Simplify the following text for a Grade 10 native English-speaking person.
Original: is about 1 kilometre in diameter , and orbits Jupiter at an average distance of 17,883 Mm in 489.72 days , at an inclination of 143 Â to the ecliptic ( 143 Â to Jupiter 's equator ) , in a retrograde direction and with an eccentricity of 0.4920 .
Simplified: is about 1 kilometre in diameter , and orbits Jupiter at an average distance of 17,740,000 km in 482.691 days , at an inclination of 143 Â to the ecliptic ( 143 Â to Jupiter 's equator ) , with an eccentricity of 0.4449 .