Answer:
'The Second Largest known Asteroid according to it's mass is 4 Vesta or simply Vesta'. It comprises about 9% of the mass of the entire Asteroid Belt. It has a mass of (2.67 ± 0.02) × 1020 kg. It has a mean diameter of about 530 km. It is 'The Second most Massive object in the Asteroid Belt'. Vesta was discovered by the German Astronomer, Heinrich Wilhelm Olbers on March 29, 1807. Vesta is also 'The Brigthest Asteroid'.
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