C/2025 K4 ( Siverd )

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Updated on October 5, 2025

Profile Discovery Date May 30, 2025 Magnitude 19.1 mag Discoverer Robert Siverd (Asteroid Terrestrial-Impact Last Alert System (ATLAS) search program)

Orbital Elements Epoch 2025 Nov. 21.0 TT = JDT 2461000.5 T 2025 July 28.23274 TT Pike q 2.5320802 (2000.0) P Q z +0.0231414 Peri. 326.92308 +0.00146237 +0.83200860 +/-0.0001085 Node 297.08463 -0.72753329 -0.37972082 e 0.9414042 Incl. 38.54230 -0.68607082 +0.40444256 From 27 observations 2025 May 30-Aug. 15, mean residual 0".5.

Magnitudes Graph m1 = 12.5 + 5 log d + 10.0 log r

The orbital elements are published on M.P.E.C. 2025-R69. The magnitudes graphs are made with Comet for Windows.