---
name: Ras Algethi (α Her)
constellation: Her
created_by: 8mag
created_date: 2022-01-21 17:00:00
updated_by: skybber
updated_date: 2022-02-07 15:21:30.994975
---
a bright red star almost on the border with Ophiuchus, a giant whose brightness varies irregularly between 3.1mag and 3.9mag, but often only between 3.3mag and 3.7mag. The period is 90 to 100 days. Suitable comparison stars are ι and κ Ophiuchi, which lie about 6.5 degrees to the southwest and have brightnesses of 4.3mag and 3.2mag, respectively. Alpha Herculis is also a binary whose second fifth-magnitude component, 4.7" away, is visible even in small telescopes with a 6 cm diameter objective. It has a greenish tint that contrasts nicely with the red giant.