## Shop Windows to the Universe

The Universe at Your Fingertips 2.0 DVD from the Astronomical Society of the Pacific is in our online store, filled with Earth and space science resources.

# A Solar System Model Builders Guide

Imagine you want to build a scale model of the solar system.

First, you need to decide on a scale for your model. Let's say we decide we'll use a marble that is 1 cm across to represent the Earth. Then how big would the Sun and the other planets be and where would they go?

To figure out the sizes of the planets and the Sun compared to our Earth marble, you need to multiply the 1 cm size of Earth by the relative sizes of the Sun and the planets. A marble for the Sun would have to be 109 cm across (bigger than a big beach ball), and a marble for Mercury would be about the size of your pencil's eraser.

Next, you need to figure out where to put your model planets. How far are they from the Sun? At this scale, Mercury would be 46 m (151 feet) from the Sun, Earth would be 118 m (387 feet) from the Sun, and Pluto would be more than 5.8 km (3.6 miles) from the Sun!

#### Shop Windows to the Universe Science Store!

The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

## Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

## The Beginning of the Solar System

Scientists believe that the solar system was formed when a cloud of gas and dust in space was disturbed, maybe by the expl osion of a nearby star (called a supernova). This explosion made waves in space...more

## The Solar System

The solar system is made up of the Sun, the // Call the planets count function defined in the document head print_planet_count('planets'); planets and // Call the planets count function defined in the...more

## Eris - a dwarf planet

Eris is a dwarf planet in our Solar System. Eris is a lot like Pluto, which is also a dwarf planet. Eris and Pluto are both very far from the Sun. They are both very, very cold. Eris was discovered in...more

## What is a planet?

Do you know what a planet is? Guess what... astronomers are not quite sure what a planet is! Mercury, Venus, Earth, and Mars are the planets closest to the Sun. They are definitely all planets. They are...more

## Orionid Meteor Shower

Meteor showers are times when you can see a lot of meteors in one night. There are several different meteor showers. Each meteor shower happens at the same time every year. There is a meteor shower in...more

## Leonid Meteor Shower

The Leonid meteor shower is one of several major meteor showers that occur on roughly the same date each year. The Leonids typically "peak" (are at their greatest level of activity) in mid to late November....more

## Meteor Showers

A meteor shower is an astronomical event during which many meteors can be seen in a short period of time. Most meteor showers have a peak activity period that lasts between several hours and a couple of...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information.