Globular Cluster in Cans Ventatici

Information about M 3

Basic object information

Object name: M 3

Object type: Globular cluster

Magnitude: 6.3

Size: 18.0'

Position information

Apparent RA: 13h 42m 52s

Apparent Dec: +28° 18' 21"

Constellation: Canes Venatici

Altitude: 28° 20' 21"

Azimuth: 69° 47' 33"

Hour angle: 19h 20m 50s

Rise: 13h 39m 57s

Transit: 20h 38m 57s

Set: 3h 41m 54s

Names and designations

M 3

NGC 5272

GCL 25

Star atlas chart numbers

Herald-Bobroff Astroatlas: Chart C-29

Millennium Star Atlas: Charts 651-652 (Vol II)

Sky Atlas 2000.0: Chart 7

Uranometria 2000: Chart 110, Vol 1

Revised NGC/IC Catalog Data

(Wolfgang Steinicke, Jan 2003)

Names and designations

NGC 5272

M 3

GCL 25

Catalog information

Type of object: Globular cluster

RA (J2000.0): 13h 42m 11.2s

Dec (J2000.0): +28° 22' 34"

V Magnitude: 6.3

Size: 18.0'

Classification: VI

Saguaro Astronomy Club v7.2 Catalog Data

Saguaro Astronomy Club, August 2000

Names and designations

M 3

NGC 5272

Catalog information

Type of object: Globular cluster

RA (J2000.0): 13h 42m 12.0s

Dec (J2000.0): +28° 23' 00"

Constellation: Canes Venatici

Magnitude: 6.4

Surface brightness: 11.0

Size: 18.6'

Object classification: VI

Description: !!,eB,vL,vsmbM,st 11..

Notes: Lord Rosse-sev dark marks within 5' of center

Harris Globular Cluster Catalog Data

A catalog of parameters for globular clusters on the Milky Way, Harris W.E., Astron. J. 112, 1487 (1996, rev. 15 May 1997)

Names and designations

Cluster identification number: NGC 5272

Other commonly used cluster name: M 3

Position information

RA (J2000.0): 13h 42m 11.2s

Dec (J2000.0): +28° 22' 32"

Galactic longitude: 42.21°

Galactic latitude: 78.71°

Distance from the Sun: 10.0 kpc

Distance from the galactic centre: 11.9 kpc

Sun-centred position components:

X: 1.5 kpc (towards galactic centre)

Y: 1.3 kpc (in direction of galactic rotation)

Z: 9.8 kpc (towards north galactic pole)

Brightness and colour information

Foreground reddening: 0.01 magnitudes

V magnitude of the horizontal branch: 15.65

Apparent visual distance modulus: 15.04 magnitudes

Integrated V magnitude of the cluster: 6.19

Absolute visual magnitude: -8.85

Integrated B-V colour index: 0.69

Integrated V-I colour index: 0.93

Specific frequency of RR Lyr: 75.3

Horizontal-branch ratio: 0.08

Dickens horizontal-branch morphological type: 4

Metallicity in log10 scale (Sun=1): -1.57

Integrated spectral type: F6

Radial velocity information

Heliocentric radial velocity: -148.6 km/sec

Observational uncertainty in heliocentric radial velocity: 0.4 km/sec

Radial velocity relative to Solar local standard of rest: -138.0 km/sec

Physical information

Central concentration [log10(Rt/Rc)]: 1.85

Core radius: 0.50 arc minutes

Half-mass radius: 1.12 arc minutes

Log (base 10) of core relaxation time: 8.78 yr

Log (base 10) of core relaxation time at the half-mass radius: 9.02 yr

Central surface brightness in V band: 16.34 mag/sq arc sec

Log (base 10) of central luminosity density: 3.56 solar luminosities per cubic parsec