Answer & explanation
The official answer, with Fermi’s reasoning step by step.
Answer & explanation
Official answer
17,600
Mars bars
How to estimate it
Fermi’s official “Napkin math”
Curiosity is about the size of a small car, but it had to be light enough to fly to Mars. How heavy is it? Maybe a ton, 2,000 pounds. Each bar is close to 2 ounces.
- Curiosity
- ~2,000 lb
- 2,000 × 16 oz
- ≈ 32,000 oz
- One bar
- ~2 oz
- 32,000 ÷ 2
- ≈ 16,000
Curiosity is about the size of a small car, but it had to be light enough to fly to Mars. How heavy is it? Maybe a tonne, 1,000 kilograms, which is 1,000,000 grams. Each bar is about 50 grams.
- Curiosity
- ~1,000 kg
- In grams
- = 1,000,000 g
- One bar
- ~50 g
- 1,000,000 ÷ 50
- ≈ 20,000
Rounded assumptions may give a slightly different estimate. The official answer above is the game’s reference value.
Source calculation & reference
- Curiosity rover mass (NASA)
- 899 kg (1,982 lb)
- One standard Mars bar
- ÷ 51 g
- 899,000 ÷ 51
- ≈ 17,600
Reference cited by Fermi: NASA Curiosity mission page (899 kg, 1,982 lb) · Mars Wrigley UK standard single bar (51 g)
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