Use "unchallengeable" in a sentence

1. In planning their journeys to the moon they must take fully into account these unalterable and unchallengeable laws, or face disaster.

2. “ Bankrupting Physics is a blunt, but entertaining account of the current state of fundamental physics. The reader may not necessarily have the same opinion as the authors, but they will bear witness to some of the field's unchallengeable high priests in action, and question whether the system itself is now in a period of stagnation.