ホット・ジュピター
KELT-2Ab is an extrasolar planet that orbits the star KELT-2A approximately 440 light-years away in the constellation of Auriga. It was discovered by the KELT-North survey via the transit method, so both its mass and radius are known quite precisely. As of its discovery KELT-2Ab is the fifth-brightest transiting Hot Jupiter known that has a well constrained mass. This makes the KELT-2A system a promising target for future space- and ground-based follow-up observations to learn about the planet's atmosphere.