Imagining Other Earths
- Free
- No certificate
- 3 weeks
Imagining Other Earths is David Spergel's Princeton course on the question of whether we are alone. It introduces core concepts from astronomy, biology and planetary science so that you can speculate scientifically about life elsewhere and invent your own solar systems. Its twenty-five short modules move from the size of the universe and the definition of life through the planets, moons and small bodies of our solar system and their atmospheres, to the search for extrasolar planets using Kepler's laws, transits, microlensing and imaging, the properties and evolution of stars, the formation of the Earth and the origin of water, the biochemistry and origin of life, extremophiles and extinctions, and finally what makes a planet habitable, the habitable zone, the Fermi paradox and SETI.
Coursera lists a flexible schedule and estimates three weeks at ten hours a week; no level is given. The page states that all the features of the course are available for free and that it does not offer a certificate upon completion.
What you’ll learn
- Describe the scale of the universe and the conditions that define life
- Compare the planets and small bodies of the solar system and their atmospheres
- Explain how extrasolar planets are found through Kepler's laws, transits and microlensing
- Relate stellar properties and evolution to habitable zones
- Summarise the origin and evolution of life on Earth and the Fermi paradox
Who it’s for
Curious general readers who want a broad science course on planets and life with short lectures and no prerequisites.
Syllabus
25 sections as listed on coursera.org, 25 h 55 min in total.
- Introduction 28 min
- The Universe is Big! 36 min
- What is Life? 29 min
- Why is Mercury Hot? 43 min
- Snowball Earth 44 min
- Planetary Atmospheres 33 min
- Mercury and Venus 1 h 11 min
- Mars 41 min
- The Moon 2 h 52 min
- Small Bodies of the Solar System 46 min
- Kepler’s Law and Search for Extrasolar Planets 1 h 27 min
- Kepler and Transits 45 min
- Einstein and the Search for Planets 1 h 5 min
- Properties of Stars 49 min
- Stellar Evolution 2 h 41 min
- Quantum Mechanics and Fingerprinting Planets 36 min
- Optics and Imaging Planets 1 h 1 min
- Formation of the Earth and the Origin of Water 46 min
- Biochemistry of Life 47 min
- Is Earth Special? Origin of Life 48 min
- Evolution of Life 54 min
- Extremophiles 1 h 45 min
- Extinctions 52 min
- What makes a Habitable Planet? 42 min
- Habitable Zone, Fermi Paradox & SETI 1 h 54 min
Instructor
- David Spergel Charles Young Professor of Astronomy on the Class of 1897 Foundation and Chair, Department of Astrophysics, Princeton University
Course details
- Skills covered
- Biochemistry
- Physics
- Biology
- Includes
- 25 modules
- Subtitles
- 22 languages
On coursera.org
Rated 4.8 out of 5 by 421 learners; 58,179 enrolled, as shown on the course page on 20 Oct 2026. These are coursera.org’s own figures, not ours.
Source: Princeton Online (opens in a new tab) · Verified · Report a change
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