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Keywords from Image Description:
The Four Largest Asteroids. en These are the four largest asteroids known as The Big Four were shown on the picture Ceres km Vesta km Pallas km Hygiea km File PIACeresDwarfPlanetDawnRCimage File Vesta full mosaic File PallasHST File Hygiea Lightcurve Inversion Ceres and Vesta images NASA Pallas image Hubble Space Telescope