Star Trek: Who Are The Andorians & Why Are They Blue?

No matter which aspect of the franchise they're most familiar with, there's a good chance that "Star Trek" fans have crossed paths with the Andorians at least once or twice. These blue-hued aliens have been popping up in various shows and movies since "Star Trek: The Original Series," cementing their position as one of the most enduring alien races to feature in the franchise's universe. However, while many fans are familiar with the basics of the Andorians — including their homeworld of Andoria, their humanoid appearance and sentience, and their militaristic societal structure — some may still have a question about them: Why, exactly, are they blue?

Typical Andorians sport light-blue skin, white hair, and a small pair of antennae atop their heads. While the origin of their blue coloring hasn't been explicitly addressed within the official canon, "Star Trek: Enterprise" offers a potential explanation. In Season 4, Episode 13, titled "United," viewers see an Andorian bleed, revealing that the aliens have blue blood. The ostensible implication is that the Andorians' unique physiology allows the color of their blood to affect their skin pigmentation, giving them their trademark blue hue.

That provides fans with at least something of an explanation for why Andorians are blue in the "Star Trek" universe, but franchise devotees may also be curious about the original design conception behind the aliens and just why, exactly, the powers that be felt compelled to make them blue in the first place. There is an explanation on this front as well, though whether it's a satisfying one is up for debate.

The Andorians were originally created by script writer D. C. Fontana for "Star Trek: The Original Series," and their overall design was ultimately cemented by makeup artist Fred Phillips. Fontana introduced the aliens in Season 2, Episode 10, titled "Journey to Babel," but while she seemingly always intended for them to have blue skin, her reasoning is rather unclear. The original script for "Journey to Babel" includes a memo from Fontana  regarding the Andorians' makeup and costume design, and she makes particular note of their blue coloration. In the words of Fontana herself, "Andorians are pale blue. Because."

Fontana's memo suggests that she and the rest of the "Star Trek" team's motivation for making the Andorians blue was purely an aesthetic choice meant to distinguish the aliens and nothing more. Superficial reasoning or not, however, this particular design decision resulted in the creation of one of the most iconic "Star Trek" aliens of all time.