He leaned forward and studied the planet below as the ship's orbit brought them over the area of sunrise.
Its orbit brings it 30,000 km closer to Earth every 15 years.
For a comet, the stress occurs when its orbit brings it close to the Sun.
The asteroid's orbit must periodically bring it near the Earth.
"How close will their orbits bring them to the earth?"
This orbit will bring the star closer to the Solar System in the future.
When the next orbit of the Apollo spacecraft brought it overhead he turned on the cabin transmitter and sent up a call.
Such an orbit would bring the planet near the rest of the Solar System only every 700 to 1,000 years, he said.
It glinted in the light of the yellow sun as its orbit brought it from behind the world.
Its 560-year elliptical orbit brings it as close as 3.3 billion miles.