How Space Works
Understand what you see when you look up at the night sky and how the cosmos functions. Learn the mechanics of orbits, the lifecycle of stars, and the vast architecture of the universe.
Like Duolingo, but for How Space Works. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
19 levels across 3 sections, about 38 minutes end to end, roughly 8 days at five minutes a day. It moves through Observing the Night Sky, The Solar System and Spaceflight, and The Deep Cosmos. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in How Space Works
- A steady, non-flickering bright light in the night sky is almost always a planet rather than a star
- Stars appear as microscopic pinpoints of light easily disrupted and scattered by moving air currents in Earth's atmosphere
- Planets are closer and appear as tiny wide discs that average out atmospheric blurring, keeping their light steady
- All planets orbit the Sun on roughly the same flat geometric plane
- From Earth, planets only ever track along a single narrow highway across the sky called the ecliptic, sharing the Sun and Moon's path
- You will never find a planet far to the north or scattered randomly outside this specific track
- Satellites shine by reflecting sunlight down to Earth while orbiting high above Earth's shadow
- Airplanes flash colored navigation lights and make engine noise, while satellites are completely silent with an unblinking, constant glow
- Satellites take several minutes to glide smoothly across the sky, unlike meteors which streak and vanish in seconds
- Shooting stars are not stars dropping from space, but tiny grains of rock and dust burning up in Earth's atmosphere
- The friction and heat from hitting the upper atmosphere at high speed makes the surrounding air glow into a momentary streak
- Most meteors are microscopic debris shed by passing comets
- How bright a celestial object looks from Earth depends on two factors: how much light it actually produces and how far away it is
- Distance dramatically dilutes incoming starlight before it reaches human eyes
- A dimmer, smaller star located close to our solar system can easily outshine an immense supergiant star that sits thousands of light-years away
- One half of the Moon is always lit by the Sun, just like Earth
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives How Space Works the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
You look up at the night sky and see a bright point of light that shines steadily without flickering. What are you most likely seeing?
Get it right to open this lesson and 18 more in the app.
Where How Space Works takes you
- 1
Observing the Night Sky
- Spotting Objects with the Naked Eye
- Tracking Cosmic Rhythms from Earth
- 2
The Solar System and Spaceflight
- Understanding the Planetary Neighborhood
- The Rules of Space Travel
- 3
The Deep Cosmos
- How Stars Live and Die
- Galaxies and the Expanding Universe
3 sections · 6 units · 19 levels. Built to play, not to enroll.
You pick the voice
How Space Works is taught in the The Bestie style: your friend who just gets it. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
More Science on Tomo
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Start How Space Works today.
Download Tomo, search How Space Works, and play your first lesson in under a minute.