Overview
- Closest approach occurs around 1 a.m. ET on December 19 at roughly 1.8 AU from Earth (about 167–170 million miles), with no impact risk, according to NASA/JPL.
- Skywatchers can look before dawn near Regulus in Leo using binoculars or a small telescope, or watch a Virtual Telescope Project livestream starting 11 p.m. ET on December 18.
- A coordinated campaign using Hubble, JWST, SPHEREx, Psyche, Lucy, MRO and MAVEN is collecting multi‑wavelength images and spectra during the flyby.
- Precision tracking reports non‑gravitational acceleration consistent with outgassing, which researchers describe as typical comet behavior.
- Spectra suggest elevated CO2 relative to water; Hubble limits the nucleus to roughly 1,000 feet to 3.5 miles across, and the object is bound for a Jupiter‑region pass in 2026 before exiting the solar system.