Simplify the following text for a Grade 6 native English-speaking person.
Original: Pickering attempted to compute an orbit , which showed a fairly high inclination ( 39.1 Â to the ecliptic ) , fairly large eccentricity ( 0.23 ) and a semi-major axis ( 1,457,000 km ) slightly less than that of Hyperion .
Simplified: He thought that Themis had an inclination of 39.1 Â to the ecliptic , with 0.23 eccentricity ( 0.23 ) and a semi-major axis distance of 1,457,000 km .