Galactic Accelerometry via Millisecond Pulsar Timing*

Millisecond pulsars serve as precise astronomical clocks distributed throughout the Milky Way. The galactic acceleration experienced by pulsars manifests as chirps in their periodic signals. Using pulsar timing data, we can measure the local galactic acceleration, which can be used to reconstruct the galactic gravitational potential, similar to the techniques used to measure Earth's gravitational potential using terrestrial atomic clocks. We present the first measurement of the local Galactic acceleration using the orbital periods of an ensemble of 13 binary millisecond pulsar systems. Local acceleration is measured with 3σ precision and in good agreement with expectations. This work is a first step toward dynamically measuring acceleration gradients that will eventually inform us about the dark matter density distribution in the Milky Way galaxy.