NGC Catalog
8373 objects in the NGC catalog
Novi splošni katalog
Author
John Louis Emil Dreyer (1852-1926)
Year
1888
Objekti
7840
The New General Catalogue of Nebulae and Clusters of Stars (NGC) is an astronomical catalogue compiled by John Louis Emil Dreyer in 1888. It contains 7,840 deep-sky objects and is one of the most comprehensive catalogs of its kind. The NGC expanded upon previous catalogs and remains a fundamental reference for astronomers today.
Data Sources
- OpenNGC Database - Modern digitized version with corrections and updates
- Wikipedia - New General Catalogue - Historical background and detailed information
Objects are numbered NGC 1 through NGC 7840. Many objects have been reclassified or found to be duplicate entries since the original catalog was published.
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| Ime | Vrsta | RA | Dek | Mag | Ozvezdje | Dejanja |
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O podatkih globokega neba
Vir podatkov
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
Fotometrični sistemi
V-band (Visual): Johnson V filter s središčem pri ~550nm (rumeno-zelena), ki ustreza vrhunski občutljivosti očesa. To je standardni astronomski sistem magnitud.
B-band (Blue): Johnson B filter s središčem pri ~440nm (modra svetloba). Uporablja se, ko magnitude V ni na voljo.
Lestvica magnitud
Astronomska lestvica magnitud je logaritmična. Vsak korak magnitude predstavlja razmerje svetlosti ~2,512. Formula:
\[m_1 - m_2 = -2.5 \times \log_{10}\left(\frac{F_1}{F_2}\right)\]
kjer je m magnituda in F tok. Nižja magnituda = svetlejši objekt.
Barvni indeks (B-V)
Barvni indeks B-V označuje barvo in temperaturo objekta:
\[B - V = m_B - m_V\]
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: Pretvorba barv
Oznaka magnitude
Vsaka vrednost magnitude je označena z (V) za V-pas ali (B) za B-pas za označevanje uporabljenega fotometričnega sistema.
Vodnik vidljivosti:
• Meja prostega očesa: ~6,0 mag
• Daljnogled: ~10,0 mag
• Mali teleskop (4"): ~12,0 mag
• Srednji teleskop (8"): ~14,0 mag
Koordinatni sistem
Right Ascension (RA): Celestial longitude in hours:minutes:seconds (0h to 24h).
Declination (Dec): Celestial latitude in degrees:arcminutes:arcseconds (-90 to +90 degrees).
Vse koordinate so v epohi J2000.0 (standardni referenčni okvir za leto 2000).