LV426 like LV223 are the largest planetary bodies around separate gas giants in the binary star system known as 'Zeta Reticuli' comprising of Zeta Reticuli and Zeta 2 Reticuli. LV426 is the nearest planetary body to a gas giant and LV223 is the second nearest around the star Zeta 2 Reticuli.
Zeta Reticuli is the Bayer designation for a wide binary star system in the southern constellation of Reticulum 39.17 light years from Earth.
A binary star is a star system consisting of two stars orbiting around their common center of mass. The brighter star is called the primary and the other is its companion star or secondary.
LV426 is named 'Acheron' in an early draft of the script Alien. Notably Fiorina 'Fury' 161 was called 'Aceron' in an early draft for Alien 3.
As of 2010 it is understood that the stars are only orbited by a circumstellar debris disk.
Although LV426 and LV223 are around separate Gas Giants with about 1/7 of the diameter, LV426 is quoted as having a diameter of 1200kms (LV426 in an early Alien script was quoted as having a diameter of 120km) this would make the Gas Giant have a diameter of 8400kms, making it much smaller then Earth (12700kms), the same can be suggested for LV223.
Weyland astronomers discover multiple moons and a ringed planet just outside the Zeta 2 Reticula System, which are possibly able to support life. Weyland expects to travel there within the century.