Perihelion passage

Japanese: 近日点通過 - きんじつてんつうか

… Keplerian elements, for celestial bodies orbiting the Sun, consist of the following six constants (see figure): (1) semimajor axis a , (2) eccentricity e , (3) inclination i , (4) longitude Ω of ascending node, (5) argument of perihelion ω, and (6) time and date of perihelion T. In the motion of the Moon and artificial satellites, ω is called the argument of perigee, and T is called the time and date of the perigee passage. …

From [Perihelion]

…On the other hand, the point farthest from the Sun is called the aphelion. The time when a celestial body passes the perihelion is called the perihelion passage, and the distance from the Sun to the perihelion is called the anomaly. The Earth's perihelion is about 147 million km away from the Sun, and the perihelion passage occurs in early January. …

*Some of the terminology used to refer to "perihelion passage" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…　ケプラー要素は，太陽を公転する天体の場合には，次の6個の定数から成る（図）。(1)軌道半長径a，(2)軌道の離心率e，(3)軌道傾斜i，(4)昇交点黄経Ω，(5)近日点引数ω，(6)近日点通過の日時T。月や人工衛星の運動ではωは近地点引数，Tは近地点通過の日時と呼ばれる。…