|In story information|
Colu is a fictional planet in DC Comics whose primary inhabitants are called the Coluans. Another name given for the planet was "Yod" (Hebrew for Iodine, like many other planets in the DC universe, it is named after a chemical element), which has appeared only once in comics, was later pointed out in a letter by a fan.[volume & issue needed] According to the reply to the letter, "Yod" is the Coluan name for their homeworld, however this name has not appeared since.[volume & issue needed]
Planetary Information 
20th century Colu is a rim world found on the approach to the Magellanic Clouds. It is the only inhabitable planet of its solar system and is the fourth planet from its sun. The surface is split between 50% land and water, and while it has polar ice caps and a few deserts, is mostly temperate. The majority of its populace lives in large cities with less than 1% of its population residing elsewhere outside those cities.
In Pre-Zero Hour continuity, Colu's capital was given as Metaire and was the most advanced city in the galaxy, in which the shrine of enlightenment was built. In Mark Waid's Legion reboot, Colu uses its shrinking technology (pioneered by the original Brainiac) to make maximum use of its surface area. It is sometimes known as the "Bottle Planet of Colu".
The Coluan race is essentially a green-skinned humanoid race. The average member of the Coluan race is noted for having a "Eighth level" intelligence (far higher than humans), with the notable exception of the Dox family who have a "Twelfth level" intelligence due to genetic mutation. They also have exceptionally long lifespans lasting for centuries (approximately 500 years), which Brainiac 5 confirmed was a product of genetic manipulation. In the 30th century setting of the Legion of Super-Heroes, Colu is famous for the incredible intellects of its inhabitants. The most brilliant, but most erratic, are still considered to be the Dox family, which includes the Legion's own Brainiac 5 (a.k.a. Querl Dox). Before the Computer Tyrants took over, the planet was ruled by its greatest intellect.
After the Zero Hour reboot, it was revealed that most Coluans prefer purely theoretical research, and found Brainiac 5's interest in experimentation disturbing. It was later revealed that, following their experience with the Computer Tyrants, the Coluans had a prejudice against artificial life. They also came to the conclusion that the Twelfth level intelligence is mentally and socially unstable and that their own Eighth level is the perfect intelligence level needed to function without these problems.[volume & issue needed] However, the same Coluan who mentioned the information later proved that the truth was exactly opposite of this statement in the outcome of the war against Robotica and C.O.M.P.U.T.O..[volume & issue needed]
List of residents or characters who originate from this world include:
- Brainiac 417 (853rd century)
- Brainiac 13 (64th century)
- Brainiac 8 (Indigo)
- Brainiac 6 (32nd century)
- Brainiac 5 (Querl Dox, 31st century)
- Brainiac 4 (Kajz Dox, 30th century)
- Brainiac 3 (Lyrl Dox, 21st century)
- Brainiac 2 (Vril Dox II, 20th century)
- Brainiac (Vril Dox, 20th century)
- Pulsar Stargrave
In the pre-Crisis DC Universe of Earth-One, the Tyrants sent the android Brainiac into space to find suitable targets. To perpetrate the illusion that Brainiac was Coluan, a young Coluan named Vril Dox was sent along and instructed to pose as Brainiac's "son". Dox rebelled against the tyrants and freed Colu. He was the ancestor of Brainiac 5 of the Legion of Super-Heroes.
Post Crisis 
In the Post-Crisis DC Universe, Colu was still ruled by the Computer Tyrants. To remain in control of Colu, the Tyrants would resort to measures such as memory erasing and brainwashing Coluan children so that the populace knew no other lifestyle than the one the Tyrants offered.
However, in this timeline they did not create a Brainiac android. Instead they created Brainiac inadvertently when they sentenced the rebellious scientist Vril Dox to death, and his consciousness somehow found its way to Earth. His cloned lab assistant, Vril Dox II, eventually overthrew the Computer Tyrants, with the aid of the various heroic aliens who became L.E.G.I.O.N.. The Computer Tyrants downloaded themselves into a robot body, (apparently going on to become Pulsar Stargrave) but was unable to take Colu back from Vril Dox II.
Brainiac subsequently returned to Colu and attempted to conquer it using Brainiac 5 and the "sleepnet" (which was due to be invented on Colu in 750 years time). Vril Dox II returned to Colu to stop his father from conquering it and after a struggle, he and Brainiac 5 managed to defeat Brainiac. Afterwards, the Coluan high council decided that the Dox family was barred from ever returning to Colu (which at some point would be overturned). They also declared that they would only research scientific theory rather than experimentation. Brainiac 5 revealed afterwards that Colu was exactly the same in the 21st century as in the 31st century - Colu would see no significant development in the next 1,000 years.
Legionaires 1,000,000 
In the Legionaires #1,000,000 one-shot, which showed a possible future for Colu, Colu was said to have joined itself with Bgztl (the homeworld of Phantom Girl). Over time, the two worlds' inhabitants slowly merged powers to form a race of people who, not only had great intelligence, but became spirit intellects, lacking the distraction of flesh. The two joint worlds were Brainiac 417's homeworlds.
Other media 
Colu has been mentioned in the Legion of Super-Heroes animated series, and later shown in the series finale "Dark Victory." In the series, the Coluans are not organic but a race of highly advanced cybernetic beings that function as a "hive mind" collective, from which Brainiac 5 has separated to become an individual.
- L.E.G.I.O.N. #1 (February 1989)
- Legionnaires #8 (November 1993)
- Beatty, Scott (2008), "Brainiac 5", in Dougall, Alastair, The DC Comics Encyclopedia, London: Dorling Kindersley, p. 60, ISBN 0-7566-4119-5
- The Legion #10-15
- Legionaires 1,000,000
- Legion of Super-Heroes in the 31st Century #4