Maybe they just figure they're keeping us out of sensor range.

"But it's moving toward us, and it certainly wasn't within sensor range when we first arrived here."

"On our present course, will we come within their sensor range?"

But in those few minutes, he shuttle would make it well out of sensor range.

The first of our two targets is within sensor range.

"We have just closed to within sensor range of the system."

They will be within local sensor range in about fifteen minutes or so.

It had barely moved into sensor range when all its systems failed.

"It should be entering our own sensor range at any moment."

Once the wave came within sensor range, they would only have a few minutes.