Musicians leave bands for all sorts of reasons: artistic differences, ego clashes, drug or alcohol abuse, even boredom.

But there can't be many like Tom DeLonge. The guitarist and singer has revealed that he quit Blink-182 last year to further his research into... UFOs.

"I've always had a passion for space and the future," the 40-year-old said in an interview with Mic.com. "When you're an individual like me, dealing with something that's a national security issue, and you're being gifted with the opportunity to communicate something you've been passionate about your whole life – something that has the opportunity to change the world over time – being a small part of that is enormously important for my life path.

"But I can't do everything. I can't tour nine months out of the year with enough time to do the enormity of what I'm setting out to do."