The Sun is 400X larger than the Moon, it is also 400X farther away from Earth than the moon. For this reason, the Moon/Sun appear to be the same size in the sky.
Since the Moon and Sun appear to be the same size, the Moon completely covers the Sun during a total solar eclipse, leaving only the corona, the outer atmosphere of the Sun visible. Total eclipses last from a few seconds to just over 7 min. They occur once every 2 years somewhere on the Earth. During solar eclipse, astronomers can safely study solar flares. Partial/annular eclipses occur when the Moon does not cover the entire disk of the Sun.
– Solar Eclipse: Results during a new moon, when the Moon, at one of its nodes, is directly between Earth and the Sun.
A total lunar eclipse results when the entire Moon passes through Earth’s shadow. If only parts of the Moon passes through Earth’s shadow, there is a partial lunar eclipse. During a total lunar eclipse, the Moon is barely visible since it is hidden in Earth’s shadow. Sunlight is bent by Earth’s atmosphere onto the Moon. The light is red for the same reason that the sunset is red: the shorter (bluer) wavelengths are scattered away by Earth’s atmosphere, leaving longer (redder) wavelength light to shine on the Moon.
– Lunar Eclipse: Results when Earth is positioned between the Sun and the Moon such that Earth casts its shadow on the surface of the Moon; the Moon must be at a node.
Review Videos
Interactive Lab
Try this Interactive Lab to “create” your own eclipse. Along with the lab, there are review questions on the web link you can try out 😉 .
Clinton's Astronomy Blog 