Contextualization

The Astronomical Unit (AU) is a measure used by astronomers to calculate distances in the solar system and beyond. An AU is the average distance from Earth to the Sun, about 150 million kilometers. This unit is extremely useful for scientists as it allows them to discuss huge distances in more manageable terms.

The concept of AU was introduced in the 17th century by the astronomer Johannes Kepler as a way to simplify the equations used to describe the orbits of planets. Since then, it has become an essential tool for astrophysics, enabling a better understanding of our solar system and solar systems of other planets.

In particular, AU is an essential tool in the search for exoplanets - planets that orbit stars beyond our sun. By measuring the distance between these planets and their stars in AU, astronomers can determine crucial information such as the probable temperature of the planet and whether it is in the 'habitable zone,' where life as we know it could exist.

The Importance of the Astronomical Unit

As science students, understanding the Astronomical Unit and its application is fundamental to comprehend the universe around us. Distances in the universe are so vast that they become difficult to imagine. The AU is a way to bring these distances into a more understandable context, facilitating the understanding of the scale of our solar system and beyond.

Moreover, the Astronomical Unit is a key to space exploration. By understanding the distances between celestial bodies, we can plan space missions, calculate travel time, and better understand the challenges astronauts may face. Therefore, the AU has a direct impact on fields such as astrophysics, space exploration, and the search for life on other planets.

Practical Activity - 'Understanding the Astronomical Unit: A Solar Systemic Scale'

Objective

The project aims to apply the knowledge acquired about the Astronomical Unit to build a physical scale of the solar system using accessible materials.

Project Description

Groups, consisting of 3 to 5 students, will build a scale model of the solar system, considering the distances between the planets and the Sun in Astronomical Units.

This project will last for one week, with each student dedicating two to four hours to its execution.

Necessary Materials

• A tape measure or ruler
• Styrofoam balls of different sizes
• Paint of various colors
• Paintbrushes
• Straws or barbecue sticks
• String

Step by Step

1. Start by researching the distances between the planets and the Sun in Astronomical Units (AU). NASA provides detailed information on this.

2. Based on the collected data, decide the scale of your model. For example, you can use 1 centimeter to represent 1 AU. Make the necessary calculations to know the distance in your scale between each planet and the Sun.

3. Use the Styrofoam balls to represent the planets and the Sun. Try to choose sizes proportional to the actual sizes of the planets.

4. Paint each Styrofoam ball to represent the planets and the Sun. You can use online resources to help decide which colors to use.

5. Use a straw or a barbecue stick to pierce a hole in each Styrofoam ball. Pass the string through the holes and mark the distances you calculated on each string for each planet.

6. Now your model is ready! You can use the sticks to fix the planets on a flat surface or hang them to create a mobile model of the solar system.

Project Deliverables

Students will be responsible for submitting two main deliverables:

1. The physical model of the solar system, which will be evaluated in terms of accuracy, creativity, and quality of execution.

2. A written report, which should follow the following structure:

   • Introduction: The student must contextualize the theme, its relevance and application in the real world as well as the objective of this project.

   • Development: The student must explain the theory behind the Astronomical Unit, describe the activity in detail, the methodology used, and finally present and discuss the results obtained.

   • Conclusion: The student must conclude the work by summarizing its main points, explaining the learnings obtained, and the conclusions drawn about the project.

   • Bibliography: The student must indicate the sources on which they based their work on the project such as books, web pages, videos, etc.

The practical activity and the written report will serve to assess students' understanding of the Astronomical Unit and their ability to apply this knowledge in a practical situation, as well as their teamwork, time management, communication, and creative thinking skills.