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Show the direction and distance to this object on the Galactic Map.

Proper Name	None
Bayer Designation	None
Flamsteed Number	4 Sagittarii
HR (BSC)	6700
HD	163955
Constellation	Sagittarius
Right Ascension	17h 59m 48s
Declination	-23° 48' 58"
Distance	408 light years 125 parsecs
Magnitude	Apparent: +4.74 Absolute: -0.76
Spectral Class	B9V blue main sequence star (some sources prefer A0)
Optimum Visibility	July
Notes	4 Sagittarii is notable for its rotation rate which, at an estimated 149 km/s, is more than seventy times that of the Sun. This rapid rotation means that the star shows a distinctly oblate shape, extending outward at its equator and flattening at its poles. There are indications that 4 Sagittarii is a binary star, though if so, its companion has yet to be directly detected.

Blue 4 Sagittarii against the backdrop of the Milky Way. The bright mass to the southeast is M8 or NGC 6523, commonly known as the Lagoon Nebula. Imagery provided by Aladin sky atlas

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