When is the best time to observe Gienah Ghurab?

Gienah Ghurab is best observed from February through April, with peak visibility during March when it transits around midnight in the Northern Hemisphere.

Where is Gienah Ghurab located in the sky?

Gienah Ghurab lies in the constellation Corvus at right ascension 12h 16m and declination -17° 33′.

What telescope do I need to split Gienah Ghurab?

Splitting Gienah Ghurab requires an aperture beyond typical amateur scopes — even 500 mm struggles against the primary's glare — the components are separated by about 1.1″ at magnitudes near 2.6. The companion is about 7.1 magnitudes fainter, so glare from the primary — not separation — sets the minimum aperture. Larger apertures and steady seeing help resolve the pair cleanly.

Gienah Ghurab — Double Star in Corvus

HIP 59803; Gamma Corvi; 4 Corvi

Magnitude 2.6^m DoubleStar Corvus (Crv) Visible

Star Map + List + Plan

About Gienah Ghurab

Description

Gienah (Gamma Corvi) is a blue-white giant of spectral type B8IIIpHgMn at magnitude 2.59, the brightest star in Corvus. Located about 165 light-years from Earth, it is a chemically peculiar mercury-manganese star, similar to Alpheratz. Its luminosity is roughly 355 times solar.

Observing Tips

Gienah is the brightest of the four stars forming the distinctive trapezoid of Corvus, located at its upper-right corner. The constellation is easy to spot as a small sail-shaped figure south of Virgo. Despite being Gamma, it is the brightest star in the constellation. Best observed March through June.

History

The name Gienah comes from the Arabic 'janah al-ghurab,' meaning 'the wing of the crow.' This name is confusingly shared with Epsilon Cygni. Gienah Corvi is sometimes used to disambiguate. Corvus has been recognized as a small, distinct constellation since Babylonian times.

Fun Facts

Gienah Corvi is a mercury-manganese star — rare elements are concentrated in its atmosphere by atomic diffusion. These stars have patchy surface compositions, with islands of concentrated mercury and manganese creating spectral signatures unlike normal stars.