Technically a “temporarily captured object,” 2024 PT5 is a near-Earth asteroid and Earth’s newest mini-moon. This 11-meter diameter near-Earth asteroid — about the same as a London bus — is expected to stay in orbit for a couple of months before resuming its own journey through the solar system on Nov. 25.

Near-Earth objects (NEOs) that move in horseshoe-shaped paths can come close to our planet at low speeds. During these times, they might experience “mini-moon” events, where their energy relative to Earth becomes negative. This means they can stay close to Earth for hours, days, or even months but won’t fully orbit the planet.