The Earth’s TiltThe Earth’s Tilt

The Earth’s TiltThe Earth’s Tilt The Earth is tilted on The Earth is tilted on

its axis at 23.5 its axis at 23.5 degreesdegrees

For 6 months the For 6 months the Northern Hemisphere Northern Hemisphere is tilted towards the is tilted towards the sun and for the next 6 sun and for the next 6 months the Southern months the Southern Hemisphere is tilted Hemisphere is tilted towards the suntowards the sun

This is the cause for This is the cause for the seasonsthe seasons

Solstices/EquinoxSolstices/Equinox Summer Solstice-June 22nd, Maximum Summer Solstice-June 22nd, Maximum

amount of daylight for the Northern amount of daylight for the Northern HemisphereHemisphere

Autumnal Equinox-September 22Autumnal Equinox-September 22stst, Equal , Equal amount of sunlight for both Hemispheresamount of sunlight for both Hemispheres

Winter Solstice-December 22Winter Solstice-December 22stst, Maximum , Maximum amount of daylight for the Southern amount of daylight for the Southern HemisphereHemisphere

Vernal Equinox-March 22Vernal Equinox-March 22stst, Equal , Equal amount of sunlight for both Hemispheresamount of sunlight for both Hemispheres

Precession Precession

Precession is the Precession is the change in the change in the orientation of a orientation of a rotating axisrotating axis The angle remains The angle remains

constant but the constant but the direction of the axis direction of the axis changeschanges

Would not affect Would not affect Earth’s Seasons but Earth’s Seasons but would affect what would affect what stars are seen at nightstars are seen at night

Nutation Nutation

Nutation is the Nutation is the wobbling that wobbling that occurs around occurs around Earth’s axis which Earth’s axis which changes the angle changes the angle about ½ of a about ½ of a degree every 18 degree every 18 yearsyears Happens due to the Happens due to the

gravitational pull of gravitational pull of the moonthe moon

BarycenterBarycenter

A barycenter is the A barycenter is the center that 2 center that 2 objects orbit objects orbit around. around. When the moon When the moon

orbits a planet both orbits a planet both bodies orbit around bodies orbit around a point in the a point in the middle middle

This point is closer This point is closer to the larger bodyto the larger body

BarycenterBarycenter

The sun does not The sun does not remain motionless remain motionless in the solar in the solar system. system. Due to the pull of Due to the pull of

the planet’s gravity the planet’s gravity the sun orbits a the sun orbits a barycenter in the barycenter in the solar system solar system