Scientists have announced the discovery of two giant exoplanets. A preprint article about it was published at arXiv.org. The finding comes from observations made with the TESS space telescope, which is specially tuned to hunt for exoplanets. Its instruments detect minute dips in starlight when a planet passes in front of its host star, revealing the planet’s presence. In this study, signals consistent with planets were seen around two red dwarf stars, TOI-3984A and TOI-5293A, which form a binary system. TOI-3984A b has a radius near 0.71 times that of Jupiter and a mass around 0.14 Jupiter masses, placing it in the sub-Saturn category. Its orbital period is about 4.35 days, the orbital distance is roughly 0.041 astronomical units, and its equilibrium temperature sits near 563 kelvin. The host star of this planet weighs about half the mass of the Sun, and the system lies at a distance of approximately 353 light-years from Earth in the constellation of year.
TOI-5293A b matches the size of Jupiter but is lighter, with a mass near 0.54 Jupiter masses. Its rotation period clocks in at about 2.93 days, and its orbital distance is roughly 0.034 astronomical units. Identified as a hot Jupiter, this planet experiences a surface temperature near 675 kelvin, making it hotter than the first planet. The central star in this system is also about half the Sun’s mass, yet it lies about 524 light-years away.
Overall, the researchers behind the arXiv submission emphasize that TOI-3984A b and TOI-5293A b represent two of the coldest hot gas giants found among Jupiter-sized exoplanets orbiting M-dwarfs, highlighting an intriguing contrast in planetary atmospheres and orbital dynamics within binary red dwarf systems.