Asteroids, with their varied shapes and sizes, are fascinating objects of the solar system. Their shapes are largely dictated by gravitational forces, with larger asteroids having enough gravity to form into roundish objects. These space rocks are riddled with craters due to many collisions over time. Among them, Ceres stands out as the largest, with a diameter just under 1000 kilometers, about one-fourth that of the Moon. It’s believed that over a million asteroids have diameters exceeding 1 kilometer. To estimate an asteroid’s size, astronomers measure its brightness, which varies based on its size, distance from Earth, and reflectivity. Brightness helps determine size: the brighter the asteroid, the larger it is, assuming equal distance from Earth. This distance is measured by tracking the asteroid’s orbital position, while reflectivity is gauged by comparing the light it reflects from the Sun to its infrared emission, indicating its temperature.
Sources: Ceres (photo)
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