When is the best time to observe Etamin?

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

Where is Etamin located in the sky?

Etamin lies in the constellation Draco at right ascension 17h 57m and declination +51° 29′.

What telescope do I need to see Etamin?

At magnitude 2.2, Etamin is visible to the naked eye under most conditions.

Etamin — Star in Draco

HIP 87833; Gamma Draconis; 33 Draconis

Magnitude 2.2^m Star Draco (Dra) Visible

Star Map + List + Plan

About Etamin

Description

Eltanin (also spelled Etamin) is an orange giant of spectral type K5III at magnitude 2.23, the brightest star in Draco. Located about 154 light-years from Earth, it has a luminosity of roughly 471 times solar. Despite its Gamma designation, it is brighter than Alpha Draconis.

Observing Tips

Eltanin marks the head of Draco, forming part of a small quadrilateral with Beta, Xi, and Nu Draconis. It is visible year-round from mid-northern latitudes as part of the circumpolar constellation. Its orange color is apparent in binoculars. Look for the Dragon's head between Vega and the Keystone of Hercules. Best placed high overhead during summer evenings.

History

The name Eltanin comes from the Arabic 'al-tinnin,' meaning 'the great serpent.' In 1728, James Bradley attempted to measure the parallax of Eltanin and instead discovered the aberration of light — the apparent shift in star positions caused by Earth's orbital velocity. This was the first direct evidence that Earth orbits the Sun.

Fun Facts

Bradley's discovery of stellar aberration using Eltanin was one of the most important observations in the history of astronomy, providing the first observational proof of Earth's orbital motion. In about 1.5 million years, Eltanin will pass within 28 light-years of Earth and become the brightest star in the sky.