A red giant star in the constellation of Hercules, Ras Algethi is also called, more properly, Alpha Herculis. Ras Algethi is arabic for “the Kneeler’s Head.” A picture of the constellation can be found here. From this site:
«The leading star alpha Her, called Ras Algethi (arab.: kneeler’s head), is a red supergiant (spectraltype M5Ib-II). Its brightness varies erratically from 3.1 mag to 3.9 mag. A small telescope reveals a second star of 5.39 mag (physically not related to the other). This ‘companion’ is a binary consisting of a G5 giant and a F2 main sequencec star (not resolvable by amateur scopes). The brightness of the variable star S Her varies every 307 days from 5.9 mag to 13.6 mag. It belongs to the same class of variable stars as R Ser. The varibale star SZ Her is a eclipsing binary. Every 16 hour the fainter component dims the brighter from 10.2 mag down to 12th mag. The eclipse has a duration of about 90-100 minutes. Tom Polakis observed this star and printed a lightcurve.»
«Though the brightest of its stars is only middling second magnitude, the constellation as a whole is fairly prominent. Rather oddly, Rasalgethi, the Alpha star, is the fifth brightest, perhaps because it is a bit south of the main constellation pattern. The name means “the Kneeler’s Head, in reference to an early name for the constellation, the figure of the man seen upside down, his head toward the south. Though of the third magnitude as seen from Earth, the star itself is magnificent, a reddish giant or even supergiant with a surface temperature of about 3000 degrees Kelvin. At a distance of about 400 light years, Rasalgethi to the human eye is almost 500 times more luminous than the Sun»
There are several small, rocky planets between the orbits of Ras Algethi and its binary neighbor. Technically, these worlds orbit the binary pair, but Ras Alegthi is hard to miss in their skies.
In the Earth year 3001, a colonizing expedition was sent to one of this rocky worlds, which proved rich in mineral resources. A mining operation was established, but transporting this bounty back to earth became unpractical.
- Ras Algethi