Looking at the Sky in a Different Light

By learning how different types of telescopes detect different parts of the electromagnetic spectrum, students are able to compare the capabilities of each telescope. They can then infer what this means for the future of astronomical research.

In this activity students will

• Learn about the electromagnetic spectrum.
• Compare the properties of gamma rays, X-rays, ultraviolet light, visible, infrared, microwaves and radio waves
• Understand that astronomers build a complete picture of an object in space by making observations across the electromagnetic spectrum. Each type of radiation reveals something different about the object.
• Research and compare the qualities of telescopes that detect different parts of the electromagnetic spectrum.
• Communicate their findings by creating a poster.

Suggested questions to engage students

• How does the Earth’s atmosphere interfere with astronomers’ view of space?
• Technologically advanced telescopes generate huge amounts of data. What kind of problems does this create? What solutions can you think of?
• Why is it important that light from the universe is invisible to our eyes?
• Why do we need different telescopes to see different types of light?

What to do

Students can view the video for an introductiory comparison between two telescopes. 

Begin this exercise by examining the six different images of the Centaurus A galaxy shown in the video below. 

How the sky appears in different types of electromagnetic radiation allows us to see what is otherwise completely invisible to our eyes.

Instructions for students

What information can astronomers gain by viewing Centaurus A in gamma rays, X-rays, ultraviolet light, visible light, infrared and radio waves? You will need to research the different forms of electromagnetic radiation to answer this question.

Research different telescopes (including Australian ones) that can view the sky in the different forms of light and fill in a table with the following headings: 

• Name of telescope
• Where is it based?
• Which electromagnetic radiation it detects
• How far can it "see"?
• Special discoveries?
• Image of telescope

Analyse your table of information once it is complete. What are some of the things that stand out for you? Use the information in the table to design a poster that effectively displays your research.

Think about what you would like to highlight in your poster before you begin. The following animation highlights the observable distance that particular telescopes can reach. It provides an example of what you might like to highlight in your poster.

Extension exercise

The new generation of telescopes are technologically more advanced. Scientists are aiming to uncover how the first stars and galaxies formed as well as the mysteries of dark energy and dark matter. The problem with these telescopes, is that the amount of data detected will be immense. For example, when the Square Kilometre Array (SKA) is complete, it will generate more data each day than the total amount of data on the internet today!

In groups, discuss the following questions:

• What are some of the advantages and disadvantages of uncovering these mysteries?
• What are some possible solutions to the problem of having so much data to analyse?

Suggested links

• Zooniverse is a collection of citizen science projects where everybody can help analyse data for astronomy, biology, medicine, history, social science and arts projects.
• iTelescope is a website where you can hire time to control a real telescope virtually and obtain your own real data to analyse.