... Re denotes Earth radius. ... You note that the Earth orbits around the Sun in a counterclockwise direction. ... 7] In one of the eclipses of 1999 the Moon is unable to cover the entire Sun. ... Take the radius of the Earth's orbit as 300 million km, the velocity of light as 300,000 km/sec. ... 10] Section #8b, about using a total solar eclipse to estimate the distance of the Moon, includes a map of the eclipse of August 11, 1999. ... A spaceship has just enough velocity to escape the Earth's gravity...

... You note that the Earth orbits around the Sun in a counterclockwise direction. ... 7] In one of the eclipses of 1999 the Moon is unable to cover the entire Sun. ... If an object were to be placed in the Earth orbit but with no velocity relative to the Sun, it would fall sunward. ... You may assume that the width of the Earth is 3.5 times that of the Moon (see problem 15), that the Moon is 60 Earth radii from the center of Earth and that, as seen from Earth, it is equal in size to the Sun. ...

Educator's Guide to Eclipses . ... In a solar eclipse you observe the Sun (using only safe methods, of course). ... In a lunar eclipse you observe the Moon. ... Because of the geometry described below, you can only view a solar eclipse when the Sun is up, and the Moon is nowhere to be seen. ... Eclipses occur when the Sun, Earth and Moon line up. ... In a solar eclipse the Moon passes directly in front of the Sun. ... In a lunar eclipse the Moon moves into Earth's shadow. ...