Messier Catalog
110 objects in the Messier catalog
Messier Catalog
Author
Charles Messier (1730-1817)
Year
1774-1781
Αντικείμενα
110
The Messier catalog is a set of 110 astronomical objects catalogued by French astronomer Charles Messier in his 'Catalog of Nebulae and Star Clusters' first published in 1774. The catalog was motivated by Messier's interest in finding comets, and includes some of the most spectacular deep-sky objects visible from the northern hemisphere, including galaxies, nebulae, and star clusters.
Data Sources
- OpenNGC Database - Modern comprehensive astronomical database
- AstroPixels Messier Catalog - Complete reference with observations and images
Objects are numbered M1 through M110, with some numbers (like M102) being controversial. This catalog remains one of the most popular targets for amateur astronomers.
Αντικείμενα
| Όνομα | 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).