Если коротко ответить, то тогда...
Вот страница http://cdsarc.u-strasbg.fr/viz-bin/Cat?I/268 с описанием UCAC1
а вот страница http://cdsarc.u-strasbg.fr/viz-bin/Cat?I/289 с описанием UCAC2.
The UCAC1 is a high density, highly accurate, astrometric catalog of over 27 million stars in the Southern Hemisphere in the magnitude range of about 8 to 16.
The UCAC2 is a high density, highly accurate, astrometric catalog of 48,330,571 stars covering the sky from -90 to +40 degrees in declination and going up to +52 degrees in some areas. The northern limit is a function of right ascension.
Есть у меня версия каталога UCAC1 для Cartes du Ciel, а сейчас работаю над каталогом UCAC2.
Кроме того, сделаю "северную добавку" I/294 The UCAC2 Bright Star Supplement (Urban+, 2004)
Его страница с описанием на
http://cdsarc.u-strasbg.fr/viz-bin/Cat?I/294Данные каталоги будут доступны на диске.
Могу переслать желающим.
P.S. А вот описание файлов каталога.
Byte-by-byte Description of file: out.sam
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Bytes Format Units Label Explanations
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1- 8 I08 --- 2UCAC [00000001,48330571] UCAC designation (1)
10- 20 F11.7 deg RAdeg Right ascension (degrees), ICRS, Ep=J2000 (2)
21- 31 F11.7 deg DEdeg Declination (degrees), ICRS, Ep=J2000 (2)
33- 35 I3 mas e_RAdeg Minimal mean error on RAdeg (3)
37- 39 I3 mas e_DEdeg Minimal mean error on DEdeg (3)
41- 43 I3 mas ePos Error of original UCAC observation (4)
45- 49 F5.2 mag UCmag Magnitude in UCAC system (579-642nm) (5)
51- 52 I2 --- No Number of UCAC observations for the star
54- 55 I2 --- Nc Number of catalog positions used for pmRA, pmDE
58- 59 I02 --- cfl Major catalogs used in pmRA, pmDE (6)
61- 68 F8.3 yr EpRA Central epoch for mean RA (3)
70- 77 F8.3 yr EpDE Central epoch for mean Declination (3)
79- 86 F8.1 mas/yr pmRA Proper motion in RA(*cos(Dec)) (7)
88- 95 F8.1 mas/yr pmDE Proper motion in Dec
97-100 F4.1 mas/yr e_pmRA Mean error on pmRA (
102-105 F4.1 mas/yr e_pmDE Mean error on pmDE (
107-111 F5.2 --- qpmRA Goodness of fit for pmRA (
113-117 F5.2 --- qpmDE Goodness of fit for pmDE (
119-128 I10 --- 2Mkey 2MASS (II/246) Unique source identifier
130-135 F6.3 mag Jmag ? J magnitude (1.2um) from 2MASS
137-142 F6.3 mag Hmag ? H magnitude (1.6um) from 2MASS
144-149 F6.3 mag Kmag ? K magnitude (2.2um) from 2MASS
151-153 I03 --- phf 2MASS photometric quality flag (9)
155-157 I03 --- ccf 2MASS confusion flag (10)