"Mother? I've turned the cooling unit back on. Mother?!"
"The ship will automatically destruct in T-minus 5 minutes."
"You bitch!"
Mother and Ripley (from Alien)

MU/TH/UR 6000,[3] commonly referred to simply as "Mother", was a model 282 artificial intelligence[2] computer mainframe used aboard vessels such as the Weyland-Yutani Corporation's Model CY78.3 Affiance-class U extended range colony ship and Lock-Mart Industries' CM-88B Bison freighter. Mother operated many of the ship's background systems, and auto-piloted the vessel while the crew were in hypersleep. It was also programmed to wake the crew during the voyage should certain situations arise.[1] It was eventually supplanted by the MU/TH/UR 9000.


Mother was a 2.1 terabyte artificially intelligent mainframe that monitored all of the Nostromo's automated flight and environmental functions.[2] The computer core was located in a secure room on the Nostromo's upper deck, only accessible to the ranking officer aboard, normally Captain Arthur Dallas.[1] However, Mother could communicate with the entire crew through the ship's intercom system, without them having to enter her room directly.


Years before the Nostromo's final voyage, the USCSS Covenant, a Weyland-Yutani colony spacecraft was known to use an artficial intelligence mainframe called MU-TH-UR, possibly an earlier version of the MU-TH-UR 6000.

Aboard the Nostromo, Mother worked with the ship's science officer, Ash, to implement Special Order 937 and ensure the survival of the Xenomorph specimen collected from LV-426. Mother also monitored the activities of the crew of the Nostromo for Weyland-Yutani. While it never explicitly took action to harm the crew, it was complicit in the preservation of the Alien.

Nostromo explosion

The Nostromo exploding.

Mother was destroyed when the Nostromo was blown up by Ripley in an attempt to kill the Xenomorph loose on board.





  1. 1.0 1.1 1.2 Dan O'Bannon, Ronald Shusett (writers), Ridley Scott (director). Alien (1979), 20th Century Fox [DVD].
  2. 2.0 2.1 2.2 Lee Brimmicombe-Wood. Aliens: Colonial Marines Technical Manual, p. 135 (2012), Titan Books.
  3. In the script and film the computer is referred to by the crew members as "Mother". An October 1979 issue of Fantastic Films magazine, as well as the back of the 1980 Fox videodisk of the film, explain that "Mother" is an abbreviation for "MU/TH/UR 6000", the model of the computer. The chapter list for Alien in the 2003 Alien Quadrilogy DVD set also lists it as "MU/TH/UR".
  4. 4.0 4.1 http://www.remington-rand.com/alien/