Early Observations of New Active Asteroid 2025 VZ ₈

Abstract We report observations of main-belt asteroid 2025 VZ 8 using multiple telescopes from UT 2025 November 24 to UT 2025 December 23 that confirm the presence of visible comet-like activity. These observations were motivated by online reports that an abrupt brightening event may have led to the object’s discovery on UT 2025 November 9. In all observations reported here, the object displays a tapered tail approximately 3″ long aligned with the antisolar direction. The object has an asteroidal Tisserand parameter value with respect to Jupiter ( T J = 3.371), and is thus considered an active asteroid. We measure an average apparent <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mi>r</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>′</mml:mo> </mml:mrow> </mml:msup> </mml:math> -band magnitude of m r ∼ 21.6 mag over the reported observing period. Due to the sudden appearance of activity far from perihelion, we suggest that the activity is more likely due to an impact or rotational destabilization, rather than sublimation.