Vdb15

Vdb15

Commentaires sur l’objet photographié

outters-nicolasJe vous présente une nébuleuse en réflexion nommée Vdb15, pas facile car placée au nord et donc la L reste difficile à gérer à cause de la pollution lumineuse. La grosse difficulté a été l’humidité et les étoiles en ont souffert un peu.

Image LRGB

Données techniques

Données techniques de prise de vue

Object :Vdb15
Date : image du 17/18/19/23/24 octobre 2014
Optics :Tec140 F7
Mount : Paramount ME Numéro 2
Location : Orange observatory
Seeing : 3,5 à 5 !
Ccd : Proline 16803
filter wheel :FLI
filters : Astrodon LRGB
Focuser :Robofocus
Guiding : Atik 314L+
Temp. out : +10
Temp ccd : -35°
Total exposure :14h00
L 66 x 10 mn B1x1
R : 12 x 5mn b2x2
G : 12x 5mn b2x2
B : 12 x 5mn b2x2

Données scientifiques

HD 21389 is a supergiant variable star in reflection nebula VDB 15, in the constellation Camelopardalis. It is part of the Camelopardalis OB1 association. The near-identical member CS Camelopardalis lies half a degree to the north.

Observation data
Epoch J2000      Equinox J2000
Constellation Camelopardalis
Right ascension 03h 29m 54.74413s[1]
Declination +58° 52′ 43.4995″[1]
Apparent magnitude (V) 4.54[2]
Characteristics
Spectral type A0 Iae[2]
U−B color index −0.11[3]
B−V color index +0.56[3]
Variable type α Cyg[4]
Astrometry
Radial velocity (Rv) −6.20[5] km/s
Proper motion (μ) RA: 1.79[1] mas/yr
Dec.: −1.09[1] mas/yr
Parallax (π) 1.30 ± 0.56[1] mas
Distance 975[3] pc
Absolute magnitude (MV) −7.20[3]
Details[2]
Mass 19.3 M☉
Radius 97 R☉
Luminosity 55,000 L☉
Surface gravity (log g) 1.75 cgs
Temperature 9,730 K
Rotation 25
Age 11[3] Myr
Other designations
CE Camelopardalis, BD+58°607, HIP 16281, HR 1040, HD 21389, SAO 24061

Since 1943, the spectrum of CE Cam has served as one of the stable anchor points by which other stars are classified.[6]

CE Camelopardalis is some 19 times as massive as the Sun and 55,000 timers as luminous. Hohle and colleagues, using the parallax, extinction and analysis of spectrum, came up with a mass 14.95 ± 0.41 times that and luminosity 62,679 times that of the Sun.[7]

CE Cam is embedded in a large dusty molecular cloud, part of which it illuminates as a reflection nebula (vdB15 or BFS 29). This is a region of ongoing star formation with stars aged from one to a hundred million years old. CE Cam itself is thought to be around 11 million years old, long enough to have exhausted its core hydrogen and evolved away from the main sequence into a supergiant