Perigee is a point in a satellite’s orbital path, representing the closest distance to the celestial body it orbits, such as Earth. In Earth orbits, the perigee marks the lowest point along the satellite’s trajectory.

As the satellite travels around the celestial body, it experiences gravitational forces that govern its motion, resulting in a continuous variation in distance from the celestial body’s centre. At the perigee, the satellite reaches its minimum altitude, coming closest to the Earth’s surface.

The perigee, along with the apogee (the point farthest from the celestial body), determines the overall shape and size of the satellite’s orbit. Together, these two points define the eccentricity of the orbit. An orbit with a low eccentricity value is nearly circular, while higher eccentricities result in more elongated or elliptical orbits.