White giant · Eridanus

Acamar

Also known as: θ¹ Eridani (θ¹ Eri), HIP 13847

mag 2.9160 light-years

About

Acamar (θ¹ Eridani) is a white giant of magnitude 2.9 in Eridanus, about 160 light-years away.

Acamar is in the constellation Eridanus.
Best evenings: around late December 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 40° N.

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.
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	Acamar
Designation	θ¹ Eridani (θ¹ Eri)
Hipparcos number	HIP 13847
Type	White giant
Spectral type	A4III+
Colour	WhiteB−V colour index 0.13
Magnitude	2.9The smaller the number, the brighter.
Distance	160 light-yearsThe light you see left it around 1870.
Proper motion	0.059″ per year across the sky
Constellation	Eridanus
Right ascension (J2000)	02h 58m 15.7s
Declination (J2000)	−40° 18′ 17″

Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →