What two factors keep planets orbiting around a star like the sun? Inertia Gravity

What two factors keep planets orbiting around a

star like the sun?

•Inertia

•Gravity

Planet- one of the 8 celestial bodies revolving around thesun. Planet requirements-

1. Revolve around sun 2.be spherical 3.clear orbital path.

We ___________ around the sun.revolve

When we orbit or revolve around the sun, we do not travel in a perfect circle. We revolve around the sun in an elliptical path.

An ellipse is kind of like a squashed circle.

Pluto is a considered a dwarf planet. It lost its ‘planet’ status because it had NOT cleared its orbital neighborhood.

•Mercury•Venus•Earth•Mars•Jupiter•Saturn•Uranus•Neptune

What are the planets ofour solar system?

How can we remember the order of these 8 planets?

By remembering this sentence:

My very eager mother just served us nachos!

Revolving

Since there are two planets in The Solar System that start with M, Mercury and Mars, how can we remember which is

first?M = VEM =JSUN

My = Mercury

Mother = Mars

Name the inner planets?

Name the outer planets?

How are they different?

Mercury, Venus, Earth, Mars

Jupiter, Saturn, Uranus, Neptune

Inner planets are terrestrial or rocky.Outer planets are gaseous.

What do we say to remember our planets?

My Very Eager Mother Just

Served Us Nachos!

Mercury Venus Earth Mars Jupiter

Saturn Uranus Neptune

An asteroid belt separates the inner and outer planets.

Pretend you are traveling out from the Sun to Neptune.

Feel the distances!

http://www.classzone.com/books/earth_science/terc/content/visualizations/es2701/es2701page01.cfm