Caldwell Catalog
109 objects in the Caldwell catalog
Caldwell Catalog
Author
Sir Patrick Moore (1923-2012)
Year
1995
天體
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.
篩選天體
| 名稱 | NGC/IC | 類型 | 赤經 | 赤緯 | 星等 | 星座 | 操作 |
|---|
關於深空數據
資料來源
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
測光系統
V-band (Visual): Johnson V 濾鏡的中心波長約為 550nm（黃綠光），對應人眼靈敏度的峰值。這是標準的天文星等系統。
B-band (Blue): Johnson B 濾鏡的中心波長約為 440nm（藍光）。在沒有 V 星等時使用。
星等尺度
天文星等尺度是對數式的。每一級星等代表約 2.512 倍的亮度比。將星等差與亮度比關聯起來的公式為：
\[m_1 - m_2 = -2.5 \times \log_{10}\left(\frac{F_1}{F_2}\right)\]
其中 m 為星等，F 為通量。星等越低 = 天體越亮。
色指數（B-V）
B-V 色指數表示天體的顏色與溫度：
\[B - V = m_B - m_V\]
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: 色彩轉換
星等表示法
每個星等值都以 (V) 表示 V 波段或以 (B) 表示 B 波段，以指示所使用的測光系統。
可見度指南：
• 肉眼極限：約 6.0 星等
• 雙筒望遠鏡：~10.0 星等
• 小型望遠鏡（4"）：~12.0 星等
• 中型望遠鏡（8"）：~14.0 星等
坐標系
Right Ascension (RA): Celestial longitude in hours:minutes:seconds (0h to 24h).
Declination (Dec): Celestial latitude in degrees:arcminutes:arcseconds (-90 to +90 degrees).
所有座標均採用 J2000.0 曆元（2000 年的標準參考框架）。