Retrieving "Periapsis Distance" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

  1. Semi Major Axis

    Linked via "Periapsis Distance ($r_p$)"

    The distances to the apsides are then calculated as follows:
    Periapsis Distance ($r_p$): The closest approach distance (e.g., perihelion for the Sun/), perigee for Earth).
    $$r_p = a(1 - e)$$
    Apoapsis Distance ($r_a$): The farthest distance (e.g., aphelion or apogee).