- 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 temperature is about 8,300 degrees Celsius.
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.