"There are at least 300,000 near-earth objects," that could potentially hit our planet said Daniel Durda, an asteroid expert from the Southwest Research Institute. Durda, who was George Noory's guest the very first time he hosted Coast in April of 2001, returned to the show this Tuesday night.

"I'm on the side that we should keep this out in the open," Durda weighed in on the recent controversy over whether a government should warn its populace of an imminent asteroid hit. Besides "it's pretty much impossible to hide the evidence of an impending impact," he said. If one of the smaller near-earth objects were to hit our planet, say the size of a football field, the ensuing airburst would be similar to the Hiroshima blast Durda speculated. The object would likely explode while still in the air from the intense aerodynamic pressure, he added.

Durda characterized the planet Jupiter as a kind of protector of the solar system in that the large body draws in a lot of comets and asteroids that otherwise might travel our way. While the huge gas planet weighs as much as 318 Earths, it only has the amount of solid material contained in one Earth, he said. As to the arrival of a Planet X in our solar system, Durda wasn't anticipating such a body, though he did say objects in the outer solar system might be extremely dark and hard to find.