∙ Scientists use models to help understand and explain how things work. ∙ Space scientists use models to study things that are very big or far away. ∙Models help us make and test predictions. ∙ All models are inaccurate in some way. ∙ A model can be an explanation in your mind. ∙ Two-dimensional (2-D) models show the dimensions of height and width. (ex: a picture) ∙ Three-dimensional (3-D) models show the dimensions of height, width, and depth.

Note: Don’t move on to new slide till after we measure albatross

2km

3,000km, 30,000km

Hand out worksheet

4cm=_______mm 2m=________cm 50m=_______cm

Now we know….. Over 1 hundred Earths fit across the Sun.

The Is only about one- fourth the size of the In diameter, so the is much bigger than the Moon.

Write new number order on the back of the cards in a different color? Don’t erase old order numbers.

Actual sizes of the ten objects- House = 25 Meters long Person A = 1 Meter tall Person B = 1 Meter 70 cm tall Moon = 3500 km diameters Ball = 60 cm Star A : Betelgeuse = 900,000,000 km diameter Star B: Sirius B = 12,000 km diameter Star C: Rigel = 84,000,000 km diameter Venus = 12,1000 km diameter Car = 25 cm long

How big something looks and how big it really is can be very different. An object looks bigger when it’s closer. An object looks smaller when it’s father away The Sun looks bigger than other start because it’s a whole lot closer. The Sun looks the same size as the Moon because it’s much farther away than the Moon.

Light years away video

With your group, cut out these cards. Divide the cards evenly.

Use the category cards to sort the sky objects..

Now Scientist, I’ve come across some new evidence. As I read the new evidence, take notes so you will be able to resort your cards. (see pages )

Pass out Visual Chart of the Sizes of the Planets.

Concept: There are many things in the Universe that are much larger than the Sun.

How far away are the clouds? -top of the tallest mountain? -the beginning of space?