Solar Eclipses What exactly is a solar eclipse

Solar Eclipses

What exactly is a solar eclipse? • What is an eclipse? • What causes eclipses and why? • How often do eclipses happen?

Phases of the Moon • The Moon is a celestial body/natural satellite that orbits Earth • The Moon does not produce its own light but reflects the Sun’s light • The Moon orbits Earth about every 29. 5 days • As it circles the Earth, the changing position of the Moon with respect to the Sun causes the moon to appear in different “phases”

The Moon’s Two Shadows • A solar eclipse can only occur during New Moon phase • If the Moon’s shadow happens to fall upon Earth’s surface during this time, there could be a portion of the Sun covered by the moon • Even though a New Moon phase occurs every 29. 5 days, we don’t have a monthly solar eclipse because the Moon’s orbit is tilted 5 degrees • At least twice a year, the geometry lines up just right for an eclipse for part of Earth

The Moon’s Two Shadows • The Moon has two different parts to its shadow • 1) Penumbra – faint outer shadow; partial solar eclipses visible • 2) Umbra – dark inner shadow; total solar eclipses visible • When the penumbral shadow strikes Earth, we see a partial eclipse

Total Solar Eclipses • If the Moon’s inner (umbral) shadow sweeps across Earth, a total eclipse can be seen • The path the inner shadow moves across Earth is called the Path of Totality • The path is only about 100 miles wide • To see a total eclipse, one must be inside the path • It’s very rare to see a total solar eclipse twice in one place • Ex: Princeton, NJ had a total solar eclipse in 1478. Next one will be 2079!

Totality • The total phase of a solar eclipse is very brief, usually only a few minutes • During totality, the corona can be seen (ring around the Sun)

Annular Solar Eclipses • Not every solar eclipse is a total eclipse • Because of the elliptical (oval) shape of the Moon’s orbit, the Moon is sometimes too far away to completely cover the Sun in the sky • When this happens, the Moon appears smaller and leaves a larger ring around the edge. • This type of eclipse is called an Annular Solar Eclipse • Annularity can last as long as a dozen minutes

Works Cited • "Espenak, Fred. “Solar Eclipses for Beginners. ” Mr. Eclipse. com, http: //www. mreclipse. com/Special/SEprimer. html. Accessed 10 August 2017.