认识一颗具有地球（Earth）般温度的土星（Saturn）大小系外行星（exoplanet）

TOI-199b是一颗距离地球330光年（light year）的系外行星，其体积与土星相当。韦布空间望远镜（space telescope）的最新观测结果显示，该行星大气中存在甲烷。

TOI-199b is a warm Saturn-sized exoplanet 330 light-years away. New observations by the Webb space telescope show there is methane in its atmosphere. The post Meet a Saturn-sized exoplanet with Earth-like temperatures first appeared on EarthSky .