3. identify and describe the components of our Solar System: Sun, planets, dwarf planets, moons, meteors, meteorites, asteroids, and comets.
Using the following resources, construct and complete a table/other graphic organiser which gives information for: Name, Description for Sun, planets, dwarf planets, moons, meteors, meteorites, asteroids, and comets.
For the individual planets, complete another table /organiser that includes: Name, Distance from sun, Light time from sun, Moons, Length of Day, How it formed., Named after
History of Solar System PPT (below left)
NASA Solar System Overview (below right)
Text pp323-7; 336-7
Reading: Planets (second row below left)
Reading Names for Planets (second row below right)
5. describe and compare features of the Sun and Moon (e.g. light source, size, distance from earth, composition, gravity)
View PPT Earth, Sun, Moon PPT and complete the Worksheet
6. construct or participate in a model to demonstrate the relative positions, sizes and distances involved in the Solar System.
view videos
Planets Scale Model: [2.18] or extended version [7.21]
Scale of the Large [11.02]
Scale of Earth and Sun [9.30]
Scale of Solar System [12.30]
8. Explain day and night in terms of the Earth’s rotation on its axis.
View videos:
- What Causes Day and Night? [3.02]
- Day & Night Explained [1.02]
- Earth Rotation (Earth from space) [1.17]
Carry out Investigation 8.3 from Text p359
Evaluate the usefulness of the model.
9. Explain Earth’s year and seasons in terms of its revolution around the Sun.
Earth's revolution around the sun takes 365.256 years. If we just counted the 365 days, our calendars would gradually get out of line with the seasons. We would have summer in June for many years!! So leap years were invented to keep the days on track.
Mostly every four years, an extra day is added to the calendar - February 29. That takes care of the .25 years (4 x 0.25 = 1 year) but there is still that .006! So there is a way to fix that too.
Look at the example below. Use the formula to identify if your birth year was a leap year (Text p355)
Many people believe that Earth is closer to the sun in the summer and that is why it is hotter. And, likewise, they think Earth is farthest from the sun in the winter.
Although this idea makes sense, it is incorrect.
It is true that Earth's orbit is not a perfect circle. It is a bit lop-sided. During part of the year, Earth is closer to the sun than at other times. However, in the Northern Hemisphere, we are having winter when Earth is closest to the sun and summer when it is farthest away! Compared with how far away the sun is, this change in Earth's distance throughout the year does not make much difference to our weather.
There is a different reason for Earth's seasons.
Earth's axis is an imaginary pole going right through the center of Earth from "top" to "bottom." Earth spins around this pole, making one complete turn each day. That is why we have day and night, and why every part of Earth's surface gets some of each.
Earth has seasons because its axis doesn't stand up straight.
What caused Earth to tilt?
Long, long ago, when Earth was young, it is thought that something big hit Earth and knocked it off-kilter. So instead of rotating with its axis straight up and down, it leans over a bit.
The big thing that hit Earth (called Theia and thought to be an ancient planet) also blasted a big hole in the surface. That big hit sent a huge amount of dust and rubble into orbit. Most scientists think that that rubble, in time, became our Moon.
As Earth orbits the sun, its tilted axis always points in the same direction. So, throughout the year, different parts of Earth get the sun’s direct rays.
Summary
Earth's tilted axis causes the seasons. Throughout the year, different parts of Earth are pointed towards the sun, while the opposite hemisphere is pointed away from the sun. So, when the North Pole tilts toward the Sun, it gets more sunlight - it's summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, it gets more sunlight - it's winter in the Northern Hemisphere.
View videos:
Complete Scootle Seasons interactive (Australian focus)
View and interact with Seasons animation (Footprints) below