The adverb in the sentence "We looked up at the meteor" is up.

Here's why:

* Adverbs modify verbs, adjectives, or other adverbs. They tell us how, when, where, or to what extent something happens.

* In this sentence, "up" tells us how we looked, providing more information about the verb "looked".

Let me know if you'd like to explore other examples of adverbs!