Course · Astronomy

Space Without Formulas: From the Moon to Black Holes

How the universe works — the solar system, the life of stars, black holes, galaxies, the Big Bang, and the search for life — without a single formula.

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Unit 1. Our backyard: the solar system

The Sun — a star on our doorstep

5 exercises · Understand that the Sun is an ordinary star, how far away it is and what it is made of, and why it is the Sun that holds the whole system together.

Eight planets and order in our home

6 exercises · Memorize the order of the planets, divide them into rocky and gaseous ones, and understand why Pluto is no longer a planet.

The Moon, the seasons, and weight on other worlds

6 exercises · Figure out why the seasons change, what weight and mass are, and why on the Moon you jump higher even though your mass stays the same.

Eclipses and tides

7 exercises · Understand how the Sun, Earth, and the Moon line up during eclipses, why eclipses are rare, and how the Moon raises the oceans.

Unit 2. The life of a star

Why stars shine and what color they are

6 exercises · Understand that stars don't “burn” but shine thanks to nuclear fusion, and that a star's color tells you its temperature.

How stars die

7 exercises · Learn the two ways a star can die — quietly (a white dwarf) and explosively (a supernova) — and understand that we are made of stardust.

Unit 3. Extreme space

Neutron stars — a thimble heavier than a mountain

4 exercises · Understand what remains after a massive star explodes and how monstrously dense matter can be.

Black holes and the event horizon

7 exercises · Understand what a black hole is, what the event horizon is, and why not even light can escape, busting the main myths along the way.

Unit 4. Galaxies and the scale of the universe

The Milky Way — our star city

4 exercises · Understand that the Sun is one of hundreds of billions of stars in the galaxy, and that there are countless galaxies in the universe.

A light-year is a time machine

6 exercises · Understand that a light-year is a measure of distance, not time, and that when we look far away, we look into the past.

Unit 5. The Big Bang

Where the universe came from

4 exercises · Understand the idea of the Big Bang and that it is space itself that expands, not fragments flying apart through emptiness.

Echo of the birth: the cosmic microwave background

6 exercises · Learn about the cosmic microwave background (CMB) — the oldest light in the universe — and understand why it is the best evidence for the Big Bang.

Unit 6. Is anyone out there?

Exoplanets and the habitable zone

6 exercises · Learn that other stars have planets of their own, what the habitable zone is, and how worlds thousands of light-years away are found at all.

How we search for life in the universe

6 exercises · Understand the real ways of searching for life — from analyzing the atmospheres of exoplanets to listening for radio signals — and take a sober look at what we have found so far.

Unit 7. Wrap-up: putting it all together

The big review: from the Moon to the edge of the universe

6 exercises · Pull everything you've learned together into one picture — the scales, the objects, and the key facts of the course — and lock in the counterintuitive truths.