Download Distance from the Sun

Distance from the Sun
1 Astronomical Unit = 149, 597, 871 kilometers
Average Distance from the Earth to
the Moon: 221,567 miles
Average Distance from the Earth to the Sun:
93,020,000 miles (149, 597, 871km )(1 AU)
DID YOU KNOW THE MOON CAUSES
TIDES????
What are tides?
• Tides are periodic rise and fall of large bodies of water.
• Tides are caused by the gravitational interaction
between the Earth and the Moon.
• The gravitational attraction of the moon causes the
oceans to bulge out in the direction of the moon.
• Another bulge occurs on the opposite side, since the
Earth is also being pulled toward the moon (and away
from the water on the far side).
• Since the Earth is rotating while this is happening, two
tides occur each day.
• Spring tides are especially strong tides (they do not have
anything to do with the season Spring).
• They occur when the Earth, the Sun, and the Moon are in a
line.
• The gravitational forces of the Moon and the Sun both
contribute to the tides.
• Spring tides occur during the full moon and the new moon.
• Neap tides are especially weak tides.
• They occur when the gravitational forces of the
Moon and the Sun are perpendicular to one
another (with respect to the Earth).
• Neap tides occur during quarter moons.
What causes Earth’s seasons?
• The Earth's axis of rotation is tilted in relation
to the ecliptic plane, an imaginary surface
through Earth's orbit around the sun.
• This means the northern and southern
hemispheres will sometimes point toward or
away from the sun depending on the time of
year, varying the amount of light they receive
and causing the seasons.
Tilt of the Earth’s axis towards or away from
the sun creates the seasons
When the north pole tilts toward the
sun, it gets more radiation – more warmth
during the summer
When the north pole tilts toward the
sun, the south pole tilts away
So when it’s summer in the north,
it’s winter in the south
SUMMER (Northern Hemisphere)
WINTER (Southern Hemisphere)
Tilt of the Earth’s axis towards or away from
the sun creates the seasons
When the north pole tilts away
from the sun, it gets less radiation –
So it’s colder during the winter
When the north pole tilts away from the
sun, the south pole tilts toward it…
When it’s winter in the north,
it’s summer in the south
WINTER (Northern Hemisphere)
SUMMER (Southern Hemisphere)
Does the Moon have seasons?
• The tilt of Earth's axis is about 23.5 degrees,
but the tilt of the moon's axis is only about 1.5
degrees.
• As such, the moon virtually has no seasons.
• This means that some areas are always lit by
sunlight, and other places are perpetually
draped in shadow.
Videos
What is a Solstice?
• At two points throughout the year, the tilt of the
Earth’s axis reaches its maximum angle compared to
the Sun, and begins to move back the other direction.
• This usually happens around June 21st and December
21st. These days are known as solstices.
• On these solstices, the rays of the Sun shine directly on
one of the two Tropics.
• During the June Solstice the rays of the Sun shine
directly on the Tropic of Cancer. During the December
Solstice the Sun’s rays shine on the Tropic of Capricorn.
Solstice
June 21st
December 21st
What is an Equinox
•As the Earth moves around its orbit, it reaches
two points during the year where the tilt of its
axis causes it to be straight relative to the Sun.
•These days are known as equinoxes. During
these equinoxes the rays of the Sun shine
directly on the equator.
• This happens on approximately March 20th
and September 22nd.
Equinox
March 20th and September 22nd
Worksheet
Vocabulary to know!
• Ellipse- A closed, symmetric curve shaped like
an oval. Earth’s shape is nearly circular!
• Tilt- to cause to lean, incline, slope, or slant.
Clementine’s Contributions
• Clementine's four cameras took more than 2 million pictures
of the moon.
• A laser device measured the height and depth of mountains,
craters, and other features.
• Radar signals that Clementine bounced off the moon
provided evidence of a large deposit of frozen water.
• The ice appeared to be inside craters at the south pole.
• Another kind of information collected by the Clementine
Spacecraft indicates what kinds of minerals make up moon
rocks.
• Clementine Space Craft got its name after the song, "Oh my
darling Clementine." The song has a line ' Thou art lost and
gone forever' - a reference to its one-way journey with no
return.
Phases of the Moon
Lunar vs. Solar Eclipse
• A lunar eclipse occurs when the Earth passes
between the Moon and the Sun, and the
Earth's shadow obscures the moon or a
portion of it.
• A solar eclipse occurs when the Moon passes
between the Earth and the Sun, blocking all or
a portion of the Sun.
Terms to know….
• Umbra-The completely dark portion of the
shadow cast by the earth, moon, or other
body during an eclipse.
• Penumbra-A partial shadow, as in an eclipse,
between regions of complete shadow and
complete illumination.
Lunar Eclipse
Lunar Eclipse
• A lunar eclipse occurs when the Moon passes
directly behind the Earth into its umbra
(shadow).
• This can occur only when the Sun, Earth, and
Moon are aligned exactly, or very closely so,
with the Earth in the middle.
Solar Eclipse
Solar Eclipse
• As seen from the Earth, a solar eclipse occurs
when the Moon passes between the Sun and
Earth, and the Moon fully or partially blocks
the Sun.
• This can happen only at the new moon phase.
Lunar Eclipse
Solar Eclipse
Why doesn’t a solar eclipse and a lunar
eclipse occur every month?
• Solar and lunar eclipses don't occur every month
because the plane of the Moon's orbit around the
Earth is not aligned with the plane of the Earth's
orbit around the Sun.
• The Moon's path is tilted when compared to the
plane of Earth's orbit, so the Moon is not in a direct
line with the Sun and Earth.
• In a solar eclipse, the Moon must be directly
between the Sun and the Earth.
• Similarly, in a lunar eclipse (slightly more frequent),
the shadow of the Earth has to fall on the Moon.
Videos
Can you remember….
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What is a neap tide?
What is a spring tide?
What is an Equinox?
What is a Solstice?
What is a lunar eclipse?
What is a solar eclipse?
What does AU stand for?
• Comet- A celestial object consisting of a nucleus of ice and
dust and when near the sun, a “tail” of gas and dust points
away from the sun.
• Meteoroid- A meteoroid is a small rock or particle of debris in
our solar system. They range in size from dust to around 10
meters in diameter (larger objects are usually referred to as
asteroids).
• Meteor- A meteoroid that burns up as it passes through the
Earth’s atmosphere is known as a meteor. If you’ve ever
looked up at the sky at night and seen a streak of light or
‘shooting star’ what you are actually seeing is a meteor.
• Meteorite- A meteoroid that survives falling through the
Earth’s atmosphere and colliding with the Earth’s surface is
known as a meteorite.
• Asteroid- A small rocky body orbiting the Sun. Large numbers
of these, ranging in size from nearly 600 miles (1,000 km)
across to dust particles, are found between the orbits of Mars
and Jupiter.
Comets
• Object made of ice, gas, and dust that travels through
space.
• “solar system leftovers” possibly formed at the same time
as the sun & planets (4.5 billion years ago)
• Travel across the sky SLOWLY.
• Example: Halley’s Comet
• Travels towards the sun every 75-79 years… said to return
in 2062.
• Reflects Sunlight
Where do they come from?
Oort Cloud (vast collection of ice/dust) outside Pluto
More than a light year away from the sun (15 tril km)
Comets
Meteoroid
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Smaller than asteroids
Rocky – made of metal or stone
Orbit sun, outside Earth’s atmosphere
Believed to come from the Asteroid belt
Meteors
• We call them shooting stars
• They are meteoroids that enter Earth’s
atmosphere and burn up (streaks of light)
• The streak of light produced by a burning
metor
• Meteor shower – meteors coming from the
same place
• Meteor storm – many meteors
Meteor
Meteorite
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A meteor that strikes Earth’s surface.
Can land on other places, like the moon
Composed of iron, nickel, stone
Large meteorites have produced craters when
they hit Earth. (SW Africa, Canada, Arizona,
Russia)
Video
Meteorite
Asteroids
• Rocky, cratered bodies that orbit the sun
• Smaller than planets but larger than
meteoroids
• Reflects Sunlight
Meteor Shower April 21st-22nd!!!!!
• The Lyrid meteor shower should give sky
watchers in darkened parts of the world a
decent show late Sunday night (April 21) and
early Monday morning (April 22), but the glare
from a nearly full moon will probably impede
the view for many stargazers.
• "Moonlight will interfere with this year's
display, but away from city lights, you might
see up to 20 meteors per hour."
• What is the difference between comets and
meteors?
• What is the difference between a meteor,
meteorite, and meteoroid?
• What is an asteroid?
HOMEWORK!
Meteors
Known as shooting stars
Most found in the asteroid
belt
Asteroids
Object made of ice,
gas, and dust
Comets
What is a Star?
• A star is a huge
sphere of very hot
glowing gas.
• When stars are
grouped together we
call them
constellations.
• The Big Dipper is a
constellation that we
see often.
The Sun
• The Sun is the only star in our solar system.
– All eight planets, comets, and an asteroid belt,
revolve around the Sun.
– The Sun is a yellow, medium sized star.
Classyfiying Stars
• Stars are classified according to their
temperature and brightness.
• Hot stars are blue or white.
• Cooler stars are red or orange.
H.R Diagram
Classifying Stars Cont….
• A young star is called a dwarf star
– They can be colored red, yellow, or white.
– Our sun is a yellow dwarf.
• Older stars are called Super giants.
-They can be colored red or blue.
Copy this in your notes!
Life Cycle of a Star
• Our Sun is an average star. The chart below
shows the lifecycle of our sun over billions of
years.
How are Stars formed
• Stars are formed from giant clouds of dust and
gas.
• Then, from gravity, the cloud collapses into a
rotating gaseous ball.
• Once the new star gets hot enough it will
begin to create energy from a process called
nuclear fission.
• This created energy allows the star to glowfor
billions of years.
The Eagle Nebula
Death of Stars
• A star dies when it runs out of gases to burn.
• The Star will first expand into a red,
supergiant.
Death of Stars Cont…
• Then the star will collapse and explode.
– This takes billions of years.
• The size of the star determines how long it’s
life is.
– The bigger the star the shorter the life.
When Stars Explode…
• The Crab Nebula
This is what happens when a star explodes. The Crab Nebula is a result of a Supernova
that was seen in 1054 AD.(Image captured by Hubble Telescope).