Solar System Ephemerides, Pulsar Timing, Gravitational Waves, and Navigation

TL;DR

This paper discusses how uncertainties in the solar system barycenter impact pulsar timing arrays used for gravitational wave detection and explores future spacecraft navigation improvements.

Contribution

It analyzes the influence of solar system barycenter uncertainties on pulsar timing and gravitational wave research, highlighting the need for precise spacecraft navigation.

Findings

Uncertainties in the solar system barycenter affect pulsar timing accuracy.

Refinements in planetary ephemerides are crucial for gravitational wave detection.

Future spacecraft navigation can reduce barycenter uncertainties.

Abstract

In-spiraling supermassive black holes should emit gravitational waves, which would produce characteristic distortions in the time of arrival residuals from millisecond pulsars. Multiple national and regional consortia have constructed pulsar timing arrays by precise timing of different sets of millisecond pulsars. An essential aspect of precision timing is the transfer of the times of arrival to a (quasi-)inertial frame, conventionally the solar system barycenter. The barycenter is determined from the knowledge of the planetary masses and orbits, which has been refined over the past 50 years by multiple spacecraft. Within the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), uncertainties on the solar system barycenter are emerging as an important element of the NANOGrav noise budget. We describe what is known about the solar system barycenter, touch upon how uncertainties in it affect gravitational wave studies with pulsar timing arrays, and consider future trends in spacecraft navigation.