Astronomy is one of the few sciences where the data (star-light) can be seen by all. Yet, there is a disconnect between a typical undergraduate lecture and, for example, where a planet may be in the sky and how to observe it. With the advent of moderate cost, high-quality 'back-garden' astronomy, and standard computers powerful enough to produce…

A practical experiment is described to estimate the distance to a star using simple equipment, suitable for secondary or undergraduate students. The brightness of the star is visually matched to a miniature filament lamp, and its distance inferred from the inverse square law. Students gain an appreciation of astronomical units and practice in…

The microNet ([mu]Net) project aims at the development of an extended network of educational cosmic ray telescopes in the geographical area of western Greece. In the initial phase (2022-2023) of the project, 20 telescopes will be deployed in high school buildings, while more than 50 schools will attend the educational program of [mu]Net by…

Data from the Kepler satellite were analysed using the Mikulski Archive for Space Telescopes database. With the participation of 53 students, we determined the parameters of the HAT-P-7b (Kepler-2) exoplanet system (transit duration, planet-to-star radius ratio, orbital period, semi-major axis and star mass). We used approaches that are easy to…

In this paper, we present a physical modeling activity whose objective is to allow students to determine the differences between a disk and a sphere using pure scientific criteria. Thereunto, we reproduce the Sun-Earth-Moon system with low-cost materials and compare the illumination effects on the Moon considering two possible shapes for it (a…

This paper has a didactic aim. Indeed, starting from the well-known principle of free fall discovered by Galileo Galilei, we want to make some reflections that we consider useful for secondary school students. Being the acceleration invariant with respect to Galilei's transformations, it is useful to underline that the free fall in a gravitational…

Teaching cosmology at the undergraduate or high school level requires simplifications and analogies, and inevitably brings the teacher into contact with at least one of the pedagogical interpretations of the expanding Universe. The by far most popular interpretation holds that galaxies in an expanding Universe are stationary, while space itself…

The Physics Laboratory of the Hellenic Open University has constructed a small scale and low cost air shower detector suitable for operation inside the classroom or school laboratory ([mu]Cosmics detector). In this work we present some of the educational activities foreseen with the [mu]Cosmics air shower detector, as well as the assessment of a…

In 1919, Eddington and Dyson led two famous expeditions to measure the bending of light during a total solar eclipse. The results of this effort led to the first experimental confirmation of Einstein's General Relativity and contributed to create its unique and enduring fame. Since then, similar experiments have been carried out all around the…

An internet poster recently floated the idea that friction with a recently denser interstellar medium causes global warming. Despite its superficially ridiculous nature, refuting this proposition is an interesting quantitative exercise.

Throughout the long history of astronomy, scientists have repeatedly written fictional stories, which often lend themselves to use in the classroom thanks to the authors' in-depth knowledge and an appealing storyline. This article uses the novel 'The Black Cloud', written by the well-known astronomer Fred Hoyle, to show which physical-astronomical…

In this study, the tilt of the Earth's axis was measured during a lunar eclipse using a telescope based on the angle between the lunar orbit and ecliptic planes being considered as approximately zero. The presented method not only offers a practical and reliable way of measuring the axial tilt of the Earth during a lunar eclipse but also helps in…

This paper presents exemplification of the ways in which teachers can garner the interest piqued by the recent detection of gravitational waves. The intention was to develop a teaching module based around this exciting new branch of astronomy and to use this as an opportunity to bring cutting-edge science into the classroom, whilst allowing…

In recent years, general relativity (GR) and gravitational-wave astronomy have emerged both as active fields of research and as popular topics in physics classrooms. Teachers can choose from an increasing number of modern instructional models to introduce students to relativistic ideas. However, the true potential of an instructional model can…

Given the great interest that black holes arouse among non-specialists, it is important to analyse misconceptions related to them. According to the author, the most common misconceptions are that: (1) black holes are formed from stellar collapse; (2) they are very massive; (3) they are very dense; (4) their gravity absorbs everything; and (5) they…