LV-426

LV-426 is a fictitious planetoid appearing in the films Alien (1979) and Aliens (1986). It has also been referred to as "LB-426."

Description
In the context of the films' plots, LV-426 is a natural satellite (or moon) in orbit around a gas giant called Calpamos, in the Zeta2 Reticuli system, 37 light years from Earth, lying beyond the "Outer Rim". LV-426 has 86% of Earth's gravity. In Alien the atmosphere consists mostly of nitrogen and methane, but by the events of Aliens the atmosphere has been altered due to terraforming by human colonists and is breathable.

Source materials differ widely on the diameter of the planetoid: A figure of 1,200 km is given in Alien, while the Aliens: Colonial Marines Technical Manual (a supplementary book to Aliens) gives a figure of 12,201 km. In Aliens LV-426 is described as "a rock" with no indigenous life. In Alan Dean Foster's novelization of "Alien", the travel time between LV-426 and Earth is given as ten months. In the novelization of the film "Aliens", also by Foster, the travel time is given as only three weeks.

Alien
In Alien the crew of the Nostromo lands on the planetoid (unnamed in this film) in response to a signal, which they discover is emanating from a mysterious derelict spacecraft on the surface. They find the remains of an unknown alien creature on the ship as well as a chamber filled with strange eggs. A creature emerges from one of the eggs and attaches to a crew member's face, implanting him with an Alien embryo which later kills most of the Nostromo's crew.

According to the book Giger's Alien, in an early version of the script the Alien eggs were to be housed in a separate architectural structure, shaped in the form of a massive pyramid.

Aliens
LV-426 is the primary setting of the sequel film Aliens (1986). In the film, during the fifty-seven years since the events of Alien the Weyland-Yutani Corporation has established a terraforming colony there, making it habitable with the aid of an enormous, fusion-powered atmosphere processor. The terraforming colony is named "Hadley's Hope." The colony is destroyed when the atmosphere processor suffers critical damage during the events of the film, causing a thermonuclear explosion.

The Hadley's Hope colony was designed by Ron Cobb from preliminary sketches by James Cameron. Cobb conceived that the colony would be broken down into three districts: a main complex, the "frontier town," and the atmosphere processing station, all surrounded by a storm wall. Partial full-size, 1/6, and 1/50 scale sets were built for various shots. Ron Cobb designed most of the colony with modules that could be added and rearranged as the population grew.

Aliens vs. Predator computer game
LV-426 also appears in the computer game Aliens versus Predator. In the game's story the derelict ship has survived the explosion that occurred in Aliens, and the Weyland-Yutani corporation has established a new colony, atmosphere processor, and research facility on the planetoid dedicated to studying the derelict ship and its contents. All of these are destroyed ten years later during another Alien infestation when an unnamed Colonial Marine disables the atmosphere processor's cooling systems, causing another explosion.