Star Gazers – Earth is about to gain a second “moon,” though it won’t stay for long.
According to a study published in the Research Notes of the American Astronomical Society, this second moon, known as 2024 PT5, is a celestial body believed to be an Arjuna asteroid. These asteroids are “minor bodies moving in orbits with low eccentricity, low inclination, and Earth-like periods.” Notably, this isn’t the first time Earth has had a “mini-moon.”
The study explains, “Near-Earth objects that follow horseshoe paths and approach our planet at close range and low relative velocity may undergo mini-moon events, during which their geocentric energy becomes negative for hours, days, or months—though without completing one revolution around Earth while bound.” An example is 2022 NX1, a near-Earth object that experienced a brief mini-moon event in 1981 and again in 2022.
While short mini-moon events are relatively common, longer capture episodes are rare, occurring only about once every 10 to 20 years. Stargazers will need a telescope to catch a glimpse of this mini-moon, as it is too small to be seen with the naked eye.
Researchers estimate that the mini-moon will appear on September 29 and remain in Earth’s orbit until around November 25.