Peel the beets, and cut them into wedges. Place beets in a large saucepan, and cover with water. Boil. Reduce heat, and simmer for 15 minutes, or until tender; drain. Finely grate 2 teaspoons orange rind. Peel and section the oranges, reserving 2 tablespoons juice. Combine orange rind, juice, olive oil, and a pinch each of salt and pepper. Place 1/2 cup arugula on each of 4 plates. Divide beets and orange sections among the plates, and drizzle with dressing. Top each serving with 1 tablespoon ricotta; sprinkle with caraway seeds.