When is the best time to observe Zeta Scorpii?

Zeta Scorpii is best observed from April through June, with peak visibility during May when it transits around midnight in the Northern Hemisphere.

Where is Zeta Scorpii located in the sky?

Zeta Scorpii lies in the constellation Scorpius at right ascension 16h 55m and declination -42° 22′.

What telescope do I need to see Zeta Scorpii?

At magnitude 3.6, Zeta Scorpii is visible to the naked eye from dark skies, easy in any binoculars.

Zeta Scorpii — Star in Scorpius

HIP 82729; Zeta2 Scorpii

Magnitude 3.6^m Star Scorpius (Sco) Visible

Star Map + List + Plan

About Zeta Sco

Description

Zeta Scorpii (Zeta-2) is a K-type giant of spectral class K3 III about 132 light-years away. It shines at magnitude 3.62 and appears in a classic optical pair with the far-more-luminous Zeta-1 Scorpii — one of the most extreme optical doubles in the sky. Zeta-1, a 7,000-light-year distant hypergiant, lies only 7 arcminutes from Zeta-2. The two stars appear side by side but are physically unrelated.

Observing Tips

The Zeta-1/Zeta-2 pair is an excellent wide binocular double in Scorpius. Both stars are visible with the naked eye, and binoculars clearly reveal their subtle color difference: Zeta-1 bluish-white, Zeta-2 yellow-orange. Zeta Sco lies near the tail of Scorpius, close to the open cluster NGC 6231 ("The Prawn Cluster's cousin"). Best observed May through September.

History

The Zeta pair has been recognized since antiquity but never given a single Arabic or Greek name; the individual stars are simply labeled by Bayer.

Fun Facts

Zeta-1 Scorpii is one of the intrinsically brightest stars in the Milky Way — a hypergiant shining at around 1 million Suns. It lies embedded in the open cluster NGC 6231, which itself is part of the massive Scorpius OB1 association. The apparent nearness of Zeta-2 is entirely coincidental.