Transcript Tides & Eclipses

Tides & Eclipses
By: Kiah Bransch, Iva Rreza, Ashley
Pantona-Price, and Gabby Jones
Universal forces
Albert Einstein, the
renowned physicist and
philosopher, summed up
the universe forces into
four main forces known
as electromagnetic,
gravitational, and the
weak and strong forces
within an atom. While
gravity and
electromagnetic are
infinite, the forces within
an atom are finite.
Electromagnetism is a
force that occurs
wherever magnetic and
electric field occur.
The elementary particles of
the universe are known as
quarks where the weak
forces cause radiation and
the strong forces bind
matter together.
Gravity is also an infinite
force and a centripetal
force that happens when
an object is massive
enough. When this is true
an object constantly
attracts objects towards
it.
Days, Years, and Seasons
• While the earth is constantly
kept into orbit through
gravity, the earth experiences
temperature changes as it
rotates and revolves.
• Since the earth is somewhat
of a sphere, it receives
different amounts of light
throughout. (more at equator
than at poles)
• The constant revolution
causes earth to have period
of light and no light which
occurs every 23 hours and 56
minutes.
• Since earth’s orbit is not a
perfect circle earth’s
temperature changes due to
distance.
• Seasons are caused by the tilt
of the earth’ s axis (23.5º) as
it orbits the sun.
• The measure of one year is
equal to the time it takes the
earth to make one full
revolution.
• Since the distance from the
sun changes, earth’s speed
changes, speeding when near
the sun, and slowing down
when farther.
Solar Eclipses
The first is called a solar eclipse, and it is
caused by the moon’s shadow falling
on the earth.
This occurs only when the moon is
directly in front of the earth.
The amount of light that is blocked by
the moon’s shadow differs because
the moon is significantly smaller than
the earth.
The umbra is the portion of the shadow
where most light is blocked and
produces a total solar eclipse.
The portion of the earth that is covered
by the penumbra, or the portion of the
shadow that blocks only a part of the
sun’s light, experiences a partial solar
eclipse.
The second kind of eclipse is a lunar
eclipse. This is when the earth’s
shadow falls on the moon. This
kind of eclipse can only be seen
during a full moon.
Lunar Eclipses
During this time the moon is moving
at 1 km per second.
Lunar eclipses are observed more
often than solar because the earth
is significantly bigger than the
moon so the moon is always
covered by earth’s umbra.
Even though the moon is tilted 5º in
relation to the alignment of the
sun, moon, and earth, it
eventually passes directly behind
the earth.
Lunar eclipses can be observed by
the naked eye.
Tides
• Earth’s oceans go through constant flux in
phenomenon known as tides.
• Caused by the pull of the moon’s gravity on
earth’s oceans.
• Earth’s oceans are balanced by centrifugal force
which counteracts centripetal force of earth’s
gravity.
• The place nearest the moon always has the highest
tide and since the earth is constantly spinning,
there is a high tide on the opposite side too. The
positions in between experiences low tides.
• Tides constantly vary from time to time and
position to position.
Spring Tides
• Tides occur in different
positions and alignments.
• Spring tides occur when the
moon, earth, and sun are
aligned.
• As the moon orbits around the
earth, the oceans bulge
outward.
• The greatest difference between
high and low tide is known as a
spring tide.
• Spring tides can only occur
during full and new moon.
• The position that is closest to
the moon and the one opposite
to it experiences the highest
tide and the same is for lowest
tide.
• When the position of the moon
in relation to the earth and sun
is at a 90º angle, a neap tide,
occurs.
• This occurs when the sun,
earth, and moon are not
aligned and the gravitational
forces cancel each other out.
• This tide is also known as the
smallest difference between
high and low tide.
• Neap tides occur twice in a
month during the first and last
quarter.
Neap Tides
Moon phases
• The infinite force that keeps the earth orbiting
around the sun also keeps the moon orbiting the
earth.
• Since the moon is an illuminated object, the
portion that is “lighted up” always changes.
Orbiting and rotational period: 27.3 earth days.
Moon phases in chronological order: New moon,
waxing crescent, first quarter, waxing gibbous, full
moon, waning gibbous, last quarter, waning
crescent, and then back to a new moon.