2 Moons In September 2025. From september 29 to november 25, earth will temporarily gain a second moon, 2025 pt5, a tiny asteroid measuring about 10 meters. It occurs around the autumn equinox and is famous for rising right after sunset for several days in a row.

Here’s what the experts have said. In just over one week’s time, earth will gain a new celestial companion that will stay for two months in the planet’s gravitational cradle.