Blue-white main-sequence star · Sagittarius

Nunki

Also known as: σ Sagittarii (σ Sgr), HIP 92855

mag 2.1230 light-years

About

Nunki (σ Sagittarii) is a blue-white main-sequence star of magnitude 2.1 in Sagittarius, about 230 light-years away.

Nunki is in the constellation Sagittarius.
Best evenings: around mid-August it is highest at about 9 pm (10 pm in summer time); a month earlier, two hours later.
Where on Earth: it is seen well, at least 10° up, from south of 54° N.
Star patterns: Teapot.

When it rises and sets tonight, how high it climbs and how much the Moon gets in the way are worked out in your browser for your place.

EyesEasy, even from town. It looks blue-white.
Binoculars (10×50)A sharp point; binoculars bring out its colour and the fainter stars around it.
Telescope (6–8 inch)Still a point of light at any magnification — stars are too far away to show a disc. Low in the sky, bright stars twinkle and flash colours.

Stars look the same in any instrument: brighter and sharper, but never bigger.

Proper name	Nunki
Designation	σ Sagittarii (σ Sgr)
Hipparcos number	HIP 92855
Type	Blue-white main-sequence star
Spectral type	B2.5V
Colour	Blue-whiteB−V colour index −0.13
Magnitude	2.1The smaller the number, the brighter.
Distance	230 light-yearsThe light you see left it around 1800.
Proper motion	0.054″ per year across the sky
Constellation	Sagittarius
Right ascension (J2000)	18h 55m 15.9s
Declination (J2000)	−26° 17′ 48″