Precision Astrometry Using Optically Independent Spacecraft for Graviational Wave Detection

1 min read Preparations for Next Moonwalk Simulations Underway (and Underwater) Graphic depiction of the Graviational Wave Detection concept. Paul Stankus Paul Stankus Brookhaven Science Associates  The scientific goal is to enable a new method for observing gravitational waves at low frequencies, based on the astrometric GW signature — gravitational waves passing by the Earth will cause a (very small) coordinated apparent motion of all sky objects. Our innovation is to deploy a new approach to precision astrometry using quantum mechanical two-photon interference, which was published quite recently.

The approach has the great benefit that two separate interferometric spacecraft stations can operate independently, ie without an optical connection between them, greatly simplifying spacecraft requirements compared to standard space-based interferometric designs. With this capability we propose to be able to detect passing gravitational waves at low frequencies, in the micro-Hz to nano-Hz range, at a sensitivity at an astronomically interesting level (note that there are, currently, essentially no alternative approaches for GW detection in this band). We show how this could be achieved with a straightforward mission using two modest-sized spacecraft in free-fall orbits; and detection of such GW’s would be of great interest for galaxy formation and SM black hole physics, as well as exciting the public imagination.