Evolution of INPOP planetary ephemerides and Bepi-Colombo simulations

TL;DR

This paper details the latest INPOP20a planetary ephemerides, evaluates potential violations of general relativity, and assesses Bepi-Colombo data's impact on improving planetary models and detecting Sun core rotation.

Contribution

It introduces new evaluations of GRT violations, a novel method for selecting ephemerides, and simulations of Bepi-Colombo data to enhance planetary ephemerides and Sun core rotation detection.

Findings

Limits on GRT violation parameters $eta-1$ and $ ext{"gamma"}-1$

Simulated Bepi-Colombo data improve parameter estimates

Potential to detect Sun core rotation with Bepi-Colombo measurements

Abstract

We give here a detailed description of the latest INPOP planetary ephemerides INPOP20a. We test the sensitivity of the Sun oblateness determination obtained with INPOP to different models for the Sun core rotation. We also present new evaluations of possible GRT violations with the PPN parameters $\beta$,$\gamma$ and $\dot{\mu}/\mu$. With a new method for selecting acceptable alternative ephemerides we provide conservative limits of about $7.16 \times 10^{-5}$ and $7.49 \times 10^{-5}$ for $\beta-1$ and $\gamma-1$ respectively using the present day planetary data samples. We also present simulations of Bepi-Colombo range tracking data and their impact on planetary ephemeris construction. We show that the use of future BC range observations should improve these estimates, in particular $\gamma$. Finally, interesting perspectives for the detection of the Sun core rotation seem to be reachable thanks to the BC mission and its accurate range measurements in the GRT frame.