MASCARA-4 b: A Jupiter-like Planet Around a Hot A-Type Star

MASCARA-4 is a star 557 light-years away with a spectral type of A7 V, an A-type main-sequence dwarf. It hosts one known planet. The star's reported mass estimate is 1.75 solar masses, larger than the Sun's, and its reported radius estimate is 1.92 solar radii, also larger than the Sun's. Its reported temperature is 7800 K, hotter than the Sun's. The star's age is 0.8 billion years.

The planet, MASCARA-4 b, is Jupiter-like and was discovered in 2020 by the transit method, in which a planet passes in front of its star from our viewpoint and causes a small dip in observed brightness. Its orbital period is 2.82 days. Its radius is 17 Earth radii, larger than Earth's, and its mass is 532 Earth masses, larger than Earth's and roughly 1.68 times Jupiter's mass. Its mean density is 0.599 g/cm³, 0.109 times Earth's.