Seasons & Moon Phases
Eclipses, Umbra, Penumbra
Earth’s OrbitDecember 21
Winter Solstice
March 21
Vernal Equinox
September 23
Autumnal Equinox
June 21
Summer Solstice
Northern Hemisphere Winter
• When the pole slants away from the sun, the Northern Hemisphere receives the least sunlight and it is winter.
Summer, Spring, Autumn• Spring begins when the pole starts to
slant toward the sun, and autumn begins when the pole starts to slant away again.
• When the North Pole slants toward the sun, the Northern Hemisphere receives the most sunlight and it is summer there.
Ecliptic
Analemma
Phases of the Moon
• New Moon• Waxing Crescent• First Quarter• Waxing Gibbous• Full Moon• Waning Gibbous• Last Quarter• Waning Crescent• Moon Phase Applet• Moon Phase Calcul
ator
New Moon
Waxing Crescent
First Quarter
Waxing Gibbous
Full Moon
Waning Gibbous
Last Quarter
•Waning Crescent
Moon’s Orbit is Tilted
Solar Eclipse
Umbra to Penumbra