Orbital Mechanics HW – MET 213 1 – What is the orbital period for a satellite 385,000 km from Earth? How does it compare to the period of the moon orbiting around the Earth? Distance is measured from the center of the Earth
2 – What is the orbital period for a body orbiting the Sun at a distance of 149,600,000 km? How does that compare to one Earth year? Distance is measured from the center of the Sun
3 – Halley’s comet travels on a very elliptical path whose minimum distance from the Sun is 0.586 AU, where 1 AU = 1 Astronomical Unit = Average distance from the center of the Earth to the center of the
Sun. 1 AU=149,600,000 km. The comet’s max distance form the center of the Sun is 35.1 AU. Find: a)
b)
c)
d)
Velocity at closest approach to the Sun, called perihelion
Velocity at farthest distance from the Sun, called aphelion
Orbital period, in seconds and in years
Escape velocity from the Sun at perihelion
4 – The Apollo command‐service module (CSM) traveled in an orbit whose farthest distance from the surface of the Moon was 310 km. Its closest approach was 110km above the surface of the Moon. After the CSM was placed in the elliptical (310km x 110km) orbit around the Moon, the orbit was circularized to 110 km above the surface. Find: a)
b)
c)
d)
The period of the elliptical orbit
The period of the circular orbit
Velocity of the CSM in the circular orbit
How does the velocity in the circular orbit compare to the velocity in the elliptical orbit at the
minimum height of 110 km above the surface?
Apollo Command‐Service Module