emil@rochester.UUCP (08/16/85)
From: Emil Rainero <emil>
I thought it would be fun to write some star display software on my Macintosh
using the public domain Yale Bright Star Catalog. This would be a public domain,
cooperative effort. Since Rochester's bookstores think astronomy and astrology
are equivalent, I need some simple algorithms and data.
1. Star, Planetary, Lunar positional algorithms for any date/time.
2. Boundaries of the constellations.
3. Mapping from spherical coordinates (RA,DEC) to a two dimensional plane
for screen display.
I'll take algorithms or references. What I would love to do is write a
generic C program that would include all of the algorithms in their
mathematical as well as code form. It is really impossible to figure out
an algorithm that has been hacked in BASIC. I'm not saying that C is any
better, just that the comments should include the algorithms the code is
implementing. I will summarize all responses as well as donate the source
code, with all Macintosh dependencies separated for portability.
The mapping from (RA,DEC) to (x,y) should preserve the spherical nature of
the data. If anyone else has run the algorithm in Astronomy magazine, they
were probably as disappointed as I was when centering on Polaris. I was
expecting to see something similar to a star map.
If anyone knows of a better machine readable database, please let me know.
Wouldn't it also be great if the program ran like a database (it will)
so you could query for all Messier, or double stars, or ones within a spectral
range. Imagine having all of the following information available about
10,000 stars.
*****************************************************************
* *
* YALE CATALOGUE OF BRIGHT STARS *
* *
* DOCUMENTATION FOR THE MACHINE-READABLE VERSION OF *
* THE YALE CATALOGUE OF BRIGHT STARS *
* R-SAW-7/79-36 *
* *
*****************************************************************
The YALE CATALOGUE OF BRIGHT STARS is in the public domain, and
this documentation on the catalogue was extracted almost verbatum
from a booklet, also in the public domain, whose preparation
was funded by:
National Aeronautics and Space Administration
Goddard Space Flight Center
Greenbelt, Maryland 2077l
under contract NAS 5-25369 by:
Theresa A. Nagy
Systems and Applied Sciences Corporation
6811 Kenilworth Avenue
Riverdale, Maryland 20840
This database is revision 3 of the Yale Catalogue of Bright Stars,
and it was obtained on 9 track tape on March 17, 1981 from:
Dr. Wayne Warren
National Space Science Data Center
Code 601
Godard Space Center
Greenbelt, Md 20771
Dr. Warren says that revision 4 of the catalogue is due in late
1981, and that it will have revisions in the magnitude and color
data for about 10% of the stars. The National Space Science Data
Center does NOT have the capability of supplying the data base
or revisions on floppy disks.
The people who funded the documentation of this catalog, and the
people who did the documentation work for a living. PLEASE DO
NOT MAKE THEM COMPLETLY UNPRODUCTIVE BY CALLING THEM UP FOR
INFORMATION.
*****************************************************************
* *
* Section 1 - Introduction *
* *
*****************************************************************
In recent years there has been a trend away from publishing
catalogues in book form to preparing catalogues by computer
and distributing them on magnetic tape, with appearance in
book form as a secondary occurrence. This memo is the result
of the development of the documentation for the machine-
readable version of the catalogue and includes the basic
information given the origional preface of the published
catalogue. This memo should be distributed along with any
copy of the machine-readable version of the catalogue.
*****************************************************************
* *
* Section 2 - Tape Contents *
* *
*****************************************************************
A byte-by-byte description of the contents of the catalogue
is given in Table 2-1. The information in the "Description"
column is derived mainly from the published version of the
catalogue whenever possible. The "Suggested Format" column
is for FORTRAN-formatted reads.
**************** Table 2-1 Tape Contents ***********************
Byte Description Format
1-4 Yale Bright Star (BS) I4
(= Harvard Revised (HR) Number)
5-7 Flamsteed Number I3
8-14 Name 7A1
(Greek letters coded: alpha = 0l . .
omega = 24)
15 Sign of Bonner Durchmusterung (BD) A1
16-22 DM Number I7
23-28 Henry Draper (HD) Number I6
29-33 Boss General Catalog (GC) Number I5
34-37 Trig. Parallax Catalogue Number I4
(when followed by decimal - 1963
Supplement)
38-43 Radial Velocity Catalogue Number I6
44 Double Star Catalogue A1
b - implies Aitken's Catalogue of
Double Stars
R - implies Rossiter's Catalogue of
Southern Double Stars
Other catalogues or lists unnumbered,
are represented be letters:
I - Innes
F - Finsen
K - Kuiper
B - van Biesbroeck or van den Bos
45-49 Catalogue Number I5
50-51 Blank or letters indicating componets 2A1
of multiple-star system.
52-59 Variable Star Catalogue 8A1
(1958 or 1961 Supplement, suspected
but unconfirmed variables are
represented by "VAR?"left justified)
60-65 ***** Right Ascension (epoch 1900.0) *****
60-61 Hours I2
62-63 Minutes I2
64-65 Seconds I2
66 Sign of Ten-Year change in Right Ascension A1
67-69 Ten-Year change in Right Ascension I3
(unit = seconds)
70-74 ***** Declination (epoch 1900.0) *****
70 Sign A1
71-72 Degrees I2
73-74 Minutes I2
75-79 ***** Galactic Longitude *****
75-77 Degrees I3
78-79 Minutes I2
80-84 ***** Galactic Latitued *****
80 Sign A1
81-82 Degrees I2
83-84 Minutes I2
85-88 BS-HR Number I4
89-94 ***** Right Ascension (epoch 2000.0) *****
89-90 Hours I2
91-92 Minutes I2
93-94 Seconds I2
95-99 ***** Change in Right Ascension *****
****** (epoch 2000.0 - 1900.0) ******
95 Sign A1
96-97 Minutes I2
98-99 Seconds I2
100-104 ***** Declination (epoch 2000.0) *****
100 Sign A1
101-102 Degrees I2
103-104 Minutes I2
105-107 ***** Change in Declination *****
**** (epoch 2000.0 - 1900.0) ****
105 Sign A1
106-107 Minutes I2
108-111 ***** Visual Magnitude *****
108 Sign A1
(if minus (-) magnitude)
109-111 Visual Magnitude I3
(unit = 0.01 magnitude)
112-113 Source: 2A1
b - Indicates photoelectric determination
by UBV System
R - Indicates HR magnitudes reduced by
Rybka to V system
H - Indicates original HR magnitude was
was retained
B - Indicates blended images
***** Color *****
114 Sign A1
115-117 B-V in UBV System I3
(unit = 0.01 magnitude)
118-139 Spectral Class 22A1
(if composit spectral class,
plus (+) in byte 139)
140 Sign A1
141-144 value I4
(unit = 10^-3 arcsec)
145-149 ***** Annual Proper Motion in Declination *****
145 Sign A1
146-149 Value I4
(unit = 10^-3 arcsec)
150-154 ***** Parallax *****
150 Sign A1
151-153 Trigonometric Parallax I3
(unit = 10^-3 arcsec)
154 D indicates Dynamical Parallax, which is A1
given only when Trigonometric Parallax
is not available
155-160 ***** Radial Velocity *****
155 Sign A1
156-160 Velocity (km/sec) 5A1
("V?" appears not right justified)
***** Double Star Data *****
161-163 Magnitude difference between two componets I3
of a visual binary, or between two brightest
componets of a multiple system from the
double star catalog, which may be inconsistent
with the values given in bytes 107-110.
(unit = 0.01 magnitude)
164-167 Maxium observed separation of the same two I4
componets acording to the paticular catalog
cited.
(unit = 0.1 arcsec)
168 Number of componets having lettered I1
designations in the catalog of double stars.
169-170 Remarks:
1 - The companion is optical.
2 - Visual binary.
3 - Common proper motion componets.
4 - Fixed-seperation companion.
5 - Two spectra are indicated on the
radial velocity plates.
6 - The star is a spectroscopic binary.
7 - Magnitude and color given refer to
the combined light of two or
more stars.
The following letters refer to types of
remarks that appear in the book form of
the catalogue:
D - Double star data.
G - Cluster, group, aggregate, or
association membership.
M - Comments on magnitude or color, except
data on known variable stars.
N - The name of a bright star.
R - Radial velocity comments, including
data on spectroscopic binaries.
S - Comments on Spectra.
V - Remarks on variable stars other than
the data from General Catalogue of
Variable Stars and its Supplement,
which are abstracted in the Remarks
for all stars with named variable
star designations.
* - Any combination of the above categories
and other comments not falling under
any of those categories.
171-178 Right ascension (1900) in radians F8.4
179-186 Declination (1900) in radians F8.4
187-194 Right ascension (2000) in radians F8.4
195-202 Declination (2000) in radians F8.4
*****************************************************************
* *
* Section 4 - Remarks and Modifications *
* *
*****************************************************************
The magnetic tape version of the Third Revised Edition
of the Catalogue of Bright Stars (1964, Yale University
Observatory) was received in 1972 from the U. S. Naval
Observatory. This version of the catalogue had seperate
data files for the left-hand and the right-hand pages of
the catalogue. Listed below are the modifications to
that version.
1. Overpunches existed in several fields. These
fields were decoded and all amperstands were
converted to plus (+) signs.
2. Right-hand and left-hand page dara were merged
into one data file.
3. The tape was converted from a 7-track to a
9-track tape.
4. The record size was expanded from 84 bytes
(each page with overpunches included) to
202 bytes.
5. All published errata (cf. table 4-1) have been
incorporated in the magnetic tape version.
6. One star (BS 1612) was found to have a blank
magnitude field which when read with a FORTRAN
F format yielded a zero value. This field was
corrected to 3.8 as per the published catalogue.
7. The double star number or leter was not right
or left justified. The bytes containing this
information were modified so that only the
number appears in bytes 45-49 and the letter
portion of the identification appears only in
bytes 50-5l.
8. The equatorial coordinates at both epochs 1900
and 2000 were computed in radians and added to
each record.
In addition to the published errata other identification
errors have been noted over the past years. These possible
errors are listed below for reference but the corrections
have not been made to the machine-readable version (except
for star BS 1101) of the catalogue since they do not
constitute a published set of errata.
BS # Published Value Correction
67 DM +1 degree 28 DM +0 degree 28
1101 DM -1 degree 572 DM -0 degree 572
6165 B-V +0(m/.)26 B-V -(m/.)26
7705 HD 191570 HD 191571
8417 HD 209790 HD 209791
8841 HD 219449 HD 219430
***** (m/.) was printed as a "." with a "m" directly above
***** the "."
The second edition of the Yale Bright Star Catalogue
(1940) included all except 19 of the 9110 stars first
listed in the Harvard Annals (Volume 50, 1908), the "HR"
catalogue whose numbering was exactly taken over in the
Yale Bright Star Catalogue (YBS). There are 19 blank
records in both the published version of the catalogue
as well as the machine-readable version of the YBS.
There are 9091 records with information, and 19
records with just the HR number (the remainder of the
record is blank). The HR stars which are blank are
given below.
92 95 182 663 1057
1630 1841 2472 2496 3515
3671 6309 6437 6515 7138
7189 7539 8296 8945
In addition to the information given in the Catalogue
of Bright Stars - Third Revised Edition, the value of
the 10-year change in the right ascension (bytes 66-69)
is given plus the equatorial coordinates at both epochs
(1900 and 2000) in radians (bytes 171-202).
The published version of the catalogue had sign errors
for the stars listed in Table 4.2. For all of the stars
listed a minus sign should appear for the sign of the
galactic latitude in the hard copy, the magnetic tape
version is correct.
It should be noted that more stars have colors on the
machine-readable version of this catalogue than given
in the published version of the catalogue. Also,
sometimes the spectral type differs from that as listed
in the Third Revised Edition (e.g. HR 72 is given as
a G0 star in the published catalogue but as a G5 IV-V
star on the tape). It is unclear what or who is the
source of these updates.
******** Table 4-1 Published errata in the Third Edition ********
BS # Column For Read
472 R blank 3
967 Radial Velocity -65 -6
969 Radial Velocity +22 +2
1210 Double Srars:
delta m blank 4.2
Sep blank 75.3
No blank 3
1966 RA (2000) 2x 27
2063 DM 11711 1171a
2402 DM 136 1136
2564 Dec (1900) 1' 18'
3366 HD 72622 72292
3445 B-V -0.71 +0.71
3759 Radial Velocity +98 +10
3962 HD 87330 87318
4101 R blank 1
4450 delta alpha 5v 55
5422 R 2 1
5703 Dec (1900) + -
Galactic Long 20 deg 59' 347 deg 43'
Galactic Lat +53 deg 21' +34 deg 3'
Dec (2000) +14 deg 49' -15 deg 33'
5839 Radial Velocity +8 +4
6206 Double Stars: Sep 957. 95.7
6616 B-V +1.16 +0.70
6622 Spectral Class B35 B3V
6984 RA (1900) 27s 37s
Galactic Long l' 2'
Galactic Lat 5' 3'
RA (2000) 4s 14s
7257 Radial velocity +16 +13
7517 HD 186648 186675
7543 R blank 1
7567 Variable Star Cat V Cyg V280 yg
7645 R blank 1
8225 R blank 1
8570 HD 213306 213296
8571 HD 213307 213306
8833 R blank 1
********** Table 4-2 Stars with sign error of the **************
********** galactic latitude in the published catalogue. ********
93 488 561 839 964 1046 1073 1324
1330 1550 1612 1615 1689 1779 1795 1805
1843 1850 1914 1945 2074 2116 2135 2184
2223 2250 2253 2269 2287 2342 2362 2385
2404 2422 2432 2441 2474 2479 2517 2530
2582 2622 2639 2694 2723 2796 2825 2853
2923 2992 3004 3034 3099 3113 3160 3170
3177 3237 3237 3242 3253 3267 3270 3296
3327 3328 3520 3588 3614 3784 3837 3875
3920 4091 4095 4114 4144 4147 4169 4177
4179 4188 4198 4210 4228 4239 4271 4487
4499 4511 4541 4573 4599 4603 4644 4729
4730 4730 4781 4771 4830 4972 5171 5349
5459 5460 5546 5873 5937 6197 6381 6392
6398 6450 6456 6522 6700 6716 6724 6727
6762 6798 6825 6838 6858 6946 6973 7158
7315 7331 7332 7357 7437 7458 7472 7490
7540 7670 7743 7770 7826 7911 7926 7984
8023 8035 8053 8064 8107 8136 8161 8185
8206 8259 8677 8745 8797 8803 8894 8990
9100
***** note: due to the poor quality of the photoreduced
***** printout, 5s, 6s, 8s, & 9s may have been mistaken
***** each other.
Emil Rainero
UUCP: (..!{allegra, decvax, seismo}!rochester!emil)
ARPA: emil@rochester.arpa
USmail: Emil Rainero, Dept. of Comp. Sci., U. of Rochester, NY 14627.
Phone: Office: (716) 275-5365 Home: (716) 473-1150