SpaceX CEO Elon Musk not only wants to explore Mars, he wants to ‘nuke’ it.

In a tweet this week, Musk reiterated calls to ‘Nuke Mars!’ adding that t-shirts are ‘coming soon.’

Jarring though the idea may be, the tweet is a re-hash of an idea championed by Musk in the past that proposes using a nuclear weapon to terraform the red planet for human habitation.