The Moon vs Europa
The Moon (3,475 km) is 1.11× the size of Europa (3,122 km).
Europa is 90% of the height of the Moon. The gap between them is 353 km (1,158,793 ft).
The comparison in numbers
| Thing | Size | In feet | Measured as |
|---|---|---|---|
| The Moon | 3,475 km | 11,400,262 ft | diameter |
| Europa | 3,122 km | 10,241,470 ft | diameter |
What the scale shows
The Moon (3,475 km) is 1.11× the size of Europa (3,122 km). The gap between them is 353 km (1,158,793 ft). Both are planets & moons, so the figures describe the same kind of thing.
Draw both on one baseline and the smaller one fills 90% of the frame while the larger one runs to the top. The two are close enough that the difference is easy to see side by side.
Read the rest — 8 more sections
What each figure means
The figure for the Moon is its diameter (mean diameter). The figure for Europa is its diameter (mean diameter).
Crossing them
At a jet's 900 km/h, the Moon's 3,475 km would take 3.9 hours and Europa's 3,122 km would take 3.5 hours.
In people: the Moon is 2,044,000 adults of 1.7 m tall, Europa is 1,836,235.3. By size the Moon is 13th of the 16 planets & moons on this site and Europa is 14th, so 1 place separates them in the ranking.
How to read these two figures
Before trusting any comparison, check what each number measures. The Moon is given as a diameter, mean diameter. Europa is given as a diameter, mean diameter. Both are diameter figures, so putting them on one baseline is a like-for-like comparison, although the exact individual or convention still matters.
Worlds are listed by diameter. Gas giants are not round, so equatorial diameter is used for them and mean diameter for the rest. All figures are rounded from published mission data.
Where the pair sits among all the sizes here
Across all 86 things on this site, the Moon is number 13 from the top and Europa is number 14. No other item falls between them, so in this collection they are direct neighbours.
Because the collection spans 13 mm up to 1,392,700 km, a ratio of 107,130,769,231× from smallest to largest, the position of a pair says a lot: both sit in the upper third of the list.
What the length ratio hides
A length ratio of 1.11× is easy to picture, but area and volume grow faster than length. If two objects had exactly the same shape, the Moon would have about 1.24× the surface or footprint of Europa, and about 1.38× the volume. These two are not the same shape, so treat the figures as an upper bound for an imaginary scaled copy, not as a measurement of either one.
The drawing above shows length only. Europa is drawn 90% as tall as the Moon, but the equivalent share of footprint would be only 80.7%, which is why the smaller one looks even slighter than the numbers alone suggest.
Time to cross each one
Light travels at 299,792,458 m/s, so it crosses the Moon (3,475 km) in 12 milliseconds and Europa (3,122 km) in 10 milliseconds. A jet at 900 km/h would take 3.9 hours for the larger and 3.5 hours for the smaller.
These times assume a straight line and constant speed, which no real crossing has, but they turn a number in metres into something the body understands. At any fixed speed the travel times keep the same 1.11× ratio as the sizes.
The same figures in other units
The Moon measures 3,475 km, which is 11,400,262 ft or 2,159.1 miles. Europa measures 3,122 km, which is 10,241,470 ft or 1,939.67 miles.
The difference between them is 353 km (1,158,793 ft). In kilometres the smaller one is 3,121.6 against 3,474.8, so the 1.11× ratio holds in every unit; only the numbers on the ruler change.
Questions people ask about this pair
Which is bigger, the Moon or Europa?
The Moon is bigger. At 3,475 km it is 1.11× the size of Europa, which is 3,122 km.
How many times does Europa fit along the Moon?
Less than twice: Europa is 90% of the size of the Moon, so one fits with 353 km to spare.
Are the two figures measured the same way?
Yes in kind: both are diameter figures. The Moon is mean diameter; Europa is mean diameter.
How does the gap look in people?
Taking an adult of 1.7 m, the Moon is about 2,044,000 people tall and Europa is about 1,836,235.3. The gap of 353 km is 207,765 people.
Where do the numbers come from?
Each item has its own page that names the measurement and links to the Wikipedia article it was taken from. Some figures are rounded, and animals vary from one individual to the next, so treat them as representative values rather than records for every case.
How the sizes are taken. Each figure says what it measures — height, length, diameter or elevation — and for which individual or convention. Everything is drawn standing upright on one baseline so a single scale holds, including things that are long rather than tall. Values come from the linked Wikipedia article for each item.