Learn Turkish: Şu gezegende büyük bir koloni olur muydu? - Would there be a big colony on that planet?

This is a combination of the aorist tense (olur, meaning "it happens" or "it is") and the past tense question particle (muydu). When you add the past tense to the aorist in a question format, it creates a hypothetical or conditional meaning, translating perfectly to "would it be?" or "would there be?" in English.

Could I use o instead of şu for "that planet"?

Yes, o gezegende would also mean "on that planet." However, Turkish speakers often use şu when they are actively drawing attention to something, pointing it out in the moment, or introducing a new focus of conversation. O is more neutral and often refers to something already established in the discussion.

Why is the word order büyük bir koloni instead of bir büyük koloni?

In Turkish, when a noun has both a descriptive adjective (büyük) and the indefinite article bir, the standard word order is Adjective + bir + Noun. Saying bir büyük koloni sounds unnatural to a native speaker.

What is the exact breakdown of the word muydu?