You can't answer the question "how long does it take to travel one astronomical unit" without knowing what you're traveling with.

Here's why:

* An astronomical unit (AU) is a unit of distance, roughly the average distance between the Earth and the Sun. It's about 93 million miles.

* Speed is crucial: The time it takes to travel one AU depends entirely on how fast you're going.

Here are some examples:

* Light: Light travels at the fastest speed possible – the speed of light. It takes light approximately 8.3 minutes to travel one AU.

* Spacecraft: Spacecraft vary greatly in speed. A typical spacecraft might take several months to travel one AU.

* A commercial airplane: At its cruising speed, a commercial airplane would take many years to travel one AU.

To answer your question accurately, you need to tell me:

* What is traveling? (e.g., light, spacecraft, airplane, etc.)

* What is its speed?

Let me know those details, and I can give you a precise answer!