Abstract:

At the Department of Mathematics and Physics of Roma Tre University there is an astronomical garden that we call AstroGarden. Here, among grass and trees, shining in its brass support, a globe stands out. It is a special globe, able to simulate the state of illumination of the Earth in this exact moment. We call it an oriented globe, since it simulates the orientation that the Earth has with respect to the Sun. Thanks to this globe, it is possible to discover time zones and seasons. Using a gnomon, in fact, it is possible to observe how its shadow changes in different points of the globe.

Over the years we hosted in our garden schools and children of all ages, from primary to high school, so that they could (re-)discover the motions of the Earth in a new and evident way. During their visit, typically lasting an hour and a half, they could enjoy the garden experiencing the use of the oriented globe and also observing the Sun through a telescope.

In recent months, driven by the Covid-19 crisis, we transformed our visit to the AstroGarden in a distance education activity: with a 20 minute video, we present the oriented globe and show the way in which it can be used. We also provide a guided description of how to orient any globe, so that the audience can fully replicate the experience at home and at school. We explore the different positions the Sun has in the sky during the day, the significance of time zones and of the seasons in the two terrestrial hemispheres. Furthermore, we analyze the meaning of the astronomical noon, and the reason why long periods of light and dark alternate at the poles.

Now the video is freely available on YouTube [1] and it can be used also by teachers directly with their students in order to make them work with oriented globes or as a guide to build their own activity. It can be watched entirely but also divided into pieces, alternating with further explanations or other activities, as we used it during the European Researcher’s Night in November 2020. On this occasion, we organized a live broadcast: we showed the video by dividing it into parts, and challenged the audience with a quiz that wanted to engage them while testing their understanding of the phenomena treated. The recording of the broadcast has been watched so far by more than 1000 people [2]. Furthermore, we recently proposed the video during a training course dedicated to aspiring primary school teachers, receiving their feedback. In this talk, we present our work, the feedback we received and its future prospects.

References:
[1] The virtual tour can be found at: https://www.youtube.com/watch?v=osM8paBQEGE. The video is in Italian language, with English subtitles.
[2] The recording of the live broadcast can be found at: https://www.youtube.com/watch?v=ULw6iGkZf3o&list=PLCQ44gAvV-zsOblr8nmh0u_SxUv9KhIhY

Keywords:

Globe, oriented globe, seasons, time zones, astronomy, astronomical noon, virtual tour.