My apologies. I agree that the English expression is inaccurate in the context of the quoted passage.

In the Japanese version, the word "star" (星/hoshi) is only used in the headline.
コスモエクスプローラー 新たな星「ガラスの星 パエンナ」
Here is a literal translation from Japanese:
Cosmo Explorer: A New Star, "Phaenna, the Glass Star"

This is the Japanese counterpart of the English below.
Cosmic Exploration: Phaenna
The Japanese sentence does not sound unnatural. But in this context, it should be "planet," not "star," in English, just like in the German and French versions.