Dec. 14, 2017
Research Highlight
A Search for Stellar Companions
This artist's concept shows the orbits of a triple-star system called HD 188753, which was discovered to harbor a gas giant, or "hot Jupiter," planet.Image credit: NASA/JPL-Caltech.
A team of researchers have performed a systematic speckle imaging survey of 71 stars known to host exoplanets in an attempt to detect low-mass companions of the stars. In their survey, the team found only two stars that showed evidence of having stellar companions down to the detection limit of the instrumentation used (Differential Speckle Survey Instrument at the Gemini-north Observatory).
NASA's Spitzer Space Telescope captured this picture of a nearby star and its orbiting companion. The two infrared images show a faint object moving through space together with a dead star called a white dwarf.Image credit: NASA/JPL-Caltech/Penn State.
Astronomers have detected many systems where the primary star shares its space with a companion object, a phenomenon known as stellar multiplicity. In such cases, the star and its companion object orbit the system’s common center of gravity. It is easy to identify multiple-star system when companion objects are bright, but sometimes companion objects can be very dim. Understanding how this multiplicity might impact the properties of exoplanets is essential in understanding the potential habitability of these systems.
The study, “Exclusion of Stellar Companions to Exoplanet Host Stars,” was published in The Astronomical Journal. The work was supported by the Nexus for Exoplanet System Science (NExSS). NExSS is a NASA research coordination network supported in part by the NASA Astrobiology Program. This program element is shared between NASA’s Planetary Science Division (PSD) and the Astrophysics Division.