Two Jovian-Mass Planets in Earthlike Orbits

TL;DR

This paper reports the discovery of two Jupiter-mass planets in orbits similar to Earth's, with low eccentricity, around stars HD 5319 and HD 75898, using radial velocity measurements.

Contribution

First detection of two Jupiter-mass planets with Earth-like orbits and low eccentricity around their host stars.

Findings

Planets have low eccentricity (~0.10-0.12).

Orbits are within 1-2 AU, similar to terrestrial planets.

Radial velocity residuals suggest additional companions.

Abstract

We report the discovery of two new planets: a 1.94 M_Jup planet in a 1.8-year orbit of HD 5319, and a 2.51 M_Jup planet in a 1.1-year orbit of HD 75898. The measured eccentricities are 0.12 for HD 5319 b and 0.10 for HD 75898 b, and Markov Chain Monte Carlo simulations based on derived orbital parameters indicate that the radial velocities of both stars are consistent with circular planet orbits. With low eccentricity and 1 < a < 2 AU, our new planets have orbits similar to terrestrial planets in the solar system. The radial velocity residuals of both stars have significant trends, likely arising from substellar or low-mass stellar companions.