Astronomers from the University of Maryland and elsewhere have announced the recent discovery of a new mini-Neptune exoplanet designated TOI-283 b. This fascinating planet circles an active K-type star, TOI-283, about 269 light years from Earth. The study mapping out this finding was released onto the pre-print server arXiv on October 16.
Among those aforementioned planets, TOI-283 b really stands out, and not just for its amusingly high mass and size. This mini-Neptune has a radius slightly larger than 2.34 times Earth’s. It has a mass about 6.54 times greater than the size it occupies, making it relatively massive for such a dense planet. It takes just 17.62 days to complete its orbit around its host star. This recently discovered celestial body orbits at a distance of ~ 0.12 AU from its host star.
Characteristics of TOI-283
The host star, TOI-283, offers an interesting profile. At an estimated 10.4 billion years of age, it is 15% smaller and 20% less massive than our own Sun. Its effective temperature is about 5,213 K, which leads to the exciting environment around TOI-283 b. The iron abundance of TOI-283 is determined at a level of -0.09 dex, placing the star’s metallicity among the Hyades Cluster values.
The age and characteristics of TOI-283 make this a particularly valuable system with which to explore the planetary system’s context. The star’s extraordinary age means that it’s been around long enough to witness the birth and death of entire galaxies over billions of years. This uniqueness makes it a great target for future studies of stellar evolution and planetary formation.
Orbital and Physical Properties of TOI-283 b
The fact that TOI-283 b’s orbital properties are unusual only adds to its charm. The planet is very close to its host star, orbiting at only 0.12 AU. Such close proximity results in a high equilibrium temperature of 661 K. This temperature indicates that the planet likely has some sort of active atmosphere capable of maintaining global weather patterns. The finer points have yet to be worked out.
TOI-283 b has a rather low density of 2.81 g/cm³. Even though it is about 40% smaller than Neptune, it still has an impressive mass for its size class. Ultimately, the researchers hope that such characteristic would shed light on the formation pathways of mini-Neptunes and help to understand their atmosphere compositions.
“The planet candidate was first detected by NASA’s TESS mission; ground-based observations confirmed that the star has no detectable stellar companions and that the transits occur on the star TOI-283. High-precision RV [radial velocity] measurements made with the VLT’s ESPRESSO instrument enabled the mass of the planet candidate to be determined,” – Felipe Murgas et al, in Murgas et al.
Implications of the Discovery
The detection of TOI-283 b is a contribution to the growing catalog of exoplanets. This amazing discovery is only possible thanks to missions such as TESS, NASA’s Transiting Exoplanet Survey Satellite. As astronomers continue to refine their observational techniques, planets like TOI-283 b can help enhance understanding of diverse planetary systems across the galaxy.
Specifically, understanding this mini-Neptune will help us better understand the formation and evolution of these planets around K-type stars. Its unique characteristics, combined with the age of its host star make for an amazing opportunity for researchers. Because of this, they’re able to envision long-term planetary development more than ever before.