Titan vs Mercury
Titan (5,149 km) is 1.06× the size of Mercury (4,879 km).
Mercury is 95% of the height of Titan. The gap between them is 270 km (885,827 ft).
The comparison in numbers
| Thing | Size | In feet | Measured as |
|---|---|---|---|
| Titan | 5,149 km | 16,894,357 ft | diameter |
| Mercury | 4,879 km | 16,008,530 ft | diameter |
What the scale shows
Titan (5,149 km) is 1.06× the size of Mercury (4,879 km). The gap between them is 270 km (885,827 ft). Both are planets & moons, so the figures describe the same kind of thing.
Draw both on one baseline and the smaller one fills 95% 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 Titan is its diameter (mean diameter). The figure for Mercury is its diameter (mean diameter).
Crossing them
At a jet's 900 km/h, Titan's 5,149 km would take 5.7 hours and Mercury's 4,879 km would take 5.4 hours.
In people: Titan is 3,029,059 adults of 1.7 m tall, Mercury is 2,870,235.3. By size Titan is 10th of the 16 planets & moons on this site and Mercury is 11th, so 1 place separates them in the ranking.
How to read these two figures
Before trusting any comparison, check what each number measures. Titan is given as a diameter, mean diameter. Mercury 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, Titan is number 10 from the top and Mercury is number 11. 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 1.06× is easy to picture, but area and volume grow faster than length. If two objects had exactly the same shape, Titan would have about 1.11× the surface or footprint of Mercury, and about 1.18× 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. Mercury is drawn 95% as tall as Titan, but the equivalent share of footprint would be only 89.8%, 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 Titan (5,149 km) in 17 milliseconds and Mercury (4,879 km) in 16 milliseconds. A jet at 900 km/h would take 5.7 hours for the larger and 5.4 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 1.06× ratio as the sizes.
The same figures in other units
Titan measures 5,149 km, which is 16,894,357 ft or 3,199.7 miles. Mercury measures 4,879 km, which is 16,008,530 ft or 3,031.92 miles.
The difference between them is 270 km (885,827 ft). In kilometres the smaller one is 4,879.4 against 5,149.4, so the 1.06× ratio holds in every unit; only the numbers on the ruler change.
Questions people ask about this pair
Which is bigger, Titan or Mercury?
Titan is bigger. At 5,149 km it is 1.06× the size of Mercury, which is 4,879 km.
How many times does Mercury fit along Titan?
Less than twice: Mercury is 95% of the size of Titan, so one fits with 270 km to spare.
Are the two figures measured the same way?
Yes in kind: both are diameter figures. Titan is mean diameter; Mercury is mean diameter.
How does the gap look in people?
Taking an adult of 1.7 m, Titan is about 3,029,059 people tall and Mercury is about 2,870,235.3. The gap of 270 km is 158,824 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.