Black holes do not exist—at least, not as we know them, says renowned physicist Stephen Hawking, potentially provoking a rethink of one of space's most mysterious objects.

A new study from Hawking also says that black holes may not possess "firewalls," destructive belts of radiation that some researchers have proposed would incinerate anything that passes through them but others scientists deem an impossibility.

(Editor's note: Watch for our feature "The Truth About Black Holes" in the March issue of National Geographic magazine, out February 15.)

The conventional view of black holes posits that their gravitational pull is so powerful that nothing can escape from them—not even light, which is why they're called black holes. The boundary past which there is