Can "煌天" be read as "Bright Sky?"

I know that "天" is "heaven" or "sky," but I think in this context the latter is more appropriate, as for "煌" most of the results I found were "glittering" or "gleaming," but I was curious if something simple like "bright" would still be a faithful way to translate it.

It depends on the context. If it is a poetic context, glittering or shining or gleaming might be better. If its a name that is repeated over and over, something more familiar to the western ear ("bright sky" as you suggest) might be a better choice. Either way, you are not far at all from the original meaning, and it becomes almost a question of style, and what impact the writer intends.