Kappa Draconis

Kappa Draconis is a blue giant star located in the constellation Draco. Its rarely used traditional name Ketu, meaning the Dragon's Tail, refers to the south lunar node according to the Vedic/Hindu lunar cycle.

At an apparent magnitude of 3.88, it is barely visible to the naked eye when artificial lighting from cities is present. Nevertheless, it is a powerful star, approximately five time as massive as the Sun. It is approximately 490 light-years away, and is 1,400 times brighter than the Sun.

Kappa is thought to be just entering its red giant phase, having exhausted the supply of hydrogen in its core. Over the next several thousand years, the star will expand, becoming more powerful but with a much cooler surface temperature. Tens of thousands of years from now, Kappa Draconis will appear much brighter, likely shining with a reddish hue.

The star is currently located at declination 69° 47' 18" North (RA 12h 33m 29.0s) , but due to the effects of precession, Kappa Draconis was the nearest star to the North Celestial Pole visible to the naked eye from 1793 BC to approximately 1000 BC. However, because it is so much dimmer than nearby Kochab, Kochab was considered the pole star during that time instead.

References

* < [http://www.astro.uiuc.edu/~kaler/sow/kappadra.html] by Jim Kaler
* < [http://www.alcyone.de/SIT/bsc/] click on Draco
* < [http://www.alcyone.de/cgi-bin/search.pl?object=HR4787] Alcyone (Yale Bright Star Catalogue)