HR 2562 B is a substellar companion orbiting the star HR 2562. Discovered in 2016 by a team led by Quinn M. Konopacky by direct imaging, HR 2562 B orbits within the inner edge of HR 2562's circumstellar discas of April 2023, it is one of only two known brown dwarfs to do so. Separated by roughly from its primary companion, HR 2562 B has drawn interest for its potential dynamical interactions with the outer circumstellar disc.
Discovery HR 2562 B was discovered using the Gemini Planet Imager (GPI), which first observed the star HR 2562 in January 2016. In the initial data set, Konopacky and collaborators identified a candidate companion object. As a result, followup observations were conducted within the following month in the infrared K1-, K2-, and J-bands. Within the processed data set, HR 2562 B was confirmed to share a common proper motion with HR 2562, with Konopacky and collaborators announcing its discovery in a paper published on 14 September 2016.
Properties Orbital properties Initial observations of HR 2562 B by Konopacky and collaborators yielded a separation of , placing it interior to and coplanar with the inner edge of HR 2562's observed debris disc. Further observations of HR 2562 B by the Atacama Large Millimeter Array (ALMA) supported this, yielding a semi-major axis of , an orbital period of , and an orbital eccentricity of . With a probable orbital inclination of , HR 2562 B's misalignment angle with the debris disc is either or . However, the limited coverage of observations still leaves a wide range of possible orbits; both low-eccentricity, coplanar orbits and high-eccentricity, misaligned orbits would be consistent with observation data. However, a highly misaligned orbit would significantly perturb the disc, suggesting that a low-eccentricity, coplanar solutions are likelier. A 2025 study using astrometry and radial velocity refined the orbital elements, finding a separation of 22.2 AU, a significantly lower eccentricity of 0.34, and an inclination of 86.7°, which implies a planet-disk inclination of °.
Physical properties HR 2562 B's mass was first estimated in 2016 at , based on measurements of its luminosity and age compared to the predictions of evolutionary models. This was later revised to in 2021. However, astrometric observations placed an upper mass limit of and later . Atmospheric modelling of the spectral energy distribution indicates a mass of , an effective temperature of , and a luminosity of . The spectral type is .
See also PZ Telescopii B, another substellar object with mass slightly below
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