Online activities

Do you need time to relax with friends, do you want to create a good working environment in your team or would you like to add an activity at your school? OLA offers a collection of games and talks that can be done online for schools and companies.

Games and Riddles



We have a collection of 6 themed crosswords, related to various areas of Astronomy. These games were designed to be solved with consultation and research, and can be solved individually or in groups. They were made to help you understand a little more about the solar system, famous astronomers, or galaxies and astrophysics.


Letter Soup

One of our available content is a series of 6 letter soups with various astronomy concepts, from the most basic words to specific expressions. These letter soups are accompanied by an explanatory text summarising the various concepts used, which can then be further developed according to the curiosity of the participants.

Astronomy Quiz

We have prepared a quiz with some astronomy questions, which can be solved in person or online. The quizz is also designed to elucidate and clarify some common misconceptions about astronomical concepts. Watch out for mousetraps and pay attention to the questions and answers!



How do we weight the Universe weigh?

In this presentation we will discover what are the tricks and processes by which researchers measure the masses of celestial bodies, how do we know that only 5% of the matter in the Universe is composed of normal matter, that is, neutrons and protons, and understand that the Universe has today an ever faster expansion.


Surfing a gravitational wave

In this lecture we will learn that gravitational waves are disturbances in space and time that propagate at the speed of light. We will understand how they are detected and discover that they can offer us a lot of information about distant stars and black holes dozens or even millions of times more massive than the Sun.


Discovering black holes

In this presentation we review the theoretical discoveries and the scientific process that led to the realization that black holes are a consequence of General Relativity, that they are real astrophysical objects that can be localized and that in fact there is a supermassive black hole in the center of our galaxy.


The sky tonight

In this presentation we will take a trip through the night sky starting with the orientation by the polar star and the identification of the constellations. We will learn where the stars come from, how they evolve and how they can die. We will discover the difference between star clusters and galaxies, and we will know that we are made of a type of matter that is not more than 5% of everything that exists in the Universe.


Seasons, Precessions, Constellations, and other confusions

This lecture aims to explain how the Earth-Sun system works, the effects of different seasons of the year in various places on our planet, and how the sky we observe varies slowly and predictably over the centuries.


Landings on Mars – problems and solutions

In this presentation we will explore the missions to Mars in the last few decades, with a special focus on the recent Curiosity and Perserverance, as well as to understand the challenges that a future human mission to the red planet entails. Let’s see how it is possible to land on Mars and explore the methods that have already been tested and those that are just imagination.



This lecture shows the ingenious techniques that are used daily by astronomers in the search for exoplanets, planets that orbit stars other than our Sun. We will also realize that there is a wide variety of exoplanets, and that the investigation of these fantastic objects still has a lot to go on.


Zoo of Stars

In this fascinating lecture, we will observe the stars as if they were exotic animals, realizing their enormous variety of sizes, colors, and classes. Let us learn about their life cycles and understand that our galaxy is an authentic zoo of different and strange stars.