- Stars with a name
- Rasalhague
Rasalhague
α Ophiuchi
Rasalhague is a white giant, in the constellation Ophiuchus. The light you see from it tonight left it around 1977.
Where to find it
From mid-northern latitudes, such as New York, Rome or Tokyo, it is best seen in the evening sky in May, June, July, August, and September.
Bright enough to see even from a city. Apparent magnitude 2.08.
What it’s like
It gives off 28 times as much light as the Sun.
Its surface is at about 8,500 degrees.
It is 48.6 light years away: 460 trillion kilometres.
It is the star of people born around 1977: the light that left it then is reaching Earth now.