What could destroy Earth's ozone layer and threaten life on the planet?

A major asteroid impact, volcanic activity, or certain atmospheric chemicals can damage ozone; the course examines cosmic and environmental threats to life on Earth.

What causes a geomagnetic storm, and how can it affect Earth?

Geomagnetic storms occur when solar wind or coronal mass ejections disturb Earth's magnetic field, potentially disrupting satellites, radio signals, GPS, and power grids.

Why is Europa considered a possible home for extraterrestrial life?

Jupiter's moon Europa likely has a salty ocean beneath its icy surface, along with energy sources and chemical ingredients that could support microbial life.

Free Course Image How the Universe works

Free online course How the Universe works

Duration of the online course: 43 minutes

4.7

(3)

Explore how the universe works and sharpen your astronomy skills in a free online course—planets, solar storms, black holes, and the search for life.

In this free course, learn about

Cosmic hazards that could threaten or destroy life on Earth
How ozone-layer damage (e.g., radiation events) could drive mass extinction
Overview of Solar System planets and key properties
Why Venus is the hottest planet despite not being closest to the Sun
Key features of Jupiter and the Great Red Spot mega-storm
How powerful solar storms form and their risks to Earth and technology
What geomagnetic storms are and how solar eruptions trigger them
Black hole basics: gravity, accretion, and spacetime effects
What an event horizon is and why nothing escapes past it
What “supermassive” black holes are and how they shape galaxies
Evidence for a Milky Way central black hole from stellar orbits and emissions
Why Sagittarius A* is accepted as a supermassive black hole candidate
Europa’s environment and why it may host a subsurface ocean
Factors that make Europa a promising candidate for extraterrestrial life

About the free online course

Take a bigger view of the night sky and learn how the universe works through a journey that connects breathtaking cosmic phenomena with real scientific reasoning. Designed for curious minds and astronomy enthusiasts, this free online course helps you build a clearer understanding of what shapes our solar system, how extreme space events unfold, and why certain cosmic threats matter for life on Earth.

You will explore the fragile balance that makes our planet habitable and the kinds of space-driven disruptions that could change it. From the behavior of the Sun to the effects of energetic events on Earth’s protective atmosphere, the course highlights how interconnected our world is with space weather. You will also develop a stronger sense of scale and perspective by examining the structure and dynamics of our solar neighborhood, refining your grasp of planetary characteristics and what makes each world unique.

As the course expands outward, it moves into some of the most fascinating and extreme objects known to science: black holes. You will learn what defines them, what happens near their boundaries, and how astronomers can infer their presence through observation and evidence rather than direct sight. The course also focuses on the supermassive black hole believed to sit at the heart of the Milky Way, offering an accessible way to understand how scientists support these conclusions using measurable signals and patterns.

To round out the experience, you will shift from cosmic hazards to cosmic possibilities by considering the search for life beyond Earth. By looking at intriguing locations such as icy moons with hidden oceans, you will understand why certain environments are promising, what conditions scientists look for, and how these discoveries could reshape our view of life in the universe.

With short assessments to reinforce key ideas, you will finish with a more confident, science-based understanding of the universe and a stronger astronomy foundation you can apply to documentaries, news, stargazing, and further learning.

Course content

Video class: How The Universe Could Destroy Life On Earth 05m
Exercise: What is estimated to potentially cause the extinction of life on Earth by directly affecting the ozone layer?
Video class: Our Solar System 2020 - Part 1 05m
Exercise: Which planet is the hottest in the solar system?
Video class: Our Solar System Documentary - Part 2 05m
Exercise: Which planet is known for its Great Red Spot, a massive storm larger than two Earths?

Video class: The Dangers of a Powerful Solar Storm 05m
Exercise: What is a geomagnetic storm and what causes it?
Video class: Black Hole Documentary 2019 - Part 1 06m
Exercise: What is the event horizon in a black hole?
Video class: Supermassive Black Hole Documentary - Part 2 05m
Exercise: What evidence supports the existence of a supermassive black hole at the center of the Milky Way?
Exercise: What evidence supports Sagittarius A* as a supermassive black hole?

Video class: Supermassive Black Hole Documentary - Part 2 05m
Exercise: What evidence supports the existence of a supermassive black hole at the center of the Milky Way?
Exercise: What evidence supports Sagittarius A* as a supermassive black hole?
Video class: Is There Alien Life on Jupiter's Moon Europa? 04m
Exercise: What makes Europa a potential candidate for hosting extraterrestrial life?

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