2001: A Space Odyssey Wiki
2001: A Space Odyssey Wiki

The Jovian Monolith, better known as Jupiter Monolith (also Star Gate monolith; Big Brother;[1][2] and designated TMA-2), is a larger monolith that was found in the Jovian system in Arthur C. Clarke’s 2001: A Space Odyssey and its film adaption.

Project Jupiter[]

In the 2001 novel, Discovery's original mission parameters were to explore Jupiter. But in 1999, its mission objective changed. The HAL 9000 onboard supercomputer, was directed to go the Saturn system[3] to investigate an anomalous radio energy signal—targeted precisely at Saturn. Bowman later determines that the anomalous signal that triggered the re-direct, was pointed at one of Saturn’s moons, Iapetus, where a monolith (designated TMA-2), sat upright on the moon just like that of the TMA-1 discovered in 1999, in the Tycho crater of Earth's moon. In the film adaption,[note 1] once the Discovery arrives to the Jovian system, the mission objective (TMA-2) suddenly appears in space, in the proximity of Jupiter's moon Io.[note 2]

TMA-2 designation[]

The Jovian Monolith, found in the Jovian system, is designated TMA-2, a misnomer (as pointed out by Bowman), as the T stands for Tycho, a crater on Earth's moon, distinct from TMA-1. A notible difference are their sizes, though they share the same 1:4:9 dimensions. The Jovian Monolith is much larger in size, and had been nicknamed "Big Brother" by Heywood Floyd, a reference to Dave Bowman who described the monolith as TMA-1's "big brother" when he first encountered it. The Russian crew of the Cosmonaut Alexei Leonov referred to the Jovian monolith as Zagadka, the Russian word for "enigma".

Star Gate[]

Star Gate

"Oh My God!-it's full of stars!"

The Jovian monolith was a "Star Gate" created and used by The Firstborn, who conducted experiments throughout many star systems more than 4 million years ago. The TMA-2 Star Gate served as a type of wormhole, until it merged with Jupiter to become a mini-sun. David Bowman traveled through this Star Gate, as portrayed in the finale of the 2001 novel and film, where it takes him to the "Hotel Room".

The novels have more to say on the Star Gate. In 2001, we are told by the narrator that TMA-2 (inside of which was the Star Gate) was indeed placed around the same time as the placing of TMA-1, on one of Saturn's moons Iapetus. The narrator then goes on to say that another moon of Saturn's was destroyed in order to produce the Star Gate. While the actual purpose of it is not made clear, it is suggested that it is an interstellar highway, which various ships use as a means of travel, as well as an automatic trap set to capture David Bowman.

Becoming Lucifer[]

In 2010, the Jovian monolith multiplies into thousands of monoliths. Being a Star Gate, perhaps it enabled many monoliths to port to the Jupiter system, from otherworldly places. They in turn caused Jupiter to become a mini-sun, termed Lucifer.


  1. In the 2001 novel, the climax of the story was set on Saturn; however the film version relied on Jupiter, as the SFX specialist could not produce a convincing model of Saturn's rings, thus the monolith is repositioned—floating in space between Io and Jupiter.
  2. The monolith signal originally detected at Saturn's Iapetus in the novel, and then suddenly appearing at Jupiter’s Io in the film—fits rather well in the mythology of the space odyssey monoliths: appearing where they want, when they want, and multiplying themselves at any given time.