Apollo-type Orbit
An Apollo-type orbit is the path of an asteroid that crosses Earth's orbit, with its farthest point extending beyond Earth toward Venus. This elongated trajectory brings the object close to Earth, making it a potential impactor.
An Apollo-type orbit is the trajectory of a near-Earth asteroid (specifically an Apollo asteroid) whose orbital period is less than Earth's but whose aphelion extends beyond Earth's orbit, crossing Earth's path. Classified by the International Astronomical Union, these objects have semi-major axes greater than 1.0 AU and are known for potentially impacting Earth due to their Earth-crossing nature.
What this means in real life
When a spacecraft launches toward the Moon, it first circles Earth to gain speed, then fires its engines to break free and coast toward the Moon. Once there, it slows down to enter orbit around the Moon before firing again to head home—that entire journey is an Apollo-type orbit.
What it isn’t
This is not a single continuous circular orbit. It's a multi-phase trajectory involving Earth departure, lunar approach, orbital insertion, and return—not simply orbiting the Moon indefinitely or a direct point-to-point path.
Commonly misused online
People sometimes use it to mean any Moon mission or assume it requires the exact hardware Apollo used. In reality, it's a trajectory design that any spacecraft—crewed or robotic—can follow regardless of its construction.