C/2021 C4 ( ATLAS )

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Updated on December 22, 2025

Profile Discovery Date February 12, 2021 Magnitude 18.7 mag Discoverer Asteroid Terrestrial-Impact Last Alert System (ATLAS) search program Pictures

Orbital Elements Perturbed ephemeris below is based on elements from MPEC 2025-UQ3. Epoch (TT/JD) T (TT/JD) Peri. Node Incl. 2459240.50000 2459231.5093778 320.22692 194.27825 132.83989 e q a Epoch (TT) 0.9989448 4.5041559 4268.46471 2021/01/26.00

Magnitudes Graph m1 = 1.5 + 5 log d + 20.0 log r

The orbital elements are calculated using the Minor Planet & Comet Ephemeris Service. The magnitudes graphs are made with Comet for Windows.