P Eridani


p Eridani is a binary star system in the constellation of Eridanus whose distance from the Sun is approximately 26 light-years based upon parallax. It was found to be a double star in December 1825 by James Dunlop in Australia at his home at Paramatta, now spelt Parramatta. It is visible to the naked eye as a dim, orange-hued star. The system is moving further from the Earth with a heliocentric radial velocity of +23 km/s.
This system consists of a pair of K-type main-sequence stars with stellar classifications of K2V Component A has visual magnitude 5.87, while component B is magnitude 5.76. They orbit each other with a period of 475.2 years, an eccentricity of 0.53, and a semimajor axis of.

Naming

The name "p Eridani", according to Nature, p. 589 has been:
"... occasionally miscalled 6 Eridani, which would imply that it was one of Flamsteed's stars. Flamsteed, it is true has a star which he calls 6 Eridani. The designated letter 'p' was attached to a star by Lacaille in the catalogue at the end of his Coelum Australe Stelliferum. The number '6' is merely borrowed from Bode."
The use of Bode numbers was commonly used in the early 19th century, but this antiquated system has now fallen into disuse for more than a century.