HAMPTON, VIRGINIA -- Think of the Earth tagged with a huge sign: WARNING! FALLING ROCKS.

There are certifiable, true-to-life "rocky horror shows" in our future...and the picture is not pretty.

If any one of them were to hit our planet, social and environmental havoc would ensue. Locating the whereabouts of a majority of these objects is the central task of several ground-based telescopic searches now underway.

Mazanek told SPACE.com that a far greater number of near-Earth asteroids (NEAs) exist that are around 300 feet (100 meters) across or smaller. Millions of these size objects may exist, he said.

"What we’re undertaking with CAPS is finding out what it takes to expand the range of detectable objects both in size and distance, to try and cover the entire hazard," Mazanek said. The hope is coming up with technology and a strategy to scan the entire celestial sky on a regular basis, to create a continuous warning system that can be implemented within 20 to 40 years.

The RASC goal is to develop a system concept that maximizes the range of detectable objects, and provides a high probability that the objects will be detected with significant warning time, even upon their first observed near-Earth approach.

CAPS study members are evaluating a range of threats.

For one, smaller-sized asteroids could cause localized damage. Impact near an urban area or coastline could result in considerable loss of life, extensive damage, and economic disruption. Potentially, even a smaller-sized asteroid hit could rack up trillions of dollars worth of destruction.

In all probability, Mazanek said, the next object that does hit us will be in the 165 feet (50 meter) to 330 feet (100 meter) size. "We hope it hits somewhere without ramifications," he said.

Then there are the nastier long period comets. They do not regularly saunter their way into near-Earth space, having orbital periods that can measure many millions of years before announcing themselves. They too are a possible threat and can offer little or no warning time using conventional ground-based telescopes, Mazanek noted.

"In all likelihood, the ground-based telescopes are not going to have the sensitivity to pick up these objects with enough time," Mazanek pointed out. The group has set as a benchmark the spotting of a one kilometer-sized comet at 5 to 7 Astronomical Units (AU) from Earth. One AU is roughly 93 million miles (150 million kilometers). "Depending on its orbital trajectory, that would give you somewhere around a year’s worth of warning time," he said.

Then there are objects that get perturbed, making their whereabouts a chancy state of affairs. "A whole host of objects exist that, over a period of time, their orbits will change. Being able to pick those out would be beneficial," Mazanek stated.