Prospects for localising Planet 9 with a future Uranus mission

Abstract

Past years have seen various publications attempting to explain the apparent clustering features of trans-Neptunian objects, the most popular explanation being an unconfirmed "Planet 9". The recently proposed Uranus Orbiter and Probe mission by NASA's Planetary Science and Astrobiology Decadal Survey could offer the opportunity to precisely determine Planet 9's sky location and mass by carefully monitoring ranging data during the interplanetary cruise. We use Monte Carlo-Markov Chain methods to reconstruct simulated spacecraft trajectories in a simplified solar system model containing Planet 9, providing an estimate of the mission's localisation capacity depending on sky location, Earth-spacecraft Doppler link noise level and data collection rate. We characterise the noise via the Allan deviation ${\sigma }_{\mathrm{A}}$, scaled to the Cassini-era value ${\sigma }_{\mathrm{A}}^{\mathrm{Cass}}=3\times 10^{-15}$, finding that daily measurements of the spacecraft position can lead to $\sim$0.2 deg${}^2$ localisation of Planet 9 (assuming $M_9=6.3M_{\oplus }$, $d_9=460$AU). As little as a 3-fold improvement in ${\sigma }_{\mathrm{A}}$ drastically decreases the sky localisation area size to $\sim$0.01 deg${}^2$. Thus, we showcase that a future Uranus mission carries a significant potential also for non-Uranian science.

Accepted for publication in MNRAS: Letters, 5 pages, 4 figures

References in corpus (9)

• astroquery: An Astronomical Web-Querying Package in Python
• The New Horizons Spacecraft
• The inclination of the planetary system relative to the solar equator may be explained by the presence of Planet 9
• A serendipitous all sky survey for bright objects in the outer solar system
• Was Planet 9 captured in the Sun's natal star-forming region?
• Searching for gravitational waves via Doppler tracking by future missions to Uranus and Neptune
• One EURO for Uranus: the Elliptical Uranian Relativity Orbiter mission
• Mean plane of the Kuiper belt beyond 50 AU in the presence of Planet 9
• Searching for giant planets in the outer Solar System with far-infrared all-sky surveys