The equipment we brought for this mission is aimed at detecting objects on or below the planet's surface, not ships overhead.

As Tom throttled back and started to descend he detected a puff of white smoke miles below them.

To be safe, you need to detect hydrogen levels well below four percent.

Several times he thought he detected movement below the brow of the hill.

It will not be able to detect, with any significant degree of confidence, nuclear testing below 1 kiloton.

That digestive pouch you detected below the stomach is one tough little organ.

Did he detect a shade of surprise on the broad face below the cap?

Their sense of smell is strong enough to detect grubs three feet below ground.

The measurements can detect hydrogen only about a yard below the surface.

Or how about a Saint Bernard that can detect signs of life below an avalanche?