Alpha Centauri Bb (α Cen B b) was a proposed exoplanet orbiting the K-type main-sequence star Alpha Centauri B, located 4.37 light-years from Earth in the southern constellation of Centaurus, but there has not been enough evidence to support the claim.. The claimed discovery of the planet was announced in October 2012 by a team of European observers, and the finding received …

Alpha / ˈ æ l f ə / (uppercase Α, lowercase α; Ancient Greek: ἄλφα, álpha, or Greek: άλφα, romanized: álfa) is the first letter of the Greek alphabet.In the system of Greek numerals, it has a value of one.Alpha is derived from the Phoenician letter aleph, which is the West Semitic word for "ox". Letters that arose from alpha include the Latin letter A and the Cyrillic letter А