Galileo and the Celestial Phenomena

Take your students on a journey from pre-telescopic astronomy to modern astronomy by learning about Galileo’s pioneering observations of celestial phenomena, including sunspots and the Northern Lights.

Student Learning Objectives:

Identify and correct possible misconceptions about ancient times
Understand the key stages of science’s development over time
Learn about the history of the telescope and the importance of Galileo’s observations
Discover/deepen some notions of astronomy and optics
Reflect on the relationship between ancient instruments and technological & scientific progress

Keywords

Astronomy, telescope, observations, time, sky, stars, planets, sunspots, helioscope, lenses, mirrors, light, geocentric theory, heliocentric theory, aurora borealis.

Age Range

11-13, 14-18

Setting

School, Museum (onsite or virtually)

Duration

5-6 hours (in school)
1.5 hours (in the museum)

Technical Requirements

Internet, smartphones, PCs, tablets

Connection with the curriculum

This virtual pathway is a multidisciplinary learning tool, the using of which can include elements from several subjects. It represents multidisciplinary elements for STEAM pedagogy. More specifically:

Middle school (11-13 year old students): This pathway is related to the subjects of History, Geography, and Science.
High school (14-18 year old students): Due to its interdisciplinary nature, this pathway is particularly suitable for high school students, encompassing the subjects of Philosophy, Literature, Science, Physics, Astronomical Geography, and Arts.

Structure

This educational pathway follows an inquiry-based pedagogical approach, organised into 3 logical stages:

Pre-Visit
Visit
Post-Visit

Teacher Support Materials

Useful resources, suitable for the age group of your students, are available at the “Teacher Support Materials” tab.

Follow-up Activities

Click on the “Follow-up Activities” tab to find out more activities for schools offered by the Galileo Museum. We also suggest two virtual pathways we think suitable for your students to continue their astronomical journey they began with “Galileo and the Celestial Phenomena”.

Pre-Visit

Phase 1: Provoke curiosity

You can start with a PowerPoint presentation (available at “Teacher Support Materials” tab) that uses the speaker’s notes, visible only to you, to offer hints on the procedure to follow and references to a wider documentation on the topics covered, including materials that will be given to the students at a later phase.

You can then use the following questions to initiate a discussion on how astronomical observations were made in the ancient times:

Why was it important to observe the sky in ancient times?
How did the ancients observe the sky and imagine the Universe?

Students should be then left free to respond and share their experiences and opinions. At this stage, your role is that of a facilitator, helping your students identify themselves with an observer of the past grappling with religious and social issues, astrological beliefs, orientation issues, and agricultural practices.

This discussion is followed by in-depth videos related to:

You can then proceed with a second group of questions that focus on students’ personal experiences with observing the sky:

Have you ever stopped to observe the sky at night? What did you notice?
A wide variety of objects can be seen with the naked eye: which ones can you easily distinguish? Do you know which planets are visible to the naked eye?
How do you tell a planet from a star?

The aim here is to encourage students reflect on the apparent motion of the vault of heaven, on objects easily distinguishable with the naked eye and the challenges of observing the sky without the modern means available today.

You can then use a PowerPoint presentation (available at “Teacher Support Materials”) to the representation of the celestial sphere, the geocentric system, and the Aristotelian conception of the universe. If you teach 14-18 year olds, you can also use the following videos:

You can then proceed with a third set of questions that address the problem of orientation to introduce one of the most versatile instruments of the past, the astrolabe, which will be described and explained more extensively during the visit:

How do we get to a place we’ve never been?
Can you orient yourself without GPS?

Finally, two generic questions about Galileo Galilei and a series of 11 short videos about his life can be used to provoke interest in the character and personality of Galileo, the protagonist of the museum visit.

At the end of the pre-visit phase, you can also share with your students useful materials to help them prepare their onsite or virtual visit to the museum and interact with the museum guide.

For further support, you can also contact Museo Galileo’s education team at: didattica@museogalileo.it

Note: All pre-visit materials are available at:

“Teacher Support Materials” tab
Galileo Museum website

Visit

Phase 2: Active Investigation

Activities, normally held in presence on the museum premises, can also be conducted online based on the circumstances.

During the visit, the museum educator asks students questions to test their knowledge regarding the methods of observation of the sky and the instruments used before the invention of the telescope.

Building on the activities you did during the pre-visit phase, the educator can ask your students the following questions:

Why has man observed the sky since ancient times and what practical problems could be solved by observing and calculating the position of the stars (orientation and calculation of the time of day and night)?
Would you be able to tell what time it is without a watch? What technique would you use?
What was the position of the planets in relation to the Earth according to the geocentric theory?
Do you know what instruments were used to measure time (day & night) in antiquity?

During this phase the museum educator explains and illustrates the use of the astrolabe, the sundial, and the night clock, comparing them to the tools we use today, such as the satellite navigation system.

Phase 3: Gather evidence from observation

Practical evidence accompanies all stages related to the discussion of astronomy in the pre-telescope era and the modern age.

For the pre-telescopic era

With the help of replicas, the educator shows the functioning of the instruments used in the past, such as the astrolabe and the nocturnal.
Using these instruments, people in the past were able to make important observations and to distinguish stars, planets and constellations: the educator checks whether the pupils have understood the difference between the various celestial objects.
Students try to find the time with the instrument replica by observing a pseudo starry sky.

For modern times

The focus here is on the history of the telescope and the analysis of how the telescope works by introducing Galileo’s discovery and use of the telescope as an astronomical instrument. Before proceeding, your students can be asked: How powerful was Galileo’s telescope and how did celestial bodies appear through it?

The museum educator can then proceed with the following tasks:

Analysis of the telescope’s structure and the lenses’ properties with a mention to the fundamental principles of optics such as reflection and refraction.
Evolution of the telescope: comparison between Galilean telescope and Keplerian and Newtonian telescopes.
Lenses and mirrors: differences and analogies (for high school students).

What method can be used to safely observe the sun?
Galileo’s main discoveries and insights into sunspots: how did Galileo observe the sun?
- The focus here is on the helioscope and its functioning.
Use of the camera obscura to recall how Galileo was able to study sunspots with the helioscope.

Comparison with modern images from space probes: differences and similarities with Galileo’s drawings and what he tells us about his discoveries.
Galileo had another intuition that would later be confirmed: the phenomenon of the Northern Lights.
Use of electrostatic machines to talk about the first experiments on the aurora borealis
Reconstruction of the telescope using educational kits, check at the same time whether the pupils have understood how the Galilean telescope is made.

The above tasks can be carried out by the students during both the on-site and virtual visit facilitated by the museum guide.

Phase 4: Discussion

The on-site or virtual tour to the museum ends with a visit to the original instruments on display in the museum’s rooms, as a stimulus for further reflection.

Post-Visit

Phase 5: Reflection

The aim here is to help your students reflect on the knowledge they acquired in the previous phases and develop their critical thinking.

Click on the “Teacher Support Materials” tab to find all you need to complete this phase. The materials organised according to the age group of your students include:

PowerPoint presentation including cards and videos of the topics covered during the visit, namely the measurement of time with astrolabes and nocturnals, the astronomical discoveries and the instruments of Galileo, the eighteenth-century machines to reproduce the effect of aurora.
Quizzes (and their answers)
Suggestions for group activities
Videos

Phase 6: Communicate explanation

In this phase, the aim is to encourage students to communicate their experience by learning to appreciating different points of view, the importance of teamwork and collaboration, and the added value of inclusion and diversity.

There are, of course, plenty of group-based activities you may already use in your everyday practice. From our side, we suggest the following activities, organised per age group.

Group activity for 11-13 year old students

Split your class into 4 groups. Each group is given an assignment as follows:

Group 1: pre-telescopic observations. Reconstruction of ancient instrument replicas based on downloadable instructions and reports on experimental observations.

Group 2: the Galilean revolution. Creation of a camera obscura and/or a helioscope to observe the sun with the help of downloadable instructions. Documentation of the results.

Group 3: the evolution of the sky’s observations. Draw a chronological timeline showing the new achievements in terms of greater knowledge of planets’ appearance (i.e. Saturn’s rings) and new discoveries (planets and satellites) in the Solar System in the 18th and 19th centuries.

Group 4: modern era discoveries. Make a scale model of the Solar System.