9 Boötis [SEP] constellation
9 Boötis
9 Boötis is a single, variable star in the northern constellation of Boötes, located around 630 light years away from the Sun. It is visible to the naked eye as a faint, orange-hued star with a baseline apparent visual magnitude of 5.02. This object is moving closer to the Earth with a heliocentric radial velocity of −41 km/s.
This is an aging giant star with a stellar classification of K3 III, which indicates it has exhausted the hydrogen at its core and
Quadrans Muralis" and shrank the constellation a little in his 1801 "Uranographia" star atlas, to avoid it clashing with neighboring constellations.
In 1922, Quadrans Muralis was omitted when the International Astronomical Union (IAU) formalised its list of officially recognized constellations.
Notable features.
- The variable star BP Boötis was a member of the constellation.
- 39 Boötis is a double star that was transferred by Lalande into Quadrans.
- The Quadrantid meteor shower is still named after the obsolete constellation.