Constellation Corvus and Delta Corvi

Last week, I went out on a nominally clear night to see if I could find the Virgo Cluster of galaxies. I could not. But there was a very apparent quadrilateral in the south. So, I targeted that. I found delta Corvi, an interesting binary.

Wikicommons from Sky & Telescope

“Delta Corvi has more than 2.7 times the mass of the Sun, which is causing it to radiate a much higher energy output—roughly 69 times the Sun's luminosity. … Hence it is either a subgiant star around 260 million years old …  or a pre-main sequence star around 3.2 million years old that has not completely condensed and settled on the main sequence.”

Its companion shares its radial velocity and those have not changed measurably since the pair was determined in 1823 by James South and John Herschel. They may be 

The angular separation is given as 24.2 arcseconds. (Wikipedia – Delta Corvi)

The constellation has been called the Crow or the Raven for at least 3,000 years. To the Babylonians, it heralded the autumnal rainy season. The Romans called it Corvus and the Arabs gave it the same name in their language.  

5 May 2021 2300 hrs CDT

 Moreover, delta Corvi was called al-ghuraab, rendered as “Algorab” on European charts, which means crow. Gamma was Gienah or “right wing.” Epsilon Corvi was minqar (Minkar on our modern charts), meaning “wing.” The named attached to Beta, Kraz, has never been traced adequately. 

 The USS Algorab was an Arcturus class attack transport in service from 1939 to 1945. The ship served in the Atlantic, the Caribbean, and the Pacific. For its action in the Pacific, it earned four battle stars.

 

As a petty officer in the Texas Maritime Regiment, my insignia were crows. I joined the service late in life and was placed in the command group to serve the general staff where I fit in well. However, there were a couple of times when my top sergeant had to counsel me to keep in mind that my crows were not eagles.

 

Previously on Necessary Facts

Binary Star Project 

Scorpio and the Precession of the Equinox 

Asterisms 

Astronomical Symbols on Ancient and Medieval Coins 

Why I Served