[kloch]

> n 1976, while Van Flandern was employed by the USNO, he began to promote the belief that major planets sometimes explode.[30] Van Flandern also speculated that the origin of the human species may well have been on the planet Mars, which he believed was once a moon of a now-exploded "Planet V".

https://en.wikipedia.org/wiki/Tom_Van_Flandern#Exploding_pla...