Section 2: Understanding the Universe

The universe is a vast and complex place, and understanding it can be a bit overwhelming. But, by taking notes and going step-by-step, you can learn a lot about the galaxies, stars, and other celestial bodies that make up our universe. That's why we've created this note-taking worksheet to help you explore and understand the stars and galaxies.

What is the Big Bang Theory?

The Big Bang Theory is the most widely accepted explanation for the origin of the universe. It states that the universe began in an extremely hot and dense state, which then rapidly expanded and cooled. This sudden expansion is what created the universe we know today.

What is the Milky Way?

The Milky Way is the name of our galaxy. It is home to the Sun and all of the planets in our Solar System. It is a spiral-shaped galaxy, and it is estimated to contain between 200 and 400 billion stars. It is estimated to be about 13.2 billion years old.

What is a Star?

A star is a huge ball of gas held together by its own gravity. Stars are composed primarily of hydrogen and helium, and they generate heat and light through nuclear fusion. They come in a variety of sizes, colors, and temperatures, and can live for billions of years.

What is a Galaxy?

A galaxy is a collection of stars, gas, and dust held together by its own gravity. Galaxies come in a variety of shapes and sizes, and they can contain anywhere from a few hundred to a few hundred billion stars. Our own Milky Way is an example of a spiral-shaped galaxy.