PHASES OF THE MOON PHASES OF THE MOON & ECLIPSES& ECLIPSES

PHASES OF THE MOONPHASES OF THE MOON

• The lunar cycle is approximately 29.5 days in length.

• The appearance of the Moon during the different phases is a result of the position of the Earth and the Moon with respect to the Sun.

http://upload.wikimedia.org/wikipedia/en/7/72/Lunar-Phase-Diagram.png

The Appearance of the The Appearance of the MoonMoon

• When the Sun and Moon are aligned on the same side of the Earth, the Moon is “NEW", and is not illuminated by the Sun

• When the Moon is getting fuller (progressing from new to full) it is WAXING

•When the Sun and the Moon are aligned on opposite sides of the Earth, the moon is “FULL” and one side is fully illuminated by the Sun

•When the Moon is shrinking (progressing from full to new) it is WANING

The Appearance of the The Appearance of the MoonMoon

Lunar Phases Tutorial

LUNAR ECLIPSESLUNAR ECLIPSES

• A Lunar Eclipse occurs whenever the Moon passes through some portion of the Earth’s shadow.

• This can only occur when the Earth, the Moon and the Sun are aligned with the Earth in the middle.

• Therefore, the Moon is always Full during a lunar eclipse.

LUNAR ECLIPSESLUNAR ECLIPSES

• Why is it that there is not a lunar eclipse every month?– The orbital plane of the moon is

about 5 higher than the orbital plane of the Earth.

– During most months, the Moon is either north or south of the Earth during the full Moon.

LUNAR ECLIPSESLUNAR ECLIPSES

• The Earth’s shadow has two parts:– The UMBRA (no direct

solar radiation)– The PENUMBRA (solar

radiation is partially blocked)

• Depending on the location of the moon, different types of eclipses may be seen.

LUNAR ECLIPSESLUNAR ECLIPSES

• Partial Penumbral Eclipse – Occurs when the Moon passes into

the penumbra– No distinct changes are seen, but

the moon may appear more yellow

• Total Penumbral Eclipse– Very rare; Occurs when the Moon

passes fully into the penumbra

LUNAR ECLIPSESLUNAR ECLIPSES• Partial Lunar Eclipse

– Occurs when only a portion of the visible Moon enters the Earth’s umbra

• Total Lunar Eclipse– Occurs when the Moon is fully

obscured for a period of time by the Earth’s umbra

– The length of the eclipse may vary depending on the proximity of the Moon to its APOGEE (farthest distance from Earth)

TOTAL LUNAR ECLIPSETOTAL LUNAR ECLIPSE

SOLAR ECLIPSESSOLAR ECLIPSES

• A Solar Eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partially obscuring Earth's view of the Sun.

• This only occurs during the New Moon phase of the Lunar Cycle, when the Sun and the Moon are aligned on the same side of the Earth.

SOLAR ECLIPSESSOLAR ECLIPSES

• TOTAL ECLIPSE– Very rare– The Sun is totally

obscured by the Moon

– The CORONA is visible during this time

– Only visible from a specific location on the Earth

SOLAR ECLIPSESSOLAR ECLIPSES

• ANNULAR ECLIPSE– The Sun and Moon

are directly in line, but the apparent size of the Moon is smaller than the Sun, leaving a ring, or ANNULUS.

SOLAR ECLIPSESSOLAR ECLIPSES

• HYBRID ECLIPSE– Intermediate between a Total and Annular

eclipse– Rather rare

• PARTIAL ECLIPSE– The Moon and Sun are not completely in

line– Can usually be seen from many places on

Earth when a specific place is seeing an Annular or Total eclipse

OTHER LUNE-Y STUFFOTHER LUNE-Y STUFF• BLUE MOON

– The trendy definition is not true! A Blue Moon is NOT the second full Moon in a month!

– It has historically been determined as the 13th full Moon of a year (there are normally 12 full moons)

– There have been instances of the Moon actually turning blue (when a volcano in Indonesia erupted).

OTHER LUNE-Y STUFFOTHER LUNE-Y STUFF• HARVEST MOONHARVEST MOON

– The Full Moon that occurs closest to the Autumnal Equinox.

– It is a myth that it appears with a red, orange or yellowish tinge.• Any moon or constellation lower on the horizon

appears to have a reddish tinge because the light coming from it is traveling through more atmosphere.

– It is also thought that a harvest moon is larger in the sky…• But any full moon seen closer to the horizon appears

larger than a moon higher in the sky (called a Moon Illusion)

OTHER LUNE-Y STUFFOTHER LUNE-Y STUFF• THE MAN IN THE MOON

– The "Man in the Moon" is a figure resembling a human face.

– The figure is composed of large dark areas (the lunar maria, or seas) on the Moon's surface.

– The figure's eyes are the Mare Imbrium and Mare Serenitatis, its nose is the Sinus Aestuum, and its open mouth is the Mare Nubium and Mare Cognitum.

The Face of a Woman

A Rabbit