TOI-3523 A b: A Jupiter-Like World in a Distant Triple System

TOI-3523 A is a star 2100 light-years away with an age of 4.3 billion years. Its mass is 1.13 solar masses, its radius is 1.45 solar radii, and its temperature is 6450 K. Each of these measurements describes the host star itself rather than the wider system. The star's reported mass estimate is larger than the Sun's, and its reported radius estimate is also larger than the Sun's. Its reported temperature is hotter than the Sun's. One planet orbits this host.

That planet, TOI-3523 A b, is a Jupiter-like world discovered by transit in 2025. A transit occurs when a planet passes in front of its star from our viewpoint, causing a small dip in observed brightness. TOI-3523 A b has a mass of 435 Earth masses, a radius of 16 Earth radii, and an orbital period of 2.3 days. Its reported radius estimate is larger than Earth's, and its reported mass estimate is larger than Earth's. Its reported mass estimate is roughly 1.37 times Jupiter's mass. The planet's mean density is 0.589 g/cm³, 0.107 times Earth's. Being Jupiter-like, it exceeds 4 times Earth's radius.