From above a planet about twice the size of Jupiter, this artist’s conception shows the star that planet is orbiting and that star’s binary companion in the distance. Credit: Sophia Dagnello, NRAO/AUI/NSF
Astronomers have discovered a Very Long Baseline Array (VLBA).
Although more than 5,000extrasolar planets have been discovered so far, only three have been discovered using a technique called astrometry, which was used to produce this discovery. However, the feat of determining the 3-D architecture of a binary-star system that includes a planet “cannot be achieved with other
In this artist’s conception, a small star (orange) is orbited by a Jupiter-like planet (blue), and by a more-distant companion star (red). Credit: Sophia Dagnello, NRAO/AUI/NSF
The two stars, which together are called GJ 896AB, are about 20 light-years from Earth. That makes them close neighbors of ours by astronomical standards. They are red dwarf stars, the most common type of star in our Artist’s animation illustrates the orbital motions of a binary star pair and a planet orbiting one of the stars. Credit: Sophia Dagnello, NRAO/AUI/NSF
The existence of the planet was revealed by a detailed tracing of the larger star’s motion that showed a slight wobble. The planet’s gravitational effect on the star causes the wobble. The star and planet orbit a location between them called the barycenter, which represents their common center of mass. When that location is sufficiently far from the star, the star’s motion around it can be detectable.
According to calculations by the astronomers, the planet has about twice the mass of Jupiter and orbits the star every 284 days. Its distance from the star is slightly less than Next Generation VLA (ngVLA),” said Amy Mioduszewski, of the National Radio Astronomy Observatory. “With it, we may be able to find planets as small as the Earth.”
The astronomers reported their findings in the September 1 issue of the Astronomical Journal.
Reference: “3D Orbital Architecture of a Dwarf Binary System and Its Planetary Companion” by Salvador Curiel, Gisela N. Ortiz-León, Amy J. Mioduszewski and Joel Sanchez-Bermudez, 1 September 2022, Astronomical Journal. DOI: 10.3847/1538-3881/ac7c66
The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
