What two conditions are necessary for either a solar or lunar eclipse?

Answer 1

The apparent angular size of the Moon depends on its location in its orbit; when the Moon is at perigee (closest to Earth) it is about 50,000 miles closer than at apogee. When it is at perigee, it looks a little bigger than the apparent angular diameter of the Sun, and we can get total eclipses. When the Moon is at apogee, the Moon appears to be a little SMALLER than the Sun, and during a solar eclipse the Moon doesn't QUITE cover the Sun, so we get a "ring" or "annular" eclipse.

Answer 2

1. the Moon must be in line with the Earth and Sun - New Moon for a solar eclipse and Full Moon for a lunar eclipse.2. the Moon must be at one of its nodes. Most of the time the Moon at New or Full passes above or below the Sun because its orbit is tilted relative to the ecliptic. An eclipse can occur only when it is at a node, in other words crossing the ecliptic.

Answer 3

The Moon needs to be exactly between your eyes and the Sun. This means that you are in the Moon's shadow.