Two-Spacecraft Laser Tracking for Detecting Gravitational Waves

A paper proposes a method of mutual coherent laser tracking of two spacecraft for detecting gravitational radiation. Each spacecraft would transmit a laser beam to, and receive a similar laser beam from, the other spacecraft. Each spacecraft would also coherently transpond a laser beam back to the other spacecraft. Comparison of the phases of the various transmitted and received signals would yield four sets of tracking data - two sets of one-way and two sets of two-way Doppler shifts that could be partly attributable to gravitational waves. The data would be time-tagged and telemetered back to Earth for analysis.