IC Catalog
5596 objects in the IC catalog
Profunda Ĉielo
Author
John Louis Emil Dreyer (1852-1926)
Year
1895, 1908
Objektoj
5386
The Index Catalogue (IC) is an astronomical catalogue compiled by John Louis Emil Dreyer and published in two parts in 1895 and 1908 as supplements to the New General Catalogue. The IC contains 5,386 objects that were discovered after the NGC was published, continuing the systematic cataloging of deep-sky objects.
Data Sources
- OpenNGC Database - Modern digitized version with corrections and updates
- Wikipedia - Index Catalogue - Historical background and detailed information
Objects are numbered IC 1 through IC 5386. The IC was created to supplement the NGC with newly discovered objects and corrections.
Objektoj
| Nomo | Tipo | RA | Dek | Mag | Konstelacio | Agoj |
|---|
Pri profundaĉiel-datumoj
Fonto de datumoj
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
Fotometriaj sistemoj
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.
Magnituda skalo
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:
\[m_1 - m_2 = -2.5 \times \log_{10}\left(\frac{F_1}{F_2}\right)\]
kie m estas magnitudo kaj F estas fluo. Pli malgranda magnitudo = pli brila objekto.
Kolorindekso (B-V)
La kolorindekso B-V indikas la koloron kaj temperaturon de la objekto:
\[B - V = m_B - m_V\]
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: Kolora konvertado
Magnituda notacio
Each magnitude value is marked with (V) for V-band or (B) for B-band to indicate the photometric system used.
Gvidilo pri videbleco:
• Limo por nuda okulo: ~6.0 mag
• Binokloj: ~10.0 mag
• Malgranda teleskopo (4"): ~12.0 mag
• Meza teleskopo (8"): ~14.0 mag
Koordinata sistemo
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).