Star profile

Arcturus

Alpha Boötis · Boötes

Nearby star

3D likeness based on its real data · class K · ~4,200 K

What is Arcturus

Arcturus burns with an ancient orange in the constellation of Boötes, only 36.7 light-years away —one of the closest orange giants to our Solar System. Its name, from the Greek «guardian of the bear», speaks of its endless pursuit of Ursa Major across the night sky. The light reaching the eye tonight set out when the first mobile phones fit in a pocket and no one spoke yet of social networks.

Where it is and when to see it

Arcturus lies in the northern celestial hemisphere. It is one of the brightest stars in the sky: visible even from a city. Its best month of the year is April, when it culminates around midnight.

From London it culminates about 58° above the horizon.
From New York it culminates about 68° above the horizon.
From Sydney it culminates about 37° above the horizon.

It can be seen from anywhere north of 71° S.

It is the brightest of the 88 stars of Boötes in our catalogue, which makes it the best starting point for finding your way around the constellation.

The light you see today left it about 37 years ago.

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Astronomical data for Arcturus

Constellation: Boötes
Apparent magnitude: -0.05
Distance: 36.7 light years
Coordinates (J2000): RA 213.915° · Dec 19.182°
Catalogue: HIP 69673 · HD 124897

A symbolic commemorative gift: neither the signature nor the chosen name implies ownership of the star or recognition by the IAU.

Other stars in Boötes

Boötes has 88 stars in Stelvia's catalogue. Here are a few of them.

See all 88 stars in Boötes