NASA has made a shocking update on Earth’s nearest rocky neighbor: there is now more than one Moon orbiting our planet! But don’t worry –Earth won’t have two moons for too long. This second “moon” is officially known as “2025 PN7.”
2025 PN7 was first discovered by observers with Pan-STARRS in Hawaii who in turn added it to an official ledger that tracks new minor planets. Managed by the Minor Planet Center in Cambridge, Massachusetts, this center manages a master list of asteroid observations and orbit confirmations, validating discoveries like the one in Hawaii, and publishing the orbital math that allows scientists and their telescopes to track objects in space.
Pan-STARRS is short for “Panoramic Survey Telescope and Rapid Response System; it’s a ground based telescope project in Hawaii that performs large-scale sky surveys to find and track moving objects in our solar system. The first telescope in the project, PS1, is a 1.8-meter telescope on the summit of Haleakalā on Maui. The Pan-STARRS Project is a collaboration between the University of Hawaiʻi Institute for Astronomy, MIT Lincoln Laboratory, Maui High Performance Computing Center and Science Applications International Corporation. Telescope construction was funded by the U.S. Air Force. Construction of Pan-STARRS was funded in large part by the U.S. Air Force Research Laboratory with additional funding to complete Pan-STARRS2 came from the NASA Near Earth Object Observation Program, which also supplies most of the funding to operate the telescopes.
But unlike -the- Moon that everyone is familiar with in Earth’s night sky, 2025 PN7 will only be a temporary visitor. 2025 PN7 is a tiny quasi-moon that’s about 36 meters wide, roughly the height of a small building. This asteroid will travel nearly in sync with the Earth for many years, keeping pace with the Earth and looping around the Sun in a path so similar that it appears to shadow Earth as we orbit it. Unlike the Moon which is held tight by gravity, 2025 PN7 isn’t bound to Earth and will eventually move away. Astronomers say 2025 PN7 has likely been circling the Earth for the last 60 years and should continue to do so for the next 58 years. In 2083, the asteroid’s orbit is expected to become out of synch with the Moon and the Earth and appear in the sky as if it’s moving away.
While 2025 PN 7 will make for an unusual neighbor for the decades ahead, it isn’t a threat to Earth. NASA scientists say it should move away as harmlessly as it arrived.
