To understand how our knowledge of the sky has been enhanced by telescopes.
By grade six, students have a good base of general knowledge to work with regarding stars, the moon, and the sun. They should know, for instance, that the patterns of stars in the sky stay the same, that the moon has phases, and that the sun is a star. They will likely have done naked-eye observations before and should have the skills to do so again. Students will also know about telescopes and that they help humans better observe stars and moons.
This lesson will build on students’ prior knowledge of these things, with an emphasis on accurate descriptions of the moon, stars, and planets as seen from earth and on the motion of planets relative to the stars. (Benchmarks for Science Literacy, p. 240.)
These observations will be discussed in the context of Galileo’s use of the telescope and his discovery of Jupiter’s moons. At this level, it is important to introduce characters and stories in the history of science so that students have a base for more complicated science stories and concepts that will be learned in later grades. (Benchmarks for Science Literacy, p. 238.)
In this lesson, students will make their own night-sky observations, diagram and describe what they see, and will then look at pictures taken by telescopes. They will compare the two ways of observing to confirm what telescopes can reveal about the night sky. They will also learn about Galileo and contemplate how the telescope helped him make his discoveries 400 years ago.
Students will do an at-home night-sky observation assignment. Part of the observation involves using binoculars, so if you can gather up extra pairs of binoculars for your students, it may be helpful.
Since this lesson will incorporate Galileo and his discoveries, students should begin by using their Sky Watching student esheet to visit the From Galileo to the Hubble activity. This activity is a brief timeline beginning with Galileo and taking the reader up through the Hubble telescope. It gives a good overview of how observing the night sky keeps improving. When students have finished, discuss these questions with the class.
- Do you think that when Galileo made observations it was the same as it is today?
(This question will gauge whether or not students understand that early scientists had more crude equipment. They should understand that when Galileo was observing, he had a simple telescope, and today some scientists use the Hubble to see more.)
- Do you think Galileo did naked-eye observations? How do you think that compared to using a telescope?
(Student answers will vary.)
Tell students that in this lesson they will have the opportunity to do some sky observing just as Galileo did and just as many scientists do today.
Students will consider the history of night-sky observing by doing their own observations, first naked-eye, then with binoculars, and then looking at the results of telescope observations.
Have students look at the Night-Sky Observations student sheet. Review the instructions with the class and clarify anything students may not understand.
Even though the student sheet directs them to use binoculars in the final part of the assignment, if binoculars are not available, instruct your students to make only naked-eye observations.
After students have completed their night-sky observations on their own, conduct a class discussion in which students can compare their diagrams and discuss their observations.
Then, have students use their esheet once again to explore Stars. They should spend five to ten minutes exploring pictures taken by the Hubble telescope.
Afterwards, use these questions to allow students to compare the Hubble photographs to what they observed with their own eyes. Ask students:
- What did you learn from your night-sky observations?
(This is a fairly open-ended question. Students should have noted that the stars moved in the sky, that some stars are brighter than others, etc.)
- If you had the opportunity to use binoculars, what did the binoculars allow you to see?
(Binoculars, for this assignment, are an intermediary technology piece to demonstrate that students can see more details.)
- Compare what you saw in your own observations to what can be seen through the Hubble telescope.
Students should reflect on the differences between their own observations as compared to those made by the Hubble. Assign them to write a paper titled “Naked-Eye Sky Observation Compared to One Using a Telescope.” Students should discuss the process that they went through and reflect on what they were able to observe with the naked eye, the changes that they saw, and how our knowledge of the planets and stars can be enhanced by the telescope.
Students can also continue to explore the Galileo Project and write about how the telescope impacted the life of Galileo. Would he have made his discoveries without the telescope?
This lesson may be supplemented by the related Science NetLinks lesson, Looking into Space, in which students explore the make-up and history of the telescope.
NASA's PlanetQuest site exists to keep you updated on the latest events and information in the unfolding story scientists' search for other planets like Earth in the universe.
To see images taken via telescopes and amateur photographers, go to David Hanon's Astronomical CCD Imaging Page. Students can see images taken through an amateur telescope and a picture and description of the equipment used.