HD 168625 information

HD 168625
	; HD 168625 is the left star of the pair below the Omega Nebula. The other is the hypergiant HD 168607.
Observation data; Epoch J2000 Equinox J2000
Constellation	Sagittarius
Right ascension	18h 21m 19.548s
Declination	−16° 22′ 16.0572″
Apparent magnitude (V)	8.30–8.41
Characteristics
Spectral type	B6Ia+ (B2—B8) May be B60 due to hypergiant designation
U−B color index	+0.37
B−V color index	+1.41
J−K color index	0.599
Variable type	α Cygni
Astrometry
Radial velocity (Rv)	−4.00 km/s
Proper motion (μ)	RA: −0.71±1.20 mas/yr ; Dec.: +0.01±0.74 mas/yr
Parallax (π)	0.6212 ± 0.0640 mas
Distance	approx. 5,300 ly ; (approx. 1,600 pc)
Absolute magnitude (MV)	−8.39
Details
Radius	105 R☉
Luminosity	380,000 L☉
Surface gravity (log g)	1.74 cgs
Temperature	14,000 K
Rotational velocity (v sin i)	60 km/s
Other designations
	V4030 Sgr, HD 168625, BD −16°4830, SAO 161375, HIP 89963, AAVSO 1815-168
Database references
SIMBAD	data

HD 168625 (V4030 Sagittarii) is a blue hypergiant star and candidate luminous blue variable located in the constellation of Sagittarius easy to see with amateur telescopes. It forms a visual pair with the also blue hypergiant (and luminous blue variable) HD 168607 and is located to the south-east of M17, the Omega Nebula.

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^ ^a ^b Cite error: The named reference ducati was invoked but never defined (see the help page).
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[hipparcos-1] Cite error: The named reference hipparcos was invoked but never defined (see the help page).

[gcvs-2] Cite error: The named reference gcvs was invoked but never defined (see the help page).

[chentsov-3] Cite error: The named reference chentsov was invoked but never defined (see the help page).

[mahy-4] Cite error: The named reference mahy was invoked but never defined (see the help page).

[ducati-5] Cite error: The named reference ducati was invoked but never defined (see the help page).

[sterken-6] Cite error: The named reference sterken was invoked but never defined (see the help page).

[KharchenkoScholz2007-7] Cite error: The named reference KharchenkoScholz2007 was invoked but never defined (see the help page).

[dr2-8] Cite error: The named reference dr2 was invoked but never defined (see the help page).

Observation data Epoch J2000 Equinox J2000
HD 168625 is the left star of the pair below the Omega Nebula. The other is the hypergiant HD 168607.
Constellation	Sagittarius
Right ascension	18^h 21^m 19.548^s^[1]
Declination	−16° 22′ 16.0572″^[1]
Apparent magnitude (V)	8.30–8.41^[2]
Characteristics
Spectral type	B6Ia⁺^[3] (B2—B8^[4]) May be B60 due to hypergiant designation
U−B color index	+0.37^[5]
B−V color index	+1.41^[5]
J−K color index	0.599
Variable type	α Cygni^[6]
Astrometry

Radial velocity (R_v)	−4.00^[7] km/s
Proper motion (μ)	RA: −0.71±1.20^[1] mas/yr Dec.: +0.01±0.74^[1] mas/yr
Parallax (π)	0.6212 ± 0.0640 mas^[8]
Distance	approx. 5,300 ly (approx. 1,600 pc)
Absolute magnitude (M_V)	−8.39^[4]

Details^[4]

Radius	105 `R`_☉
Luminosity	380,000 `L`_☉
Surface gravity (log g)	1.74 cgs
Temperature	14,000 K
Rotational velocity (v sin i)	60 km/s

Other designations
V4030 Sgr, HD 168625, BD −16°4830, SAO 161375, HIP 89963, AAVSO 1815-168
Database references
SIMBAD	data

HD 168625 information

and 7 Related for: HD 168625 information

HD 168625

HD 168607

Hypergiant

Omega Nebula

List of supernova candidates

Luminous blue variable

MN18