Purpose
To identify different forms of energy produced by the sun.
Context
This lesson was developed by the Challenger Center as part of NASA's MESSENGER Mission, of which Science NetLinks is a partner.
In this lesson, students will perform simple experiments that will help them to explore unseen energy produced by the sun. During the course of this lesson, students will be exposed to these concepts: the sun produces both visible and invisible forms of energy; the light we see is visible energy produced from the sun reflected off surfaces; ultraviolet energy emitted from the sun can produce skin burns and cancer; and there are ways of blocking ultraviolet radiation. Refer to the Science Overview of the lesson for a summary of the science content relevant to the activities in the lesson. Refer to the Lesson Overview for a more detailed explanation of what students will learn from the lesson.
Planning Ahead
Note: Parts of this lesson were extracted from the unit, Staying Cool.
Ultra-violet Detection Beads are required for this lesson. They can be purchased from Educational Innovations.
Motivation
Have students take part in the discussion presented in the Warm-Up & Pre-Assessment section of the Sensing Energy lesson plan. Finding out what students know about light will serve as a basis for exploring two other aspects of energy from the sun—heat and ultraviolet (UV).
For the MESSENGER mission to Mercury, it is important to study these different forms of energy—particularly for the preservation of the spacecraft, which will be exposed to their very dangerous effects when it flies outside the Earth's protective atmosphere.
Development
Have students perform the activities in the two-part Procedures section. For Part 1, students will use Ultra-violet Detection Beads to look for and analyze changes in the color of the beads when exposed to different sources of light. For Part 2, small groups of students will put UV beads in a number of open film cannisters (under different conditions) and place them in the sun. Each group should fill out the Student Worksheet #1 to record and later discuss their findings with the rest of the class as part of the Discussion and Reflection phase of the lesson.
Assessment
For the Assessment section of the lesson, have students design their own test to show how the UV beads respond under different conditions.
Finally, encourage students to make connections between what they have learned about the sun's energy and the MESSENGER mission. Moreover, have them think about and discuss different ways that the MESSENGER spacecraft can be protected from the harmful effects of the sun's radiation. A MESSENGER model can be constructed beforehand to aide in this discussion.
Extensions
Color Burst helps students gain experience in asking questions and conducting inquiry by exploring the separation of colors in water and other solvents. It also encourages students to communicate and share findings of their investigations.
The focus of the Does Soap Float? lesson is scientific inquiry. In the lesson, students form hypotheses and carry out an investigation in order to answer a central question.
The experiments in Sink It are designed to encourage student skills in experimental design, testing simple hypotheses, and grouping objects by common characteristics.
For students who know about other planets, ask them to speculate about how much of the sun's power reaches them. Ask about visible light, heat, and UV radiation. You may want to mention here the other forms of solar energy discussed in the Science Overview, which includes gamma, X rays, infrared, and radio waves. Study questions (or research topics) may include:
- How would the sun's energy be different on different planets such as Mercury or Pluto?
- What features about the other planets make them different from our planet?
- Why are those features important when we think about light, heat, and UV radiation?
To make this lesson more relevant to students' knowledge of biology in the early grades, explain how insects use their ability to sense ultra-violet radiation. Butterflies and bees see ultraviolet light as a distinct color that makes certain markings on flowers very vivid to them and guides them to the nectar tubes.
