What is the significance of 42? Why Elon Musk is bringing it up with SpaceX’s Starship rocket

When Elon Musk revealed that SpaceX’s Starship is designed to operate with 42 engines, many of us initially assumed it was purely an engineering decision. After all, large rockets need immense thrust and redundancy, and 42 engines could simply be the result of rigorous design calculations. But a few noticed the symbolic weight of the number. The number 42 isn’t just a technical detail; it’s a playful nod to Douglas Adams’ iconic sci-fi series The Hitchhiker’s Guide to the Galaxy, where 42 is humorously presented as “the Answer to the Ultimate Question of Life, the Universe, and Everything.” Musk’s choice reflects his tendency to weave pop culture, philosophy, and engineering into a single narrative, blending ambition with humour while pushing humanity toward interplanetary travel.In Douglas Adams’ 1979 novel The Hitchhiker’s Guide to the Galaxy, a group of hyper-intelligent beings creates a supercomputer called Deep Thought to calculate the ultimate answer to the biggest question of all: What is the meaning of life, the universe, and everything? After running calculations for 7.5 million years, Deep Thought finally provides the answer: the number 42.But here’s the twist: Deep Thought admits it doesn’t actually know what the original Question was. It was never designed to calculate that. To find it, Deep Thought explains, a far greater computer is needed, one capable of working over 10 million years. That computer turns out to be Earth itself, created as part of a vast program to uncover the Ultimate Question.Unfortunately, Earth is destroyed by the Vogons just five minutes before the program’s completion. This means the Answer (42) survives, but the Question is lost forever. The result is both absurd and profound, as humanity is left with a cosmic punchline: an answer without a question.This mix of comedy and philosophy made 42 a lasting cultural symbol. Since then, it has often been used in science, technology, and pop culture as a playful way to say that some questions about existence may never have a neat or simple solution.When Elon Musk chose to design Starship with 42 engines, it was not only about meeting technical needs. It was also a cultural reference that many science fiction fans immediately recognized. To those in the know, it was like Musk giving a little wink, a way of saying that building rockets is not just about nuts and bolts but also about imagination, humor, and philosophy. Musk has often spoken about being inspired by science fiction, and using the number 42 connects SpaceX’s real-world work with the stories and ideas that have inspired dreamers for decades.Of course, the choice also makes sense from an engineering perspective:For most people, Starship’s 42 engines might simply look like the result of engineering calculations. But the choice also carries a deeper message. Just as Douglas Adams used the number 42 to make readers laugh while thinking about existence, Musk is using the number to remind us that space exploration is not only about technology. It is also about purpose, imagination, and humanity’s search for meaning.In that sense, the rocket becomes more than a machine. It becomes part of a story about where we are going as a species and why we dare to reach for other worlds.