Asteroids Spinning Faster than Expected
Recent findings from a study conducted by Dmitrii Vavilov and his team at the University of Washington have revealed remarkable insights into the rotation of large asteroids. Analyzing over 9,000 asteroids using data from the Vera C. Rubin Observatory, they focused on 260 asteroids, measuring their rotation based on brightness changes caused by their irregular shapes.
Key Findings:
-
Super-Fast Rotators: Among the asteroids studied, 66 were identified as super-fast rotators, completing their spins in less than 2.2 hours. This rapid rotation exceeds the gravitational limits that should allow such bodies to remain intact.
-
Ultra-Fast Rotators: Two asteroids larger than 2 kilometers completed a full rotation every 5 minutes, a phenomenon previously unseen for such sizes. This indicates that they might not be loose “rubble piles” but rather solid objects.
-
Structural Insights: Vavilov suggests that these asteroids could be 30 times stronger than clay, challenging current models of asteroid collisions and formation throughout the solar system’s 4.6-billion-year history.
-
Surface Dynamics: If a person were standing on one of these rapidly spinning asteroids, they would experience conditions akin to a rollercoaster ride, with speeds exceeding 100 km/h.
-
YORP Effect: Their spinning may be influenced by the YORP effect, where solar heating causes torque, but the exact dynamics remain uncertain due to their distance from the sun.
This discovery opens new questions about the composition and formation of asteroids, suggesting some may be pristine remnants from the early solar system. Future studies will aim to investigate these intriguing celestial bodies further.
