|Film:||2001: A Space Odyssey|
|Location:||Clavius Base, Earth's moon|
|Known relatives:||Diana Halvorsen (daughter)|
Ralph Halvorsen was a secondary character featured in the Space Odyssey mythos as envisioned by author Arthur C. Clarke. Played by actor Robert Beatty, he first appeared in the 1968 Stanley Kubrick film 2001: A Space Odyssey. The character also appeared in Clarke's 2001: A Space Odyssey novel, which was published to coincide with the release of the film.
Ralph Halvorsen was the administrator of the Southern Province of Earth's moon and worked alongside notable scientists such as Bill Michaels and Heywood R. Floyd. He was stationed at Clavius Base in the Clavius Crater. Ralph's young daughter, Diana Halvorsen, was born at Clavius in 1996, making her one of the first Earthlings born off-planet. In the year 2000, Halvorsen headed up a research project analyzing a bizarre, extraterrestrial artifact found in Tycho Crater. Due to the magnetic resonance given off by the Monolith, the slab of stone was codified TMA-1 (Tycho Magnetic Anomaly number one).
Halvorsen introduced Doctor Floyd to a panel of experts and listened as Floyd told them about the cover story that had been employed to keep the population of Earth in the dark about their discovery. Afterward, Halvorsen accompanied Floyd as well as geophysicist Doctor Roy Michaels to the site of TMA-1. Halvorsen despised lunar transport and refused to exit the Moonbus after they arrived at the site. 
Diana Halvorsen was born the daughter of lunar administrator Ralph Halvorsen at Clavius Base on Earth's moon in the year 1996. Living in a low-gravity lunar environment had an affect on Diana's growth cycle. By the time she was four-years-old, she physically resembled a girl of eight. In the year 2000, Ralph introduced Diana to a colleague of his, Doctor Heywood R. Floyd. 
Diana Halvorsen likely passed away at some point during the thousand-year Space Odyssey saga, but such information is conjectural and was never established in the source material.
Notes & Trivia
- The character of Ralph Halvorsen was created by director Stanley Kubrick and author Arthur C. Clarke.
- 2001: A Space Odyssey
- 2001: A Space Odyssey images
- 2001: A Space Odyssey characters
- 2001: A Space Odyssey miscellaneous