A 42 kg ( 56 pounds ) 30 - centimetre - diameter ( 0.98 ft ) metal payload sphere floated .
Was free to rotate in a liquid freon reservoir contained in the landing sphere .
A 42 kg ( 56 pounds ) 30 - centimetre - diameter ( 0.98 ft ) metal payload sphere floated and was free to rotate in a liquid freon reservoir contained in the landing sphere .