Caldwell Catalog
109 objects in the Caldwell catalog
Caldwell Catalog
Author
Sir Patrick Moore (1923-2012)
Year
1995
Αντικείμενα
109
The Caldwell catalog is an astronomical catalog of 109 star clusters, nebulae, and galaxies for observation by amateur astronomers. It was compiled by Sir Patrick Alfred Caldwell-Moore (Patrick Moore) and published in 1995. The catalog complements the Messier catalog by including bright deep-sky objects visible from both hemispheres that were not included in Messier's original list.
Data Sources
- AstroPixels Caldwell Catalog - Complete reference with detailed information
- OpenNGC Database - Cross-referenced with NGC/IC designations
Objects are numbered C1 through C109. Unlike the Messier catalog, the Caldwell catalog includes objects visible from both northern and southern hemispheres.
Αντικείμενα
| Όνομα | NGC/IC | Τύπος | RA | Απόκλιση | Μέγ. | Αστερισμός | Ενέργειες |
|---|
Σχετικά με δεδομένα βαθέος ουρανού
Πηγή δεδομένων
Deep sky object data comes from the OpenNGC database by Mattia Verga. Coordinates, magnitudes, and object classifications are sourced from authoritative astronomical catalogs including NGC, IC, Messier, and Caldwell. Source repository: OpenNGC database
Φωτομετρικά συστήματα
V-band (Visual): Johnson V filter centered at ~550nm (yellow-green), matching peak sensitivity of human eye. This is the standard astronomical magnitude system.
B-band (Blue): Johnson B filter centered at ~440nm (blue light). Used when V magnitude is unavailable.
Κλίμακα μεγέθους
The astronomical magnitude scale is logarithmic. Each magnitude step represents a brightness ratio of ~2.512x. The formula relating magnitude difference to brightness ratio is:
\[m_1 - m_2 = -2.5 \times \log_{10}\left(\frac{F_1}{F_2}\right)\]
όπου m είναι το μέγεθος και F είναι η ροή. Μικρότερο μέγεθος = λαμπρότερο αντικείμενο.
Δείκτης χρώματος (B-V)
Ο χρωματικός δείκτης B-V υποδεικνύει το χρώμα και τη θερμοκρασία του αντικειμένου:
\[B - V = m_B - m_V\]
Typical values: blue objects have negative B-V, white objects are near 0, yellow objects are near 0.6, and red objects are above 1.0. Reference: Μετατροπή χρώματος
Σημειογραφία μεγέθους
Each magnitude value is marked with (V) for V-band or (B) for B-band to indicate the photometric system used.
Οδηγός ορατότητας:
• Όριο γυμνού ματιού: ~6.0 mag
• Κιάλια: ~10.0 mag
• Μικρό τηλεσκόπιο (4"): ~12.0 mag
• Μεσαίο τηλεσκόπιο (8"): ~14.0 mag
Σύστημα συντεταγμένων
Right Ascension (RA): Celestial longitude in hours:minutes:seconds (0h to 24h).
Declination (Dec): Celestial latitude in degrees:arcminutes:arcseconds (-90 to +90 degrees).
All coordinates are in the J2000.0 epoch (standard reference frame for year 2000).