Astronomy Review

7th Grade Science

Love the Earth!• It takes the Earth 24 hours to rotate

on its axis.

• The Earth’s rotation on its axis causes night and day.

• For the Earth to make one full revolution around the sun, it takes about one year, or 365 days.

The Reason for the Seasons• The reason for the seasons on Earth

is due to the tilt of the axis as it moves around the sun.

• During a full moon a lunar eclipse can occur.

• The differences in how much the moon pulls on different parts of the Earth causes the tides.

Under the moonlight…

• It is easier to see a lunar eclipse than a solar eclipse due to the fact that you must be in the moon’s shadow to see a solar eclipse.

• The moon includes: – Marias – Highlands– Craters

So, you want space travel???

• Accommodations for space travel include: – Spacesuits that handle a wide variety of

temperatures– Methods to move around– Dealing with zero gravity

• Because astronauts do not have protection of the Earth’s atmosphere, they must wear spacesuits to protect them from solar radiation.

On Earth we need…• For life on Earth, it is necessary to

have: – Liquid water– Suitable temperatures– Atmosphere containing gases living

things need• An equinox occurs when neither of the

poles are pointed towards the sun.

Layers of the Atmosphere

• The Troposphere– Is 7 miles up– The closest layer to Earth– Contains 75% of our atmospheric gases– Has weather, clouds, and smog

Layers of the Atmosphere

• The Thermosphere– 50 miles and upward– Warmest layer of the atmosphere– Contains the ionosphere and exosphere– Reflects radio waves

Layers of the Atmosphere

• The Stratosphere– Jet stream is located here– Little to no water vapor– 7-30 miles upward– The ozone layer is located here

Vocab, vocab,

vocab!!!Maria Vast, dark plains on the moon made of basalt

Axis Imaginary line passing through the center of a planet that the planet spins around

Orbit Path an object follow in spaces as it revolves around another object

Solar Eclipse

Occurs when the moon passes between Earth and the sun, blocking the sun’s light from Earth

Tide The daily rise and fall of the oceans caused mainly by the gravitational pull of the moon

Vocab, vocab, vocab!!!

Spring tide Tides that are the most extreme, occur twice a month at full and new moon phases

Neap tide Tides that are the least extreme, happen twice a month, at first and last quarter moon phases

Solstice One of two days in the year when hours of daylight and hours of darkness are at their greatest and least

Rotation Spinning of a planet, moon, or sun or other object around its axis

Crater A bowl-shaped hollow in the ground, caused by a volcano or by a meteor strike

Which season?

A = SummerB = Fall C = WinterD = Spring; Not visible due to the position of the sun

Did someone say moon phases?

• Letter A = full moon• Letter C = new moon• A lunar eclipse would = C• A solar eclipse would = A• Neap tide = AC• Spring tide = BD

The tides that bind

• Pictured above is a SPRING tide

Is there a man on the moon?

• The moon takes 29.5 days, or one month to rotate around the Earth.

• We can see the moon each day because the Earth rotates on its axis so that it the same moon phase can be seen by all.

• Because it takes the moon the same amount of time to rotate and revolve, we see the SAME side of the moon.