Astrophysics and the Cosmic Scale
Like Duolingo, but for Astrophysics and the Cosmic Scale. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
Free forever · No credit card · iPhone & Android

Key ideas in Astrophysics and the Cosmic Scale
- Cooler gas in a star's atmosphere absorbs specific light frequencies
- Approaching objects compress light waves into higher frequencies
- Every chemical element leaves a unique 'fingerprint' of missing colors
- Receding objects stretch light waves into longer, redder wavelengths
- How specific elements are identified in a star's light
- Interpreting motion through light frequency shifts
- Wien's Law states that shorter wavelengths indicate higher energy and heat
- Blue light has more energy than red light, marking the hottest stars
- Ranking star temperatures based on their peak color
- Transparency refers to the absence of clouds, dust, or humidity
- Seeing measures image sharpness based on atmospheric turbulence
- Distinguishing between atmospheric clarity and stability
- Larger apertures collect more photons to reveal faint, distant objects
- A wider diameter reduces diffraction to show finer structural details
- The primary benefits of a larger telescope aperture
- Right Ascension and Declination are fixed to the stars, not the local horizon
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 Astrophysics and the Cosmic Scale 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.
What happens to the frequency of light when a star is rapidly approaching Earth?
Get it right to open this lesson and 29 more in the app.
Where Astrophysics and the Cosmic Scale takes you
Move beyond identifying constellations to understanding the mechanics of the universe. Explore the physics of stellar evolution, the evidence for dark matter, and the tools astronomers use to measure the edge of space.
- 1
The Observer's Toolkit
- Decoding Starlight
- Navigating the Celestial Sphere
- 2
Stellar Engines and Evolution
- The Life of a Main Sequence Star
- Stellar Death and Exotic Remnants
- 3
Galactic Architecture
- The Mechanics of the Milky Way
- Exoplanets and Other Worlds
- 4
The Dynamic Universe
- The Cosmic Distance Ladder
- Dark Energy and the Big Bang
- 5
High-Energy Phenomena
- Black Holes and Spacetime
- Gravitational Waves and Multi-Messenger Astronomy
5 sections · 10 units · 30 levels. Built to play, not to enroll.
You pick the voice
Astrophysics and the Cosmic Scale is taught in the The Professor style: clear, structured, thorough. 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.
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Start Astrophysics and the Cosmic Scale today.
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