AU Mic b

AU Mic b joins the Codex as a Neptune-sized world racing around a still-forming red dwarf only about 32 light-years away. Roughly 4.8 × Earth across, it transits a violently young M1 star whose dusty debris disk still sparkles with planetesimal collisions. Discovered in 2020, the planet completes an orbit in a little over eight […]

WASP-107 b

WASP-107 b enters the Codex as a famously fluffy warm Neptune, a low-density giant that transits a quiet K-type star about 211 light-years away. Its radius stretches to roughly 10.5 × Earth while its mass stays near Neptune’s, a Saturn-scale balloon around a heavy core. JWST spectra caught photochemical sulfur dioxide, silicate clouds, water, and […]

HAT-P-11 b

HAT-P-11 b stands in the Codex as a true ice giant that transits a bright orange K-type dwarf 123 light-years away. With a radius of 4.4 × Earth and a mass near 25 Earths, it is a Neptune analog Kepler watched for years. It completes an orbit every 4.9 days at 0.053 AU, far too […]

GJ 436 b

GJ 436 b stands as a warm ice giant orbiting a nearby red dwarf M-type star 32 light-years from Earth. With a radius of 4.2 × Earth and a mass of 22.1 Earth masses, it completes an orbit every 2.64 days at 0.029 AU, far inside the habitable zone. Intense stellar heat drives a vast […]