Unit E: Space Exploration

Key Ideas     Unit Checklist 

Pre-assessment: What do you know?



Figure E.P.1 – Living in space is challenging for humans.

Figure E.P.2 – Modern societies use spacecraft for communication technologies.


Figure E.P.3 – Earth is located in the Milky Way galaxy.
For millions of years, humans have observed distant objects in the sky. Aboriginal cultures around the world carefully observed the changing positions of the Moon, the Sun, stars, and planets.

Human understanding of space has greatly increased in the last 500 years, after the invention of the telescope. Ongoing improvements in telescope design allows us to continue deepening our knowledge of the universe. We can collect light and radio waves from distant places in space. From these observations, scientists have concluded that new stars and planets continue to form.

Since the mid-1900s, humans have sent spacecraft and astronauts into space. Today, many modern communication technologies depend on space satellites. Astronauts make observations about space and Earth. However, keeping people alive in space is challenging. This is why scientists have used robotic spacecraft to explore the solar system, instead of sending people to other planets.

What do you know about space exploration? What are the risks and benefits to exploring space?

To learn more about how we can increase human space exploration, we must understand the characteristics of space and the challenges of sending humans and spacecraft to space.


Figure E.P.4 – Rockets require lots of energy to launch.

Figure E.P.5 – Telescopes allow people to view distant stars.

Pre-assessment Questions & Hints

Step 1: The Questions


This short pre-assessment is to find out what you might already know about the topic of . Below are four questions. Think about them! If you need a hint, click on the question.

Optional: If you would like a place to write your answers, download this document. If you prefer to use a Google Drive or PDF version of this pre-assessment, click here.
Think about how the energy coming from the Sun reaches the Earth.
Think about substances that cause reflection and refraction of light.
Think about dangerous things that can happen while people travel in space.

Step 2: The Answers

 Click each of the suggested answers below – how do they compare to your thoughts and answers?ο»Ώ

Fusion creates energy in the Sun and stars. In fusion, hydrogen atoms join together to make helium atoms. Lots of energy, including light and heat, are released in the process.
A spacecraft that allows humans to survive in space must contain all the substances necessary to sustain human life. For example, spacecraft must:
  • Supply oxygen to breathe in. The spacecraft must also remove waste carbon dioxide that humans breathe out.
  • Contain water for drinking and washing. Spacecraft have water-recycling systems for human urine.
  • Have methods of containing human waste.
  • Carry enough food for humans.
  • Protect from the Sun’s high energy particles.
  • Provide heat because space is very cold.
Reflecting telescopes use mirrors to magnify and focus light from distant stars. Refracting telescopes use lenses to magnify and focus light from distant stars. Radio telescopes collect radio waves from distant parts of the universe.
Travelling in space has many risks. For example:
  • Spacecraft can catch on fire leaving Earth’s atmosphere, due to explosive rocket fuels.
  • Spacecraft can catch on fire reentering Earth’s atmosphere, due to high heat generated by friction.
  • If a problem happens on a spacecraft, there is nobody besides the astronauts who can quickly arrive to fix the problem.

Step 3: Check In With Your Teacher

The start of a new unit is a great time to touch base with your teacher! Here are just a few reasons to consider contacting your teacher:

  1. Perhaps you found this pre-assessment quiz very easy because you have studied this material before, such as at another school. If so, it's important to tell your teacher.

  2. It's very good for your teacher to know you are starting a new unit; it will give them a good idea of your progress. It doesn't have to be a long message, just a "I'm starting Unit A; just thought you might want to know!"

  3. Your teacher may have special tips and suggestions for the unit you are starting.

  4. Just to say hi – your teacher always enjoys hearing from you!

To contact your teacher, post in the Course Questions Forum, send your teacher an email, or call on the phone if you like. Whatever way you choose, it's always a good idea to get in touch with your teacher – make sure you do it frequently.