The Solar System
Learning the data
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You can always create as many flashcards as you like, free of charge.
This deck costs you nothing. You get 47 flashcards, sorted into 3 categories and with notes that add to them. You start out learning instead of typing, and whatever you find missing later you add yourself.
- Cards
- 47
- Categories
- 3
- Price
- free
Free, no account, no ads
What is in this deck
With this deck you learn the numbers of the solar system worth keeping: distances, orbital periods and sizes from the Sun to Pluto.
A day on Venus lasts longer than its year. Saturn has 146 moons, Earth has one. And Neptune needs 165 years for one lap around the Sun.
This deck asks orbital period, diameter, day length, moon count and distance for all eight planets, plus the Sun, the Moon and Pluto. Every card carries its own note, one that leads further instead of repeating the number.
The values follow NASA's Planetary Fact Sheet, which is in the public domain.
The categories decide what comes up: start with “Inner planets” alone and add the rest when you are ready.
What you learn
- Orbital period and day length of all eight planets
- Diameter, moon count and distance
- The Sun, the Moon and Pluto too
The categories
3 categories sort the 47 cards. You can filter by category and take on what is due right now.
- Inner planets
- Outer planets
- Sun, Moon and Pluto
What you get
Here are three of the 47 cards that are in this deck.
Question
How long does Mercury take to orbit the Sun?
Answer
88 days
Note
Mercury stays so close to the Sun that you only ever catch it at twilight, low over the horizon, shortly after sunset or shortly before sunrise.
Question
What is the diameter of Mercury?
Answer
4,879 km
Note
Mercury is smaller than Ganymede and Titan, the largest moons of Jupiter and Saturn. Among the planets it is still the smallest.
Question
How many moons does Mercury have?
Answer
None
Note
This close to the Sun a satellite would not stay long. The pull of the Sun outweighs the grip the planet could keep on it.
Learning with Qardbox
You see a card, you think, you turn it over and say whether you knew it. A round asks nothing more of you, and how the app works out the next date from that is on the page about FSRS-6.
What sits comes back less often, what wobbles comes back soon. You set a daily goal, and when nothing is due the app tells you exactly that instead of inventing work for you. How a round goes is shown on the learning page.
Everything stays on your device. No account, no sign-up, no ads. After the purchase the deck sits in your library like any other subject and can be studied, reordered and extended just like your own.
What it costs, and what it doesn’t
Qardbox itself costs nothing, and it stays that way. Every function is there from the start, with no subscription, no ads and no tiers; what that rests on is on the page about what it costs.
Your own cards stay unlimited, and decks from friends or from the family you read in without a limit, from a file as well. You do not need this deck in order to learn with Qardbox.
This deck costs nothing. Its 47 cards are checked and save you the work you would otherwise have.
Common questions
Do I have to pay for Qardbox?
No. The app is free, with no subscription and no ads, and every function is there. This deck is free too; some other ready-made decks cost a little, once.
Could I make these cards myself?
Yes, without limit and for free. You can type them, import a file or take over cards from friends. This deck only saves you the work.
How many cards are in The Solar System?
47 cards, sorted into 3 categories.
Do I need a connection to study?
Only to download the deck. After that it lives on your device and you study offline. There is no account, and you sign in nowhere.
Which devices does this run on?
On iPhone and iPad from iOS 26, and on Apple Watch. One purchase covers the family through Family Sharing.
Is there a Qardbox for Android?
No. Qardbox is there for iPhone, iPad and Apple Watch, not for Android and not in a browser.
Other decks that go with this one
Get started
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