New Delhi, May 13 -- Neil deGrasse Tyson has had a lifelong fantasy of being abducted by aliens. That's right, he actually wants to be taken.

"I even picture the scenario in my head: I'm sitting out there alone, and a beam of light comes down," he says. "It's not a spacecraft that's hovering over me. It's just a beam of light from space. And I just get lifted up into that beam of light, and I appear in a new place."

America's favorite astrophysicist has turned that lifelong fascination into a book, "Take Me to Your Leader: Perspectives on Your First Alien Encounter," which - like that beam of light - illuminates what we know about possible space critters and what we can anticipate if they ever come calling.

"Even if it doesn't actually...