|Until the 20th Century, astronomers learned virtually all they knew about sources in the sky from only the tiny fraction of electromagnetic radiation which is visible to the eye. However, as astronomers have discovered how to collect radiation outside this part of the spectrum, they have been able to learn much more about the Universe. Many objects reveal different aspects of their behavior at different wavelengths. Other objects are completely invisible at one wavelength yet show up clearly at another. We will begin our study of multiwavelength astronomy by first investigating image processing software and then the nature of light.|
|ACTIVITIES on Image Processing
Throughout this course,we will be using images from professional telescopes and image processing software to investigate astronomical objects, phenomena and concepts. The following activities are to familiarize yourself with the tools you will be using.
| Introduction to Image Processing|
In the Hands-on Universe Book 1, do pages 3-13. You may do "A Color Coding Activity" (p. 14-15) if you have time.
| Browser's Guide to the Universe|
In the Hands-on Universe Book 2: Finding Features, do pages 6-8. This will introduce you to images of some of the astronomical objects we will be studying in this course.
| Moon Match Unit|
In the Hands-on Universe Book 2: Finding Features, do pages 9-14. Practice using image processing software by manipulating images of the moon to match the ones given.
|ACTIVITIES on Powers of 10 and Scientific Notation
When studying the origin and evolution of the universe, scientists must consider the smallest of particles such as the quark to the largest of structures like superclusters of galaxies. Scientists, therefore, need ways of dealing with very large and very small numbers.
| Powers of 10
This lab uses a Java applet, Powers of Ten, to let you view the Milky way from 10 million light years beyond Earth and then zoom in an order of magnitude each time until a single proton fills the screen. You will want a printout of this worksheet. The movie, Powers of Ten , which can be obtained from the ROTC program upstairs, is also an excellent reference.
| Scientific Notation|
Learn an easier way to write very large or very small numbers. You will need a printout of this worksheet to record your answers on.
| Is there a googol of anything?|
If someone asks you, "what's the biggest number you can think of," what comes to mind? Back in the 1940s, American mathematician Edward Kasner was asking himself the same question. He decided to ask his nine year-old nephew what he would name a really big number. His nephew's answer was, "a googol!" - 3 worksheets here.
| Using Large and Small Numbers|
Supplementary Activity 5 from the Hands-On Universe Book 4 (Measuring Size) p. 22
| Making a Cosmic Calendar|
Understanding when important events in the evolution of our universe happened relative to each other can be very difficult for us to comprehend. In this activity, you will be making a cosmic calendar with all the events compressed into the scale of one year.
|ACTIVITIES on the Wave/Particle Duality of Light
A huge part of what we know about the universe is from the study of light or electromagnetic radiation. Light has both a particle and a wave nature. Let us first begin by discussing the definition of a wave in general. A wave can be thought of as a disturbance that travels through a medium (as in the case of a sound or water wave) or through a field (such as a light/electromagnetic or gravitational wave). The first few activities deal with types of waves and wave parameters. The remaining activities explore famous experiments by Newton, Young, Hertz and Einstein leading to the wave/particle theory of light.
| Types of Waves
Explore different types of waves and wave parameters in this virtual lab. You will want a printed copy of the worksheet. The applets are here.
Lesson 2: Wave Properties
Do all "Check Your Understanding" questions from Anatomy of a Wave to The Wave Equation.
| Wave Phenomena and the Electromagnetic Spectrum
Examine the properties of shadows, create a model to explain diffraction and measure the wavelength of laser light.
| Wave Theory of Light
Recreate some of the experiments that led scientists like Huygens and Young to believe that light had wave-like properties. Online simulations and information will also help you with this lab.
| Newton’s Prism Experiments
Recreate Newton's experiments that made him believe white light was a composite of different colors.
| Investigating the Photoelectric Effect |
A virtual lab experiment to investigate how the photoelectric effect gives evidence for light as a wave or light as a particle. You can also play with the photoelectric effect in this applet.