(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 Other object types:
Pl (), Pl? (TOI,XO), * (BD)
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''; as well as Tycho2, UCAC4, and Gaia DR2/3 without proper motions
B : 0.01-0.1''; as well as Tycho2 and UCAC4 with proper motions
A : Hipparcos and Gaia DR2/3 with proper motions; sometimes VLBI
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''; as well as Tycho2, UCAC4, and Gaia DR2/3 without proper motions
B : 0.01-0.1''; as well as Tycho2 and UCAC4 with proper motions
A : Hipparcos and Gaia DR2/3 with proper motions; sometimes VLBI
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''; as well as Tycho2, UCAC4, and Gaia DR2/3 without proper motions
B : 0.01-0.1''; as well as Tycho2 and UCAC4 with proper motions
A : Hipparcos and Gaia DR2/3 with proper motions; sometimes VLBI
Syntax of proper motions is : "pm-ra pm-dec [error ellipse] quality bibcode"
pm-ra : mu-ra*cos(dec) (expressed in the ICRS system in mas/yr)
pm-dec : mu-dec (expressed in the ICRS system in mas/yr)
[error ellipse] : error major axis and minor axis (in mas), orientation angle (in deg)
quality : flag of quality (A=best quality →E=worst quality, ∼ =unknown quality)
bibcode : bibcode of the proper motion reference
Proper motions mas/yr :
-17.349 14.780 [0.012 0.015 90] A 2020yCat.1350....0G
Syntax of parallax is : 'value quality [error] bibcode'
value : parallax value
quality : flag of quality (A=best quality →E=worst quality, ∼ =unknown quality)
[error] : mean error
bibcode : bibcode of the parallax reference
Parallaxes (mas):
6.1489 [0.0136] A 2020yCat.1350....0G
SIMBAD within arcmin
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Some important notes on this object about identifications and objects associations. notes:
Planet of XO 1 detected by McCullough et al. (astro-ph/0605414), see details about XO-1b in the Extrasolar Planets Encyclopaedia.
Hierarchy : number of linked objects whatever the membership probability is (see description here ) :
: 1
Display criteria : All >=90% stars galaxies radio IR <2 arcsec #ref>50
The link on the acronym of the identifiers give access to the information for this acronym in the dictionary of nomenclature. Identifiers (5) :
An access of full data is available using the icon Vizier near the identifier of the catalogue
BD+28 2507b
TOI-2021b
XO-1b
NAME-IAU Negoiu
TOI-2021.01
References (195 between 1850 and 2026) (Total 195) 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
Reference summaries :
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External archives :
Link by name to the catalogue in VizieR :
BD+28 2507b
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