(Ref) Object type as listed in the reference "Ref"
(acronym) Object type linked to the acronym according to the original reference
() Anterior to 2007, before we can link the objet type to a reference, or given by the CDS team in some particular cases
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
ra dec : right ascension and declination (unit and frame defined according to your Output Options)
Grey values are increasing the original precision due to the computation of frame transformations
(wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
[error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
position angle (in degrees North celestial pole to East)
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
ra dec : right ascension and declination (unit and frame defined according to your Output Options)
Grey values are increasing the original precision due to the computation of frame transformations
(wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
[error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
position angle (in degrees North celestial pole to East)
quality : flag of quality
E ≥ 10"
D : 1-10" (and some old data)
C : 0.1-1"
B : 0.01-0.1" + 2MASS, Tyc
A : VLBI, Hipparcos
bibcode : bibcode of the coordinates reference
FK5
coord.
(ep=J2000 eq=2000) :
18 08 40.314 -20 24 41.12
[
60 60 90
]
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
ra dec : right ascension and declination (unit and frame defined according to your Output Options)
Grey values are increasing the original precision due to the computation of frame transformations
(wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
[error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
position angle (in degrees North celestial pole to East)
quality : flag of quality
E ≥ 10"
D : 1-10" (and some old data)
C : 0.1-1"
B : 0.01-0.1" + 2MASS, Tyc
A : VLBI, Hipparcos
bibcode : bibcode of the coordinates reference
FK4
coord.
(ep=B1950 eq=1950) :
18 05 41.671 -20 25 12.54
[
60 60 90
]
Syntax of coordinates is : "ra dec (wtype) [error ellipse] quality bibcode" :
ra dec : right ascension and declination (unit and frame defined according to your Output Options)
Grey values are increasing the original precision due to the computation of frame transformations
(wtype) : wavelength class for the origin of the coordinates (Rad, mm, IR, Optical, UV, Xray, Gam)
[error ellipse] : measurement uncertainty, on (ra,dec) if the positional angle is 90 degrees, on (majaxis,minaxis) otherwise (in mas at defined epoch in the original catalogue),
position angle (in degrees North celestial pole to East)
quality : flag of quality
E ≥ 10"
D : 1-10" (and some old data)
C : 0.1-1"
B : 0.01-0.1" + 2MASS, Tyc
A : VLBI, Hipparcos
bibcode : bibcode of the coordinates reference
Gal
coord.
(ep=J2000) :
009.997460 -00.245450
[
60 60 90
]
Spectral type is made of 3 parts:
%coding is composed of 4 parts :
the spectral type, which is made of a
temperature class, eventually a luminosity class (roman number)
and/or spectral peculiarities;
References (3 between 2019 and 2024) (Total 42)
Simbad bibliographic survey began in 1850 for stars (at least bright stars) and in 1983 for all other objects (outside the solar system).
Follow
new references on this object
Collections of Measurements
Warning : measurements from IRAS, IRC, SAO, CL.g (ACO), GJ have been removed
(they are still available using the icon Vizier near the identifier of the catalogue, or at the bottom of the page in the section "External links" to get the full data)
Indications mainly about references on other documents
Notes (1) :
NAME LBV 1806-20 is the named assigned to the very massive star
discovered by van Kerkwijk, Kulkarni et al. in their 1995ApJ...444L..33V paper
A luminous companion to NAME Sgr 1806-20. It is a candidate to the
most massive star known (M(init) about 200 solar masses, and a luminosity
estimated to $10^6$ solar).
The relation between the Soft-gamma Repeater SGR 1806-20 and the massive
star LBV 1806-20 is not clear (they seem to be 12" apart),
but both sources are associated to the giant HII complex W 31.
It seems that the very strong wind from LBV 1806-20 is powering
the nebula SNR 10.0-0.3, and that LBV 1806-20 and
SGR 1806-20
are two members of the cluster [BDB2003] G010.00-00.24.
An interesting map of the region is presented as Fig.1 of the summary paper by
Corbel and Eikenberry (2004A&A...419..191C)
Annotations :
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