Question 1 of 10Correct: 0
Why do you always see one side of the Moon?
Why do you see different craters at the Moon's edge over time?
Why are there two tidal bulges?
Why does the Sun affect tides less than the Moon?
Why does the Moon hardly resemble a randomly captured satellite?
What happened after Theia's impact, according to the main hypothesis?
What still works on the Moon?
Why were so many things left on the Moon?
Why does the Moon look bigger near the horizon?
How can you test this yourself?
Questions from 5 articles
Each one takes 2 minutes to read. Stuck on a question? Peek at the article.
Why the Moon always shows one facein the app0/2Why Tides Are Linked to the Moon0/2Where the Moon Came From0/2What People Left on the Moon0/2What Is the Moon Illusion?in the app0/2
A quiz after every article
In the app, a quiz like this follows every article, and every read grows your streak and level.
Answers and explanations10 questions
- Why do you always see one side of the Moon? It rotates on its axis in sync with its orbitThe Moon rotates on its axis in the same time it takes to orbit Earth, so one side faces us.From “Why the Moon always shows one face”
- Why do you see different craters at the Moon's edge over time? The Moon wobbles slightly because of its orbit and axial tiltBecause of its imperfect orbit and axial tilt, the Moon wobbles slightly, revealing details beyond its edge.From “Why the Moon always shows one face”
- Why are there two tidal bulges? The difference in pull matters: near-side water moves ahead, far-side water lags behindWater gathers on both sides of the planet, while there is less of it along the sides.From “Why Tides Are Linked to the Moon”
- Why does the Sun affect tides less than the Moon? It is far away, so the difference in pull between Earth's sides is smallerWhat matters is not the force of gravity, but its gradient, and the nearby Moon has a stronger one.From “Why Tides Are Linked to the Moon”
- Why does the Moon hardly resemble a randomly captured satellite? It is too large compared with EarthThe Moon is unusually large for Earth's satellite, and a captured body would have nowhere to lose speed in orbit.From “Where the Moon Came From”
- What happened after Theia's impact, according to the main hypothesis? Mantle debris gathered in orbit to form the MoonThe glancing impact threw material from Earth's upper layers into orbit, and the Moon formed from the glowing debris.From “Where the Moon Came From”
- What still works on the Moon? Corner-cube reflectorsThey need no power: they simply return the laser beam exactly where it came from.From “What People Left on the Moon”
- Why were so many things left on the Moon? Every kilogram at takeoff required fuelBefore takeoff, they dumped everything they could just to lift the rock samples and people.From “What People Left on the Moon”
- Why does the Moon look bigger near the horizon? It is a perceptual illusion with no single explanationIts angular size is even slightly smaller near the horizon: it is farther away by one Earth radius there.From “What Is the Moon Illusion?”
- How can you test this yourself? Look through a rolled-up tube - the effect will disappearBy removing the surroundings from your field of view, you see the true size.From “What Is the Moon Illusion?”