Asteroids - Teachers' Notes
     - Scavenger Hunt
     - The Universe
     - Asteroids
     - Types of Stars
     - Color
     - Galaxies
 For Kids
 To Student Projects
 Teacher's Guide
     - Goals
     - Background
     - Structure
     - Questions
 To Student Project


In this project, students will learn how to visually identify asteroids in SDSS images. Stars, galaxies and quasars are so far away that they do not appear to move, even if the are actually traveling very fast. Asteroids, on the other hand, are relatively close to Earth and appear to move quickly across the sky. Students can use this movement to visually detect asteroids in SDSS photos.

The SDSS Data Release 3 contains over 100,000 asteroids. Most fields contain at least one asteroid and many contain more than one. Some of the asteroids are bright and move very quickly, making them stand out. Others are dim and slow moving, and take a much more trained eye to spot. Everyone can find some asteroids in the data, but a skilled observer will find many more!

Project Goals

By the end of this project, students should be able to:

  • Know that stars are so far away that they do not appear to move, even over the course of a human lifespan
  • Know that in addition to the nine planets, the Solar System contains many small bodies called asteroids
  • Identify the location of most asteroids as between the orbits of Mars and Jupiter
  • Know that asteroids are made of material left over from the formation of the Solar System
  • Understand that asteroids and planets move relative to the more distant stars, and that this motion gives away their presence
  • Know that the SDSS camera takes pictures through five different filters over the course of several minutes
  • Explain how SDSS images can be used to detect asteroids - the asteroids move between the time the first and last picture is taken.
  • Identify fast and slow moving asteroids in SDSS images, and tell the difference between them

Background Knowledge

Students should be familiar with the solar system and the nine known planets. They should also be aware that the planets appear to move relative to the stars. This fact will make it easier for them to understand why asteroids also appear to move relative to the background.

A basic knowledge of color filters would be useful. If your school has a theatre, obtain a few gels from the lights for a demonstration of filters. Students should also know or be taught about how red and green light combine to make yellow.

No mathematical manipulation is required in this project, except for students keeping track of how many asteroids they find!

Project Structure

This project is relatively short and could be completed in 1 - 2 hours. The time it takes depends mainly on how long you wish to give students to search for asteroids. You probably will need about 20 - 25 minutes of introduction to discuss asteroids and camera filters.

Students will then find three asteroids for practice. You may want to check to be sure they have really found the asteroids (the positions of the asteroids are marked on diagrams in the answers). This process should take 10 - 15 minutes.

The asteroid hunt can be as long or as short as you like. Fifteen to thirty minutes is probably about right. After the hunt, take the groups that have found the most asteroids and have the class verify their findings. This is a good opportunity to emphasize that scientific findings must be verified by others!

Questions and Exercises

Questions are designed to get students thinking about the way scientists work. Exercises are designed to get students to explore using SkyServer data to solve problems. For answers to all questions and exercises, click here. To see the answers, you must have the Adobe Acrobat PDF viewer installed on your computer. Acrobat is available for free download at Adobe's web site.

For specific information on any part of the project, click Next