THYME project discovers a sub-Neptune exoplanet orbiting a young star

Astronomers report the discovery of a new sub-Neptune exoplanet as part of the TESS Hunt for Young and Maturing Exoplanets (THYME) program. The newfound alien world, named HD 110082 b, is about three times the size of Earth and orbits a relatively young star. The finding is reported in an article published on February 11 on arXiv.org.

NASA’s Transiting Exoplanet Survey Satellite (TESS) is conducting a survey of about 200,000 of the brightest stars near the sun with the aim of searching for transit exoplanets. To date, he has identified nearly 2,500 candidate exoplanets (TESS Objects of Interest, or TOI), of which 107 have been confirmed so far.

The THYME collaboration aims to identify planets that populate stars in nearby, young, older residents. To date, the project has detected three extrasolar planetary systems and the finding of another one is reported in a recent publication. The team, led by Benjamin M. Tofflemire of the University of Texas at Austin, identified a transit signal in the light curve of the star HD 110082 (or TOI-1098). The planetary nature of this signal has been confirmed by follow-up observations.

“We report on the discovery of a sub-Neptune-sized planet orbiting the young star HD 110082 (TOI-1098). Transit events we initially detected during TESS cycle 1 are confirmed by time series photometry of Spitzer. Images with high contrast and high-resolution optical spectra are also obtained to characterize the stellar host and confirm the planetary nature of the passages, ‘the astronomers wrote in the study.

HD 110082 b has a radius of about 3.2 earth rays and is assumed to be about 11 times more massive than our planet. It orbits its host every 10.18 days, at a distance of about 0.113 AU from there. The transit duration of this planet indicates that it has a low orbital eccentricity, probably at a level of about 0.2. Since the HD 110082 system is expected to be relatively young (about 250 million years old), the newfound alien world can be very useful in testing planet formation and evolutionary theories.

The parent star is located of the spectral type F8V, about 343 light-years away. It has a radius of about 1.19 sunbeams and a mass of about 1.12 solar masses. The star has an effective temperature of about 6 200 K and a metal at a level of about 0.08. It is assumed that the object resides in a young young star association called MELANGE-1.

The findings provide important clues about the parameters of young extracurricular worlds in general. “HD 110082 b’s radius falls in the largest 12 percent of field age systems with a similar gas mass and orbital period. This finding supports previous studies indicating that young planets have larger radii than their field age counterparts,” the authors of the article said. said. ended.

The astronomers also found that HD 110082 has an M dwarf mate with a low mass. The object is estimated to have a mass of about 0.26 solar masses and is separated from HD 110082 by about 6,200 AU.

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