4 39 14.38 +04 44 38.9 8.8 M0 HD 29539 K3/4 4
135 1 00 05.64 +02 37 58.7 8. M0 HD 5859 K4III 1
148 1 04 17.56 +00 36 55.2 7.6 M0 HD 6331 K4V 2 giant,not dwf
186 1 16 44.48 +05 03 20.3 7.6 M0 HD 7671 K4III 1
386 2 06 48.30 +01 26 31.6 7.0 M0 HD 12942 K4III 1
638 3 44 40.24 +01 56 17.8 8.0 M0 HD 23362 K4III 2
756 4 21 04.72 +01 11 39.8 7.5 M0 HD 27549 K4III 1
775 4 26 01.35 +04 22 24.4 6.5 M0 HD 28086 K4III 1
1025 5 13 47.25 +00 33 37.5 6. M0 HD 33946 K4III 1
1920 7 04 00.05 -04 37 24.6 7.2 M0 HD 53177 K4III 2
2391 8 02 03.68 -02 16 57.5 8.1 M0 HD 66121 K4III 2
570 3 24 55.82 +01 58 34.7 8.4 M0 HD 21143 K5III 2
641 3 45 34.58 +03 14 23.0 8. M0 HD 23467 K5III 1
892 4 52 11.24 +04 41 33.0 7.7 M0 HD 30961 K5III 2
1400 6 05 22.71 +00 36 46.2 6.9 M0 HD 41460 K5III 1
1479 6 17 03.78 +01 41 13.2 7. M0 HD 43588 K5III 1
2222 7 30 25.78 +03 18 25.2 7.0 M0 HD 59539 K5III 1
2231 7 31 23.64 +03 00 49.0 8.6 M0 HD 59725 K5III: 3
501 3 03 51.52 +01 01 10.6 8.9 M0 HD 19043 M1III 2
898 4 53 22.77 +02 30 29.6 5.8 M0 HD 31139 M1III 1
1910 7 03 21.00 +02 52 33.9 8.7 M0 HD 52978 M1 4
745 4 18 32.25 +04 57 07.0 7.8 M1 HD 27270 K3III 1 Houk early?
2299 7 40 49.02 +04 04 18.6 6.3 M1 HD 61721 K5III 1
1335 5 55 29.46 -02 29 21.3 7.0 M1 HD 39909 K5/M0III 3
2286* 7 38 56.78 -00 15 37.6 7.0 M1 HD 61367 K5/M0III 1
449 2 27 45.83 +04 25 53.8 8.5 M1 HD 15285 M0V 2
1845 6 56 47.65 +00 48 08.9 7.2 M1 HD 51277 M2III 1
2196 7 27 11.99 +03 33 47.4 8.1 M1 HD 58783 M2III 1
2189 7 26 34.12 +02 50 24.2 8.7 M1 HD 58643 M3III 2
287 1 44 35.95 +03 13 25.4 6.7 M2 HD 10698 K4III 1
427 2 19 19.52 +02 39 52.8 7.3 M2 HD 14362 K4/5III 1
316 1 51 34.37 +02 23 10.1 8.4 M2 HD 11338 K5III 2
2034 7 14 10.85 -03 54 06.4 6. M2 HD 55775 K5III 1
360 2 03 00.69 +02 45 44.7 8.1 M2 HD 12537 K5/M0III 1
919 4 56 49.60 +01 31 15.2 7.9 M2 HD 31542 M0III 1
1073 5 22 05.54 +03 34 17.9 7.7 M2 HD 35067 M0III 1
1640 6 34 52.57 +00 01 10.7 9.1 M2 HD 46714 M0III: 3
485 2 51 20.37 +02 10 22.1 6.9 M2 HD 17791 M1III 1
1321 5 53 29.18 -01 16 50.2 8.4 M2 HD 39573 M1III: 3
1584 6 27 06.18 -03 03 22.1 8.6 M2 HD 45417 M1III 2
2253 7 33 57.37 +03 39 05.1 7.8 M2 HD 60306 M1III 1
2365 7 57 29.13 -01 18 42.6 8.4 M2 HD 65175 M1III 1
88 0 25 26.08 +01 22 09.5 9.2 M2 HD 2115 M1/2 4
438 2 21 56.63 +00 23 44.4 6.2 M2 HD 14652 M1/2III 1
2283 7 37 56.54 -03 27 43.5 7.7 M2 HD 61200 M1/2III: 3
1769 6 47 50.00 +02 55 17.9 8.0 M2 HD 49292 M2III 2
2039 7 14 47.91 +04 09 06.8 8.2 M2 HD 55828 M2/3III 1
1999 7 11 34.69 -01 21 14.6 8.6 M3 HD 55113 K2III 2 Houk wrong?
14 0 07 19.16 +04 33 30.7 8.5 M3 HD 252 K5III 1
796 4 31 39.75 +02 10 16.7 8.4 M3 HD 28705 K5/M0III: 3
123 0 50 24.51 +03 22 52.9 8.0 M3 HD 4821 M0III 1
144 1 03 25.99 +03 15 20.1 7.5 M3 HD 6242 M0III 1
623 3 39 24.32 +03 32 49.8 8.1 M3 HD 22724 M1III 1
2354 7 54 02.13 -04 18 14.2 8.5 M3 HD 64473 M1/2III 2
76 0 20 09.54 +03 02 00.8 7.3 M3 HD 1586 M2III 1
475 2 43 18.49 +01 43 48.5 7.4 M3 HD 16971 M2III 2
717 4 11 09.35 +02 19 06.2 6.9 M3 HD 26448 M2III 1
728 4 13 24.41 +03 54 08.0 7.8 M3 HD 26691 M2III 1
1017 5 13 40.65 +03 27 51.6 9.0 M3 HD 33915 M2III: 3
2135 7 21 58.49 +03 06 28.1 8.8 M3 HD 57591 M2III 2
997 5 10 40.35 +03 59 48.4 9.5 M3 HD 33482 M2/3 4
1964 7 08 36.86 +04 10 34.1 7.1 M3 HD 54355 M4III 1
1511 6 19 59.60 -02 56 40.2 5.0 M4 HD 44131 K5III 1 Houk early?
1598 6 29 14.81 +02 38 46.3 6.0 M4 HD 45724 M1III 2
1955 7 07 46.98 -03 22 15.7 7.6 M4 HD 54219 M1III 1
847 4 44 42.76 +03 59 49.3 8.0 M4 HD 30102 M1/2III 1
787 4 29 38.94 +05 09 51.4 7.0 M4 HD 28487 M2III 1
1329 5 54 22.48 -01 04 35.3 7.0 M4 HD 39732 M2III 1
2054 7 15 20.34 +00 37 25.7 8.3 M4 HD 56001 M2III 2
11 0 07 02.43 +05 17 16.8 8.4 M4 HD 223 M3III 2
113 0 44 55.28 +03 12 03.6 7.6 M4 HD 4246 M3III 1
1352 5 58 56.54 -01 06 38.4 7.9 M4 HD 40472 M3III 1
242 1 32 58.89 +00 07 36.9 7.6 M4 HD 9473 M3/4III 1
1045 5 16 54.34 +04 39 49.5 8.0 M4 HD 34340 M3/4 4
59 0 16 39.42 +01 51 02.2 6.8 M4 HD 1228 M4III 1
1522 6 21 02.89 +02 34 07.6 8.0 M4 HD 44274 M4III 1
1559 6 24 46.94 +03 45 47.7 8.5 M4 HD 44945 M4/5III 1
2218 7 29 21.31 -04 16 43.7 M5 HD 59334 Me 3
1094 5 25 03.52 +01 11 08.2 8.1 M5 HD 35483 M2/3III 1
16 0 07 39.25 +01 20 47.9 9.3 M5 HD 293 M3III 1
1765 6 47 11.52 +01 31 45.7 8.6 M5 HD 49163 M3III 3
2028 7 13 45.34 -03 56 58.7 8.6 M5 HD 55653 M3/4III 2
972 5 06 36.11 +00 32 54.7 8.5 M5 HD 32910 M4III 1
1646 6 35 12.40 -01 30 35.8 8.1 M5 HD 46785 M4III 1
1538 6 22 43.58 -02 11 43.5 M5ep HD 44639 M4/5IIIe 1
2097 7 19 02.84 +03 31 56.3 8.3 M5 HD 56889 M5III 1
2081 7 17 31.54 +01 05 41.5 M6 HD 56567 Me 4
492 2 57 04.57 +04 30 03.7 6.2 M6 HD 18345 M2III 2 M4III SIMBAD
533 3 14 56.13 +01 36 36.9 8.7 M6 HD 20204 M3III 1
230 1 30 38.31 +02 52 54.0 M6 HD 9203 M4e -
1803 6 51 57.33 +04 45 52.5 M6 HD 50133 M5III 1
1378 6 01 46.92 -02 21 13.6 7.0 M7ep HD 40913 M6III 1
964 5 05 23.72 +01 10 39.5 N HD 32736 CS: 1
1740 6 44 40.70 +03 18 58.7 10.0 Sp HD 48664 C 4
1815 6 53 11.31 -04 34 34.1 R HD 50436 C 1
1886 7 01 01.95 -03 15 09.1 7.3 R HD 52432 C 1
2154 7 23 06.99 -04 12 48.8 9.2 R HD 57884 C 2
2177 7 25 13.06 -03 08 03.3 8.6 R HD 58385 C 1
2272 7 36 29.10 +02 04 44.2 R HD 60826 C 1
1902 7 02 06.73 -03 45 17.4 6.6 M1 HD 52690 K5III 2 Houk wrong
(VV Cep-type M1Ib supergiant)