Michigan Catalogue of two dimensional spectral types for the HD stars.
(Vol.1, -90deg < {delta} < -53deg)
Houk N., Cowley A.P.
<Ann Arbor, Univ. of Michigan (1975)>
Description:
This is the first of three volumes of the University of Michigan's catalogs of stellar spectral types for stars in the Henry Draper (HD) Catalog. (See catalogs 3051B and 3080 for volumes 2 and 3). It is part of a program of systematic reclassification in the MK system of the entire Henry Draper Catalogue (HD). This catalog (volume 1) includes all HD stars having declinations (1900.0) between -90 deg. and -53 deg. The stars were classified visually on objective-prism plates taken with the Michigan Curtis-Schmidt telescope at Cerro Tololo Inter-American Observatory. The 4-degree + 6-degree prisms yield a dispersion at H-gamma of 108 angstroms/mm, with a resolution of about 2 angstroms/mm, comparable to that of the original MK system. The spectra were taken on IIaO emulsion photographic plates and were widened to 0.8 mm, with exposures of 20-, 4-, and 1-min.
The machine-readable catalog includes HD number, spectral type, a quality estimate, the photographic magnitude from the HD catalog, right ascension and declination (1900.0), centennial precessions, galactic coordinates, and cross identifications to the numbering systems of the HD, CD, and CPD catalogs. Separate files contain a list of the plate codes and the remarks referenced in the main catalog file.
File Summary:
| FileName | Lrecl | Size | Records | Explanations |
| ReadMe | 80 | 7KB | This file | |
| adc.doc | 126 | 26KB | 936 | ADC Documentation |
| vol1.dat | 107 | 753KB | 36382 | The Catalogue, Vol.1 |
| rem1.dat | 315 | 59KB | 4636 | Remarks of Vol.1 |
| plates.dat | 32 | 4KB | 479 | List of Plate Codes |
See also:
3051B : Volume 2 of this catalog (additional declination zones)
3080 : Volume 3 of this catalog (additional declination zones)
3133 : Volume 4 of this catalog (additional declination zones)
Byte-by-byte Description of file: vol1.dat
| Bytes | Format | Units | Label | Explanations |
| 1-6 | I6 | HD | Henry Draper Catalog (HD) number | |
| 7 | A1 | Case | [*] '*' = sp. type lower case in printed ver. | |
| 8 | A1 | n_SpType | [+] '+' if spectral type is from HD Catalog | |
| 9-24 | A16 | SpType | The Spectral type | |
| 26 | A1 | Ave_Flag | *[A] 'A' if classification used is an average | |
| 27 | I1 | q_SpType | [1/4]? Quality of the classification, see ADC document (adc.doc) | |
| 29-32 | A4 | Remark | Remark (see adc.doc, Table 4-2) | |
| 34-39 | F6.2 | mag | Ptg | Photographic magnitude from HD catalog |
| 40 | A1 | Var_Flag | [V] 'V' if star is known or suspected variable | |
| 42-43 | I2 | h | RAh | Hours RA, epoch 1900.0 |
| 45-48 | F4.1 | min | RAm | Minutes RA, epoch 1900.0 |
| 50 | A1 | DE- | Sign Dec, epoch 1900.0 | |
| 51-52 | I2 | deg | DEd | Degrees Dec, epoch 1900.0 |
| 54-55 | I2 | arcmin | DEm | Minutes Dec, epoch 1900.0 |
| 57-61 | F5.1 | 0.01min/yr | precRA | *Centennial precession in RA |
| 63-65 | I3 | 0.01arcmin/yr | precDec | Centennial precession in Dec |
| 67-71 | F5.1 | deg | GLON | Galactic longitude |
| 73-77 | F5.1 | deg | GLAT | Galactic latitude |
| 78-87 | A10 | CPD | *Cape Photographic Durchmusterung Designation | |
| 89-91 | A3 | Plate1 | * Plate code #1 | |
| 93-95 | A3 | Plate2 | * Plate code #2 | |
| 97-99 | A3 | Plate3 | * Plate code #3 | |
| 101-103 | A3 | Plate4 | * Plate code #4 | |
| 105-107 | A3 | Plate5 | * Plate code #5 |
Note on Ave_Flag:
In this case, q_SpType is assigned the highest of the qualities used in forming the average.
Note on CPD:
'CP' in bytes 78-79, -ZZNNNNN in bytes 80-87
Note on precRA:
Very near the south pole, some of the precessions are larger than -99.9 min/century and these values are in the remarks.
Note on Plate*:
Each plate has its own identification code (see file plates.dat)
Byte-by-byte Description of file: rem1.dat
| Bytes | Format | Units | Label | Explanations |
| 1-6 | I6 | HD | Henry Draper Catalog (HD) number | |
| 7-315 | A309 | Remark | Remarks in free form text |
Byte-by-byte Description of file: plates.dat
| Bytes | Format | Units | Label | Explanations |
| 1-3 | A3 | Code | Plate code | |
| 7-11 | I5 | Number | Plate Number | |
| 15-32 | A18 | Date | Exposure date |
Historical Notes:
* 09-Nov-1993: list of plates added at CDS
* 08-Dec-1994: list of plates corrected by Shiro Nishimura [ADAC/NAOJ]
* 17-Sep-1996: brief description added by James Gass [NASA/SSDOO/ADC]
(End) Francois Ochsenbein [CDS] 08-Dec-1994