Alpha Ophiuchi
Encyclopedia
Alpha Ophiuchi is the brightest star
in the constellation
Ophiuchus
. It has the traditional name Ras Alhague, often condensed to Rasalhague.
Ras Alhague has an apparent magnitude
of +2.08, belongs to the spectral classification A5, and is about 47 light years distant from Earth.
The name Ras Alhague is from the Arabic
رأس الحواء (raʾs al-ḥawwἄ), meaning "the Head of the Serpent collector".
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
Ophiuchus
Ophiuchus
Ophiuchus is a large constellation located around the celestial equator. Its name is from the Greek "serpent-bearer", and it is commonly represented as a man grasping the snake that is represented by the constellation Serpens. Ophiuchus was one of the 48 constellations listed by the 2nd-century...
. It has the traditional name Ras Alhague, often condensed to Rasalhague.
Ras Alhague has an apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
of +2.08, belongs to the spectral classification A5, and is about 47 light years distant from Earth.
The name Ras Alhague is from the Arabic
Arabic language
Arabic is a name applied to the descendants of the Classical Arabic language of the 6th century AD, used most prominently in the Quran, the Islamic Holy Book...
رأس الحواء (raʾs al-ḥawwἄ), meaning "the Head of the Serpent collector".