There exists a pair of straight lines that are at constant distance from each other.

I set the control system to hold us at a constant distance from the surface of Manna.

The subject is told to keep the lead car at a constant, safe distance.

If so, how could they stay motionless, at a constant distance from each other?

For though she had lived in the city very little, most of her life had been spent at a constant distance from it.

They should not remain motionless, at a constant distance from each other, but should all fall together to some central point.

It's keeping at a constant distance, and I hope it stays there.

They keep a constant distance from each other with remarkably few adjustments.

It moved slowly left to right, staying a more or less constant distance above the desert floor, then suddenly winked out.

They need not maintain a constant distance from the primary.