Orders of magnitude (length) explained
The following are examples of orders of magnitude for different lengths.
Overview
Scale | Range (m) | Unit | Example items |
---|
≥ | < |
---|
Subatomic | – | 0 | – | Gravitational singularity |
10−36 | 10−33 | | Fixed value (not a range). Quantum foam, string |
10−18 | 10−15 | | proton, neutron, pion |
| | 10−12 | | Atomic nucleus |
| 10−9 | | Wavelength of gamma rays and X-rays, hydrogen atom |
| 10−6 | | DNA helix, virus, wavelength of optical spectrum, transistors used in CPUs |
| | 10−3 | | Bacterium, fog water droplet, human hair's diameter[1] |
| 1 | | Mosquito, golf ball, domestic cat, violin, football |
| 1 | 103 | | Piano, human, automobile, sperm whale, football field, Eiffel Tower |
| 106 | | Mount Everest, length of Panama Canal and Trans-Siberian Railway, larger asteroid |
| | 109 | | The Moon, Earth, one light-second |
| 1012 | | Sun, one light-minute, Earth's orbit |
| 1015 | | Orbits of outer planets, Solar System |
| 1018 | | A light-year, the distance to Proxima Centauri |
| 1021 | | Galactic arm |
| 1024 | | Milky Way, distance to Andromeda Galaxy |
| 1027 | | Huge-LQG, Hercules–Corona Borealis Great Wall, Observable universe | |
Detailed list
To help compare different orders of magnitude, the following list describes various lengths between
metres and
metres.
Subatomic scale
Atomic to cellular scale
Cellular to human scale
Factor (m) | Multiple | Value | Item |
---|
10−6 | 1 micrometre (μm)(also called 1 micron) | 1–4 μm | Typical length of a bacterium[23] |
4 μm | Typical diameter of spider silk[24] |
7 μm | Typical size of a red blood cell[25] |
10−5 | 10 μm | 10 μm | Typical size of a fog, mist, or cloud water droplet |
10 μm | Width of transistors in the Intel 4004, the world's first commercial microprocessor |
12 μm | Width of acrylic fiber |
17-181 μm | Width range of human hair[26] |
10−4 | 100 μm | 340 μm | Size of a pixel on a 17-inch monitor with a resolution of 1024×768 |
560 μm | Thickness of the central area of a human cornea[27] |
750 μm | Maximum diameter of Thiomargarita namibiensis, the largest bacterium ever discovered |
10−3 | 1 millimetre (mm) | ~5 mm | Length of an average flea is 1–10 mm (usually <5 mm)[28] |
2.54 mm | One-tenth inch; distance between pins in DIP (dual-inline-package) electronic components |
5.70 mm | Diameter of the projectile in 5.56×45mm NATO ammunition |
10−2 | 1 centimetre (cm) | 20 mm | Approximate width of an adult human finger |
54 mm × 86 mm | Dimensions of a credit card, according to the ISO/IEC 7810 ID-1 standard |
73–75 mm | Diameter of a baseball, according to Major League Baseball guidelines[29] |
10−1 | 1 decimetre (dm) | 120 mm | Diameter of a compact disc |
660 mm | Length of the longest pine cones, produced by the sugar pine[30] |
900 mm | Average length of a rapier, a fencing sword[31] | |
Human to astronomical scale
Factor (m) | Multiple | Value | Item |
---|
1 (100) | 1 metre (m) | 1 m (exactly) | Since 2019, defined as the length of the path travelled by light in a vacuum during a time interval of 1/299,792,458 of a second, where the second is defined by a hyperfine transition frequency of caesium. |
2.72 m | Height of Robert Wadlow, tallest-known human.[32] |
8.38 m | Length of a London bus (AEC Routemaster) |
101 | 1 decametre (dam) | 33 m | Length of the longest-known blue whale[33] |
52 m | Height of the Niagara Falls[34] |
93.47 m | Height of the Statue of Liberty |
102 | 1 hectometre (hm) | 105 m | Length of a typical football field |
137 m (147 m) | Height (present and original) of the Great Pyramid of Giza |
300 m | Height of the Eiffel Tower, one of the famous monuments of Paris |
979 m | Height of the Salto Angel, the world's highest free-falling waterfall (Venezuela) |
103 | 1 kilometre (km) | 2.3 km | Length of the Three Gorges Dam, the largest dam in the world[35] [36] |
3.1 km | Narrowest width of the Strait of Messina, separating Italy and Sicily |
8.848 km | Height of Mount Everest, the highest mountain on Earth |
104 | 10 km< | -- a.k.a. the obsolete term myriametre --> | 10.9 km | Depth of the Challenger Deep in the Mariana Trench, the deepest-known point on Earth's surface |
---|
27 km | Circumference of the Large Hadron Collider, the largest and highest energy particle accelerator |
42.195 km | Length of a marathon |
105 | 100 km | 100 km | The distance the IAU considers to be the limit to space, called the Karman line |
163 km | Length of the Suez Canal, connecting the Mediterranean Sea to the Red Sea |
491 km | Length of the Pyrenees, the mountain range separating Spain and France |
974.6 km | Greatest diameter of the dwarf planet Ceres.[37] |
106 | 1 megametre (Mm) | 2.38 Mm | Diameter of dwarf planet Pluto, formerly the smallest planet category[38] in the Solar System |
3.48 Mm | Diameter of the Moon |
5.2 Mm | Typical distance covered by the winner of the 24 Hours of Le Mans automobile endurance race |
6.259 Mm | Length of the Great Wall of China |
6.371 Mm | Average radius of Earth |
6.378 Mm | Equatorial radius of Earth |
6.6 Mm | Approximate length of the two longest rivers, the Nile and the Amazon |
7.821 Mm | Length of the Trans-Canada Highway |
9.288 Mm | Length of the Trans-Siberian Railway, longest in the world | |
Astronomical scale
Factor (m) | Multiple | Value | Item |
---|
107 | 10 Mm | 12.756 Mm | Equatorial diameter of Earth |
20.004 Mm | Length of a meridian on Earth (distance between Earth's poles along the surface)[39] |
40.075 Mm | Length of Earth's equator |
108 | 100 Mm | 142.984 Mm | Diameter of Jupiter |
299.792 Mm | Distance traveled by light in vacuum in one second (a light-second, exactly 299,792,458 m by definition of the speed of light) |
384.4 Mm | Moon's orbital distance from Earth |
109 | 1 gigametre (Gm) | 1.39 Gm | Diameter of the Sun |
5.15 Gm | Greatest mileage ever recorded by a car (3.2 million miles by a 1966 Volvo P-1800S)[40] |
1010 | 10 Gm | 18 Gm | Approximately one light-minute |
1011 | 100 Gm | 150 Gm | 1 astronomical unit (au); mean distance between Earth and Sun |
1012 | 1 terametre (Tm) | 1.3 Tm | Optical diameter of Betelgeuse |
1.4 Tm | Orbital distance of Saturn from Sun |
2 Tm | Estimated optical diameter of VY Canis Majoris, one of the largest-known stars |
5.9 Tm | Orbital distance of Pluto from the Sun |
~ 7.5 Tm | Outer boundary of the Kuiper belt |
1013 | 10 Tm | | Diameter of the Solar System as a whole |
16.09 Tm | Total length of DNA molecules in all cells of an adult human body[41] |
21.49 Tm | Distance of the Voyager 1 spacecraft from Sun, the farthest man-made object so far[42] |
62.03 Tm | Estimated radius of the event horizon of the supermassive black hole in NGC 4889, the largest-known black hole to date |
1014 | 100 Tm | 180 Tm | Size of the debris disk around the star 51 Pegasi[43] |
1015 | 1 petametre (Pm) | ~7.5 Pm | Supposed outer boundary of the Oort cloud (~ 50,000 au) |
9.461 Pm | Distance traveled by light in vacuum in one year; at its current speed, Voyager 1 would need 17,500 years to travel this distance |
1016 | 10 Pm | 30.857 Pm | 1 parsec |
39.9 Pm | Distance to nearest star (Proxima Centauri) |
41.3 Pm | As of March 2013, distance to nearest discovered extrasolar planet (Alpha Centauri Bc) |
1017 | 100 Pm | 193 Pm | As of October 2010, distance to nearest discovered extrasolar planet with potential to support life as presently defined by science (Gliese 581 d) |
615 Pm | Approximate radius of humanity's radio bubble, caused by high-power TV broadcasts leaking through the atmosphere into outer space |
1018 | 1 exametre (Em) | 1.9 Em | Distance to nearby solar twin (HIP 56948), a star with properties virtually identical to the Sun[44] |
1019 | 10 Em | 9.46 Em | Average thickness of Milky Way Galaxy[45] (1,000 to 3,000 ly by 21 cm observations[46]) |
1020 | 100 Em | 113.5 Em | Thickness of Milky Way Galaxy's gaseous disk[47] |
1021 | 1 zettametre (Zm) |
1.54 Zm | Distance to SN 1987A, the most recent naked eye supernova |
1.62 Zm | Distance to the Large Magellanic Cloud (a dwarf galaxy orbiting the Milky Way) |
1.66 Zm | Distance to the Small Magellanic Cloud (another dwarf galaxy orbiting the Milky Way) |
1.9 Zm | Diameter of galactic disk of Milky Way Galaxy[48] [49] [50] [51] |
6.15 Zm | Diameter of the low surface brightness disc halo of the giant spiral galaxy Malin 1 |
1022 | 10 Zm | 13.25 Zm | Radius of the diffuse stellar halo of IC 1101, one of the largest-known galaxies |
24 Zm | Distance to Andromeda Galaxy |
30.857 Zm | 1 megaparsec |
50 Zm | Diameter of Local Group of galaxies |
1023 | 100 Zm | 300–600 Zm | Distance to Virgo cluster of galaxies |
1024 | 1 yottametre (Ym) | 2.19 Ym | Diameter of the Local Supercluster and the largest voids and filaments |
2.8 Ym | End of Greatness |
~5 Ym | Diameter of the Horologium Supercluster[52] |
9.461 Ym | Diameter of the Pisces–Cetus Supercluster Complex, the supercluster complex which includes Earth |
1025 | 10 Ym | 13 Ym | Length of the Sloan Great Wall, a giant wall of galaxies (galactic filament)[53] |
30.857 Ym | 1 gigaparsec |
37.84 Ym | Length of the Huge-LQG, a group of 73 quasars |
1026 | 100 Ym | 95 Ym | Estimated light travel distance to certain quasars. Length of the Hercules–Corona Borealis Great Wall, a colossal wall of galaxies, the largest and the most massive structure in the observable universe as of 2014 |
127 Ym | Estimated light travel distance to GN-z11, the most distant object ever observed |
870 Ym | Approximate diameter (comoving distance) of the visible universe |
1027 | 1 Rm | 1.2 Rm | Lower bound of the (possibly infinite) radius of the universe, if it is a 3-sphere, according to one estimate using the WMAP data at 95% confidence[54] It equivalently implies that there are at minimum 21 particle horizon-sized volumes in the universe. |
3.8 Rm | Lower bound of the homogeneous universe derived from the Planck spacecraft[55] --> |
[56] |
m |
m | According to the laws of probability, the distance one must travel until one encounters a volume of space identical to our observable universe with conditions identical to our own.[57] [58] |
|
m |
m | Minimal size of universe after cosmological inflation, implied by one resolution of the No-Boundary Proposal[59] | |
1 quectometre and less
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists lengths shorter than 10−30 m (1 qm).
- 1.6 × 10−5 quectometres (1.6 × 10−35 metres) – the Planck length (Measures of distance shorter than this do not make physical sense, according to current theories of physics.)
- 1 qm – 1 quectometre, the smallest named subdivision of the metre in the SI base unit of length, one nonillionth of a metre.
1 rontometre
The (SI symbol: ) is a unit of length in the metric system equal to .
- 1 rm – 1 rontometre, a subdivision of the metre in the SI base unit of length, one octillionth of a metre.
10 rontometres
1 yoctometre
The (SI symbol: ) is a unit of length in the metric system equal to .
1 zeptometre
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists lengths between 10−21 m and 10−20 m (1 zm and 10 zm).
- 2 zm – the upper bound for the width of a cosmic string in string theory.
- 2 zm – radius of effective cross section for a 20 GeV neutrino scattering off a nucleon
- 7 zm – radius of effective cross section for a 250 GeV neutrino scattering off a nucleon
10 zeptometres
To help compare different orders of magnitude, this section lists lengths between 10−20 m and 10−19 m (10 zm and 100 zm).
100 zeptometres
To help compare different orders of magnitude, this section lists lengths between 10−19 m and 10−18 m (100 zm and 1 am).
1 attometre
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists lengths between 10−18 m and 10−17 m (1 am and 10 am).
10 attometres
To help compare different orders of magnitude, this section lists lengths between 10−17 m and 10−16 m (10 am and 100 am).
100 attometres
To help compare different orders of magnitude, this section lists lengths between 10−16 m and 10−15 m (100 am and 1 fm).
- 831 am – approximate proton radius[62]
1 femtometre (or 1 fermi)
The (SI symbol: ) is a unit of length in the metric system equal to . In particle physics, this unit is sometimes called a , also with abbreviation "fm". To help compare different orders of magnitude, this section lists lengths between 10−15 metres and 10−14 metres (1 femtometre and 10 fm).
10 femtometres
To help compare different orders of magnitude, this section lists lengths between 10−14 m and 10−13 m (10 fm and 100 fm).
100 femtometres
To help compare different orders of magnitude, this section lists lengths between 10−13 m and 10−12 m (100 fm and 1 pm).
- 570 fm – typical distance from the atomic nucleus of the two innermost electrons (electrons in the 1s shell) in the uranium atom, the heaviest naturally-occurring atom
1 picometre
The (SI symbol: pm) is a unit of length in the metric system equal to . To help compare different orders of magnitude this section lists lengths between 10−12 and 10−11 m (1 pm and 10 pm).
10 picometres
To help compare different orders of magnitude this section lists lengths between 10−11 and 10−10 m (10 pm and 100 pm).
100 picometres
To help compare different orders of magnitude this section lists lengths between 10−10 and 10−9 m (100 pm and 1 nm; 1 Å and 10 Å).
1 nanometre
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists lengths between 10−9 and 10−8 m (1 nm and 10 nm).
10 nanometres
To help compare different orders of magnitude this section lists lengths between 10−8 and 10−7 m (10 nm and 100 nm).
100 nanometres
To help compare different orders of magnitude, this section lists lengths between 10−7 and 10−6 m (100 nm and 1 μm).
- 100 nm – greatest particle size that can fit through a surgical mask[71]
- 100 nm – 90% of particles in wood smoke are smaller than this.
- 120 nm – greatest particle size that can fit through a ULPA filter[72]
- 120 nm – diameter of a human immunodeficiency virus (HIV)[73]
- 120 nm – approximate diameter of SARS-CoV-2[74]
- 125 nm – standard depth of pits on compact discs (width: 500 nm, length: 850 nm to 3.5 μm)
- 180 nm – typical length of the rabies virus
- 200 nm – typical size of a Mycoplasma bacterium, among the smallest bacteria
- 300 nm – greatest particle size that can fit through a HEPA (high efficiency particulate air) filter (N100 removes up to 99.97% at 300 nm, N95 removes up to 95% at 300 nm)[75]
- 300–400 nm – near ultraviolet wavelength*400–420 nm – wavelength of violet light (see Color and Visible spectrum)
- 420–440 nm – wavelength of indigo light
- 440–500 nm – wavelength of blue light
- 500–520 nm – wavelength of cyan light
- 520–565 nm – wavelength of green light
- 565–590 nm – wavelength of yellow light
- 590–625 nm – wavelength of orange light
- 625–700 nm – wavelength of red light
- 700–1.4 μm – wavelength of near-infrared radiation
1 micrometre (or 1 micron)
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists some items with lengths between 10−6 and 10−5 m (between 1 and 10 micrometres, or μm).
10 micrometres
To help compare different orders of magnitude, this section lists lengths between 10−5 m and 10−4 m (10 μm and 100 μm).
100 micrometres
To help compare different orders of magnitude, this section lists lengths between 10−4 m and 10−3 m (100 μm and 1 mm). The term myriometre (abbr. mom, equivalent to 100 micrometres; frequently confused with the myriametre, 10 kilometres)[89] is deprecated; the decimal metric prefix myrio- is obsolete and was not included among the prefixes when the International System of Units was introduced in 1960.
- 100 μm – 1/10 of a millimetre
- 100 μm – 0.00394 inches
- 100 μm – smallest distance that can be seen with the naked eye
- 100 μm – average diameter of a strand of human hair[26]
- 100 μm – thickness of a coat of paint
- 100 μm – length of a dust particle
- 120 μm – the geometric mean of the Planck length and the diameter of the observable universe:
- 120 μm – diameter of a human ovum
- 170 μm – length of the largest sperm cell in nature, belonging to the Drosophila bifurca fruit fly[90] [91]
- 181 μm – maximum width of a strand of human hair[26]
- 100–400 μm – length of Demodex mites living in human hair follicles
- 175–200 μm – typical thickness of a solar cell.
- 200 μm – typical length of Paramecium caudatum, a ciliate protist
- 200 μm – nominal width of the smallest commonly available mechanical pencil lead (0.2 mm)
- 250–300 μm – length of a dust mite[92]
- 340 μm – length of a pixel on a 17-inch monitor with a resolution of 1024×768
- 500 μm – typical length of Amoeba proteus, an amoeboid protist
- 500 μm – MEMS micro-engine[93]
- 500 μm – average length of a grain of sand
- 500 μm – average length of a grain of salt
- 500 μm – average length of a grain of sugar
- 560 μm – thickness of the central area of a human cornea[27]
- 750 μm – diameter of a Thiomargarita namibiensis, the largest bacteria known[94]
- 760 μm – thickness of an identification card
1 millimetre
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists lengths between 10−3 m and 10−2 m (1 mm and 1 cm).
- 1.0 mm – 1/1,000 of a metre
- 1.0 mm – 0.03937 inches or 5/127 (exactly)
- 1.0 mm – side of a square of area 1 mm²
- 1.0 mm – diameter of a pinhead
- 1.5 mm – average length of a flea[28]
- 2.54 mm – distance between pins on old dual in-line package (DIP) electronic components
- 5 mm – length of an average red ant
- 5 mm – diameter of an average grain of rice
- 5.56×45mm NATO – standard ammunition size
- 6 mm – approximate width of a pencil
- 7 mm – length of a Paedophryne amauensis, the smallest-known vertebrate[95]
- 7.1 mm – length of a sunflower seed
- 7.62×51mm NATO – common military ammunition size[96]
- 8 mm – width of old-format home movie film
- 8 mm – length of a Paedocypris progenetica, the smallest-known fish[97]
1 centimetre
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists lengths between 10−2 m and 10−1 m (1 cm and 1 dm).
- 1 cm – 10 millimetres
- 1 cm – 0.39 inches
- 1 cm – edge of a square of area 1 cm2
- 1 cm – edge of a cube of volume 1 mL
- 1 cm – length of a coffee bean
- 1 cm – approximate width of average fingernail
- 1.2 cm – length of a bee
- 1.2 cm – diameter of a die
- 1.5 cm – length of a very large mosquito
- 1.6 cm – length of a Jaragua Sphaero, a very small reptile
- 1.7 cm – length of a Thorius arboreus, the smallest salamander[98]
- 2 cm – approximate width of an adult human finger
- 2.54 cm – 1 inch
- 3.08568 cm – 1 attoparsec
- 3.4 cm – length of a quail egg[99]
- 3.5 cm – width of film commonly used in motion pictures and still photography
- 3.78 cm – amount of distance the Moon moves away from Earth each year[100]
- 4.3 cm – minimum diameter of a golf ball[101]
- 5 cm – usual diameter of a chicken egg
- 5 cm – height of a hummingbird, the smallest-known bird
- 5.08 cm – 2 inches,
- 5.5 × 5.5 × 5.5 cm – dimensions of a 3x3x3 Rubik's cube
- 6.1 cm – average height of an apple
- 7.3–7.5 cm – diameter of a baseball[29]
- 8.6 cm × 5.4 cm – dimensions of a standard credit card (also called CR80)[102]
- 9 cm – length of a speckled padloper, the smallest-known turtle
1 decimetre
The (SI symbol: ) is a unit of length in the metric system equal to . To help compare different orders of magnitude, this section lists lengths between 10 centimetres and 100 centimetres (10−1 metre and 1 metre).
Conversions
10 centimetres (abbreviated to 10 cm) is equal to:
Wavelengths
Human-defined scales and structures
- 10.16 cm = 1.016 dm – 1 hand used in measuring height of horses (4 inches)
- 12 cm = 1.2 dm – diameter of a compact disc (CD) (= 120 mm)
- 15 cm = 1.5 dm – length of a Bic pen with cap on
- 22 cm = 2.2 dm – diameter of a typical association football (soccer ball)
- 30 cm = 3 dm – typical school-use ruler length (= 300 mm)
- 30.48 cm = 3.048 dm – 1 foot (measure)
- 60 cm = 6 dm – standard depth (front to back) of a domestic kitchen worktop in Europe (= 600 mm)
- 90 cm = 9 dm – average length of a rapier, a fencing sword[31]
- 91.44 cm = 9.144 dm – one yard (measure)
Nature
- 10 cm = 1 dm – diameter of the human cervix upon entering the second stage of labour
- 11 cm = 1.1 dm – diameter of an average potato in the US
- 13 cm = 1.3 dm – body length of a Goliath birdeater
- 15 cm = 1.5 dm – approximate size of largest beetle species
- 19 cm = 1.9 dm – length of a banana
- 26.3 cm = 2.6 dm – length of average male human foot
- 29.98 cm = 2.998 dm – distance light in vacuum travels in one nanosecond
- 30 cm = 3.0 dm – maximum leg length of a Goliath birdeater
- 31 cm = 3.1 dm – wingspan of largest butterfly species Ornithoptera alexandrae
- 32 cm – length of the Goliath frog, the world's largest frog
- 46 cm = 4.6 dm – length of an average domestic cat
- 50 to 65 cm = 5–6.5 dm – a coati's tail
- 66 cm = 6.6 dm – length of the longest pine cones (produced by the sugar pine[103])
Astronomical
- 84 cm = 8.4 dm – approximate diameter of 2008 TS26, a meteoroid
1 metre
To help compare different orders of magnitude, this section lists lengths between one metre and ten metres.Light, in vacuum, travels 1 metre in, or of a second.
Conversions
1 metre is:
Human-defined scales and structures
- 1 m – approximate height of the top part of a doorknob on a door
- 1 m – diameter of a very large beach ball
- 1.29 m – length of the Cross Island Chapel, the smallest church in the world
- 1.4 m – length of an Peel P50, the world's smallest car
- 1.435 m – standard gauge of railway track used by about 60% of railways in the world = 4 ft 8 in
- 2.5 m – distance from the floor to the ceiling in an average residential house[104]
- 2.7 m – length of the Starr Bumble Bee II, the smallest plane
- 2.77–3.44 m – wavelength of the broadcast radio FM band 87–108 MHz
- 3.05 m – the length of an old Mini
- 8 m – length of the Tsar Bomba, the largest bomb ever detonated
- 8.38 m – the length of a London Bus (AEC Routemaster)
Sports
- 2.44 m – height of an association football goal
- 2.45 m – highest high jump by a human (Javier Sotomayor)
- 3.05 m – (10 feet) height of the basket in basketball
- 8.95 m – longest long jump by a human (Mike Powell)
Nature
- 1.15 m – a pizote (mammal)
- 1.5 m – height of an okapi
- 1.63 m – (5 feet 4 inches) (or 64 inches) – height of average U.S. female human (source: U.S. Centers for Disease Control and Prevention (CDC))
- 1.75 m – (5 feet 8 inches) – height of average U.S. male human (source: U.S. CDC as per female above)
- 2.4 m – wingspan of a mute swan
- 2.5 m – height of a sunflower
- 2.7 m – length of a leatherback sea turtle, the largest living turtle
- 2.72 m – (8 feet 11 inches) – tallest-known human (Robert Wadlow)[32]
- 3 m – length of a giant Gippsland earthworm
- 3.63 m – the record wingspan for living birds (a wandering albatross)
- 3.7 m – leg span of a Japanese spider crab
- 3.7 m – length of a southern elephant seal, the largest living pinniped
- 5 m – length of an elephant
- 5.2 m – height of a giraffe
- 5.5 m – height of a Baluchitherium, the largest land mammal ever lived
- 6.5 m – wingspan of Argentavis, the largest flying bird known
- 6.7 m – length of a Microchaetus rappi
- 7.4 m – wingspan of Pelagornis, the bird with longest wingspan ever.[105]
- 7.5 m – approximate length of the human gastrointestinal tract
Astronomical
- 3–6 m – approximate diameter of, a meteoroid
- 4.1 m – diameter of 2008 TC3, a small asteroid that flew into the Earth's atmosphere on 7 October 2008[106]
1 decametre
The (SI symbol: ) is a unit of length in the metric system equal to 10 metres (101 m). To help compare different orders of magnitude, this section lists lengths between 10 and 100 metres.
Conversions
10 metres (very rarely termed a decametre which is abbreviated as dam) is equal to:
Human-defined scales and structures
- 10 metres – wavelength of the highest shortwave radio frequency, 30 MHz
- 10.2 metres – length of the Panzer VIII Maus, the world's largest tank
- 12 metres- height of the Newby-McMahon Building, the world's littlest skyscraper
- 23 metres – height of Luxor Obelisk, located in the Place de la Concorde, Paris, France
- 25 metres – wavelength of the broadcast radio shortwave band at 12 MHz
- 29 metres – height of the Savudrija Lighthouse
- 30 metres – height of Christ the Redeemer 31 metres – wavelength of the broadcast radio shortwave band at 9.7 MHz
- 32 metres – length of one arcsecond of latitude on the surface of the Earth
- 33.3 metres – height of the De Noord, the tallest windmill in the world
- 34 metres – height of the Split Point Lighthouse in Aireys Inlet, Victoria, Australia
- 40 metres – wingspan of the Mil Mi-26, the largest helicopter
- 40 metres – average depth beneath the seabed of the Channel tunnel
- 49 metres – wavelength of the broadcast radio shortwave band at 6.1 MHz
- 50 metres – length of a road train
- 50 metres – height of the Arc de Triomphe
- 55 metres – height of the Leaning Tower of Pisa
- 62 metres – wingspan of Concorde
- 62.5 metres – height of Pyramid of Djoser
- 64 metres – wingspan of a Boeing 747-400
- 69 metres – wingspan of an Antonov An-124 Ruslan
- 70 metres – length of the Bayeux Tapestry
- 70 metres – width of a typical association football field
- 73 metres – wingspan of a Airbus A380
- 73 metres – height of the Taj Mahal
- 77 metres – wingspan of a Boeing 747-8
- 88.4 metres – wingspan of an Antonov An-225 Mriya transport aircraft
- 93 metres – height of the Statue of Liberty (Liberty Enlightening the World)
- 96 metres – height of Big Ben
- 100 metres – wavelength of the lowest shortwave radio frequency, 3 MHz
Sports
- 11 metres – approximate width of a doubles tennis court
- 15 metres – width of a standard FIBA basketball court
- 15.24 metres – width of an NBA basketball court (50 feet)
- 18.44 metres – distance between the front of the pitcher's rubber and the rear point of home plate on a baseball field (60 feet, 6 inches)[107]
- 20 metres – length of cricket pitch (22 yards)[108]
- 27.43 metres – distance between bases on a baseball field (90 feet)
- 28 metres – length of a standard FIBA basketball court
- 28.65 metres – length of an NBA basketball court (94 feet)
- 49 metres – width of an American football field (53 yards)
- 59.436 metres – width of a Canadian football field (65 yards)
- 70 metres – typical width of an association football field
- 91 metres – length of an American football field (100 yards, measured between the goal lines)
Nature
- 10 metres – average length of human digestive tract
- 12 metres – height of a saguaro cactus
- 12 metres – length of a whale shark, largest living fish
- 12 metres – wingspan of a Quetzalcoatlus, a pterosaur
- 12.8 metres – length of a Titanoboa, the largest snake to have ever lived
- 13 metres – length of a giant squid and colossal squid, the largest living invertebrates
- 15 metres – approximate distance the tropical circles of latitude are moving towards the equator and the polar circles are moving towards the poles each year due to a natural, gradual decrease in the Earth's axial tilt
- 16 metres – length of a sperm whale, the largest toothed whale
- 18 metres – height of a Sauroposeidon, the tallest-known dinosaur
- 20 metres – length of a Leedsichthys, the largest-known fish to have lived
- 21 metres – height of High Force waterfall in England
- 30.5 metres – length of the lion's mane jellyfish, the largest jellyfish in the world
- 33 metres – length of a blue whale,[109] the largest animal on earth, living or extinct, in terms of mass
- 39 metres – length of a Supersaurus, the longest-known dinosaur and longest vertebrate[110]
- 52 metres – height of Niagara Falls[34]
- 55 metres – length of a bootlace worm, the longest-known animal[111]
- 66 metres – highest possible sea level rise due to a complete melting of all ice on Earth
- 83 metres – height of a Western hemlock
- 84 metres – height of General Sherman, the largest tree in the world
Astronomical
- 30 metres – diameter of, a rapidly spinning meteoroid
- 30.8568 metres – 1 femtoparsec
- 32 metres – approximate diameter of 2008 HJ, a small meteoroid
1 hectometre
The (SI symbol: ) is a unit of length in the metric system equal to 100 metres (102 m). To compare different orders of magnitude this section lists lengths between 100 metres and 1,000 metres (1 kilometre).
Conversions
100 metres (sometimes termed a hectometre) is equal to:
- 328 feet
- one side of a 1 hectare square
- a fifth of a modern li, a Chinese unit of measurement
- the approximate distance travelled by light in 300 nanoseconds
Human-defined scales and structures
- 100 metres – wavelength of the highest medium wave radio frequency, 3 MHz
- 100 metres – spacing of location marker posts on British motorways
- 110 metres – height of the Saturn V
- 138.8 metres – height of the Great Pyramid of Giza (Pyramid of Cheops)
- 139 metres – height of the world's tallest roller coaster, Kingda Ka[112]
- 157 metres – height of the Cologne Cathedral
- 162 metres – height of the Ulm Minster, the tallest church building in the world
- 165 metres – height of the Dushanbe Flagpole, the tallest flagpole from May 2011 - September 2014
- 169 metres – height of the Washington Monument
- 171 metres – height of the Jeddah Flagpole, the tallest flagpole from September 2014 – December 2021
- 182 metres – height of the Statue of Unity, the world's tallest statue
- 187 metres – shortest wavelength of the broadcast radio AM band, 1600 kHz
- 192 metres – height of the Gateway Arch
- 202 metres – height of the Cairo Flagpole, the tallest flagpole as of December 2021
- 202 metres – length of the Széchenyi Chain Bridge connecting Buda and Pest
- 220 metres – height of the Hoover Dam
- 245 metres – length of the LZ 129 Hindenburg
- 270 metres – length of the Titanic
- 318 metres – height of The New York Times Building
- 318.9 metres – height of the Chrysler Building
- 328 metres – height of Auckland's Sky Tower, the tallest free-standing structure in the Southern Hemisphere (1996–2022)
- 330 metres – height of the Eiffel Tower (including antenna)[113]
- 336 metres – height of the world's tallest bridge as of October 2023, the Millau Viaduct
- 364.75 metres – length of the Icon of the Seas
- 390 metres – height of the Empire State Building
- 400–800 metres – approximate heights of the world's tallest skyscrapers from 1931 to 2010
- 458 metres – length of the Knock Nevis, the world's largest supertanker
- 553.33 metres – height of the CN Tower[114]
- 555 metres – longest wavelength of the broadcast radio AM band, 540 kHz
- 630 metres – height of the KVLY-TV mast, second-tallest structure in the world
- 646 metres – height of the Warsaw radio mast, the world's tallest structure until its collapse in 1991
- 828 metres – height of Burj Khalifa, world's tallest structure on 17 January 2009[115]
- 1,000 metres – wavelength of the lowest mediumwave radio frequency, 300 kHz
Sports
- 100 metres – the distance a very fast human can run in about 10 seconds
- 100.584 metres – length of a Canadian football field between the goal lines (110 yards)
- 91.5 metres – 137 metres – length of a soccer field
- 105 metres – length of football pitch (UEFA stadium categories 3 and 4)
- 105 metres – length of a typical football field
- 109.73 metres – total length of an American football field (120 yards, including the end zones)
- 110–150 metres – the width of an Australian football field
- 135–185 metres – the length of an Australian football field
- 137.16 metres – total length of a Canadian football field, including the end zones (150 yards)
Nature
- 115.5 metres – height of the world's tallest tree in 2007, the Hyperion sequoia[116]
- 310 metres – maximum depth of Lake Geneva
- 340 metres – distance sound travels in air at sea level in one second; see Speed of sound
- 947 metres – height of the Tugela Falls, the highest waterfall in Africa
- 979 metres – height of the Angel Falls, the world's highest free-falling waterfall (Venezuela)
Astronomical
1 kilometre
The (SI symbol: ) is a unit of length in the metric system equal to metres (103 m). To help compare different orders of magnitude, this section lists lengths between 1 kilometre and 10 kilometres (103 and 104 metres).
Conversions
1 kilometre (unit symbol km) is equal to:
Human-defined scales and structures
- 1 km – wavelength of the highest long wave radio frequency, 300 kHz[118]
- 4 km – Width of Central Park
- 1.280 km – span of the Golden Gate Bridge (distance between towers)[119]
- 1.609 km – 1 statute mile
- 1.852 km – 1 nautical mile, equal to 1 arcminute of latitude at the surface of the Earth[120]
- 1.991 km – span of the Akashi Kaikyō Bridge
- 2.309 km – axial length of the Three Gorges Dam, the largest dam in the world[35]
- 3.991 km – length of the Akashi Kaikyō Bridge, longest suspension bridge in the world
- 5.072 km – elevation of Tanggula Mountain Pass, below highest peak in the Tanggula Mountains, highest railway pass in the world
- 5.8 km – elevation of Cerro Aucanquilcha, highest road in the world, located in Chile[121]
- 98 airports have paved runways from 4 km to 5.5 km in length.
- 8 km – length of Palm Jebel Ali, an artificial island built off the coast of Dubai
- 9.8 km – length of The World, an artificial archipelago that is also built off the coast of Dubai, whose islands resemble a world map
Nature
- 1.5 km – distance sound travels in water in one second
Geographical
See also: List of highest mountains on Earth.
- 1.637 km – deepest dive of Lake Baikal in Russia, the world's largest freshwater lake[122]
- 2.228 km – height of Mount Kosciuszko, highest point on mainland Australia[123]
- Most of Manhattan is from 3 to 4 km wide.
- 3.776 km – height of Mount Fuji, highest peak in Japan
- 4.478 km – height of Matterhorn
- 4.509 km – height of Mount Wilhelm, highest peak in Papua New Guinea
- 4.810 km – height of Mont Blanc, highest peak in the Alps
- 4.884 km – height of Carstensz Pyramid, highest peak in Oceania[124]
- 4.892 km – height of Mount Vinson, highest peak in Antarctica
- 5.610 km – height of Mount Damavand, highest peak in Iran
- 5.642 km – height of Mount Elbrus, highest peak in Europe
- 5.895 km – height of Mount Kilimanjaro, highest peak in Africa
- 6.081 km – height of Mount Logan, highest peak in Canada
- 6.190 km – height of Denali, highest peak in North America
- 6.959 km – height of Aconcagua, highest peak in South America
- 7.5 km – depth of Cayman Trench, deepest point in the Caribbean Sea
- 8.611 km – height of K2, second highest mountain on Earth
- 8.848 km – height of Mount Everest, highest peak on Earth, on the border between Nepal and China
Astronomical
10 kilometres (1 myriametre)
To help compare different orders of magnitude, this section lists lengths between 10 and 100 kilometres (104 to 105 metres). The myriametre[125] (sometimes also spelled myriometre; 10,000 metres) is a deprecated unit name; the decimal metric prefix myria-[126] (sometimes also written as myrio-[127] [128] [129]) is obsolete[130] [131] and was not included among the prefixes when the International System of Units was introduced in 1960.
Conversions
10 kilometres is equal to:
Sports
Human-defined scales and structures
Geographical
Astronomical
100 kilometres
A length of 100 kilometres (about 62 miles), as a rough amount, is relatively common in measurements on Earth and for some astronomical objects.It is the altitude at which the FAI defines spaceflight to begin.
To help compare orders of magnitude, this section lists lengths between 100 and 1,000 kilometres (105 and 106 metres).
Conversions
A distance of 100 kilometres is equal to about 62 miles (or 100disp=out8disp=out).
Human-defined scales and structures
Geographical
Astronomical
1 megametre
The (SI symbol: ) is a unit of length in the metric system equal to metres (106 m). To help compare different orders of magnitude, this section lists lengths starting at 106 m (1 Mm or 1,000 km).
Conversions
1 megametre is equal to:
- 1 E+6 m (one million metres)
- approximately 621.37 miles
- 1 E+12 μm (one trillion micrometres)
- Side of square with area 1,000,000 km2
Human-defined scales and structures
- 2.100 Mm – Length of proposed Iran-Pakistan-India gas pipe
- 2.100 Mm – Distance from Casablanca to Rome
- 2.288 Mm – Length of the official Alaska Highway when it was built in the 1940s[142]
- 3.069 Mm – Length of Interstate 95 (from Houlton, Maine to Miami, Florida)
- 3.846 Mm – Length of U.S. Route 1 (from Fort Kent, Maine to Key West, Florida)
- 5.000 Mm – Width of the United States
- 5.007 Mm – Estimated length of Interstate 90 (Seattle, Washington to Boston, Massachusetts)
- 5.614 Mm – Length of the Australian Dingo Fence[143]
- 6.371 Mm – Global-average Earth radius
- 6.4 Mm – Length of the Great Wall of China
- 7.821 Mm – Length of the Trans-Canada Highway, the world's longest national highway (from Victoria, British Columbia to St. John's, Newfoundland)
- 8.836 Mm – Road distance between Prudhoe Bay, Alaska, and Key West, Florida, the endpoints of the U.S. road network
- 8.852 Mm – Aggregate length of the Great Wall of China, including trenches, hills and rivers[144]
- 9.259 Mm – Length of the Trans-Siberian railway[145]
Sports
- The Munda Biddi Trail in WA, Australia is over 1,000 km long – the world's longest off-road cycle trail
- 1.200 Mm – the length of the Paris–Brest–Paris bicycling event
- Several endurance auto races are, or were, run for 1,000 km:
Geographical
Astronomical
10 megametres
To help compare different orders of magnitude, this section lists lengths starting at 107 metres (10 megametres or 10,000 kilometres).
Conversions
10 megametres (10 Mm) is
Human-defined scales and structures
Geographical
Astronomical
- 12.000 Mm – Diameter of Sirius B, a white dwarf[147]
- 12.104 Mm – Diameter of Venus
- 12.742 Mm – Diameter of Earth
- 12.900 Mm – Minimum distance of the meteoroid from the centre of Earth on 31 March 2004, closest on record
- 14.000 Mm – Smallest diameter of Jupiter's Great Red Spot
- 19.000 Mm – Separation between Pluto and Charon
- 30.8568 Mm – 1 nanoparsec
- 34.770 Mm – Minimum distance of the asteroid 99942 Apophis on 13 April 2029 from the centre of Earth
- 35.786 Mm – Altitude of geostationary orbit
- 40.005 Mm – Polar circumference of the Earth
- 40.077 Mm – Equatorial circumference of the Earth
- 49.528 Mm – Diameter of Neptune
- 51.118 Mm – Diameter of Uranus
100 megametres
To help compare different orders of magnitude, this section lists lengths starting at 108 metres (100 megametres or 100,000 kilometres or 62,150 miles).
1 gigametre
- lower part: their darker mirror images
(artist's interpretation).The (SI symbol: ) is a unit of length in the metric system equal to metres (109 m). To help compare different distances this section lists lengths starting at 109 metres (1 gigametre (Gm) or 1 billion metres).
10 gigametres
To help compare different distances this section lists lengths starting at 1010 metres (10 gigametres (Gm) or 10 million kilometres, or 0.07 astronomical units).
100 gigametres
To help compare distances at different orders of magnitude this section lists lengths starting at 1011 metres (100 gigametre or 100 million kilometres or 0.7 astronomical units).
1 terametre
The (SI symbol: ) is a unit of length in the metric system equal to metres (1012 m). To help compare different distances, this section lists lengths starting at 1012 m (1 Tm or 1 billion km or 6.7 astronomical units).
10 terametres
To help compare different distances this section lists lengths starting at 1013 m (10 Tm or 10 billion km or 67 astronomical units).
- 10 Tm – 67 AU – Diameter of a hypothetical quasi-star
- 11.1 Tm – 74.2 AU – Distance that Voyager 1 began detecting returning particles from termination shock
- 11.4 Tm – 76.2 AU – Perihelion distance of 90377 Sedna
- 12.1 Tm – 70 to 90 AU – Distance to termination shock (Voyager 1 crossed at 94 AU)
- 12.9 Tm – 86.3 AU – Distance to 90377 Sedna in March 2014
- 13.2 Tm – 88.6 AU – Distance to Pioneer 11 in March 2014
- 14.1 Tm – 94.3 AU – Estimated radius of the Solar System
- 14.4 Tm – 96.4 AU – Distance to Eris in March 2014 (now near its aphelion)
- 15.1 Tm – 101 AU – Distance to heliosheath
- 16.5 Tm – 111 AU – Distance to Pioneer 10 as of March 2014
- 16.6 Tm – 111.2 AU – Distance to Voyager 2 as of May 2016
- 18 Tm – 123.5 AU – Distance between the Sun to the farthest dwarf planet in the Solar System, the Farout 2018 VG18
- 20.0 Tm – 135 AU – Distance to Voyager 1 as of May 2016
- 20.6 Tm – 138 AU – Distance to Voyager 1 as of late February 2017
- 21.1 Tm – 141 AU – Distance to Voyager 1 as of November 2017
- 25.9 Tm – 173 AU – One light-day
- 30.8568 Tm – 206.3 AU – 1 milliparsec
- 55.7 Tm – 371 AU – Aphelion distance of the comet Hale-Bopp
100 terametres
To help compare different distances this section lists lengths starting at 1014 m (100 Tm or 100 billion km or 670 astronomical units).
1 petametre
The (SI symbol: ) is a unit of length in the metric system equal to 1015 metres. To help compare different distances this section lists lengths starting at 1015 m (1 Pm or 1 trillion km or 6685 astronomical units (AU) or 0.11 light-years).
- 1.0 Pm = 0.105702341 light-years
- 1.9 Pm ± 0.5 Pm = 12,000 AU = 0.2 light-year radius of Cat's Eye Nebula's inner core[174]
- 3.08568 Pm = 20,626 AU = 1 deciparsec
- 4.7 Pm = 30,000 AU = half-light-year diameter of Bok globule Barnard 68[175]
- 7.5 Pm – 50,000 AU – Possible outer boundary of Oort cloud (other estimates are 75,000 to 125,000 or even 189,000 AU (1.18, 2, and 3 light-years, respectively))
- 9.5 Pm – 63,241.1 AU – One light-year, the distance traveled by light in one year
- 9.9 Pm – 66,000 AU – Aphelion distance of the C/1999 F1 (Catalina)
10 petametres
To help compare different distances this section lists lengths starting at 1016 m (10 Pm or 66,800 AU, 1.06 light-years).
- 15 Pm – 1.59 light-years – Possible outer radius of Oort cloud
- 20 Pm – 2.11 light-years – maximum extent of influence of the Sun's gravitational field
- 30.9 Pm – 3.26 light-years – 1 parsec
- 39.9 Pm – 4.22 light-years – Distance to Proxima Centauri (nearest star to Sun)
- 81.3 Pm – 8.59 light-years – Distance to Sirius
- 94.6 Pm – 1 light-decade
100 petametres
To help compare different distances this section lists lengths between 1017 m (100 Pm or 11 light-years) and 1018 m (106 light-years).
- 110 Pm – 12 light-years – Distance to Tau Ceti
- 230 Pm – 24 light-years – Diameter of the Orion Nebula[176] [177]
- 240 Pm – 25 light-years – Distance to Vega
- 260 Pm – 27 light-years – Distance to Chara, a star approximately as bright as the Sun. Its faintness gives an idea how the Sun would appear when viewed from this distance.
- 308.568 Tm – 32.6 light-years – 1 dekaparsec
- 350 Pm – 37 light-years – Distance to Arcturus
- 373.1 Pm – 39.44 light-years – Distance to TRAPPIST-1, a star recently discovered to have 7 planets around it
- 400 Pm – 42 light-years – Distance to Capella
- 620 Pm – 65 light-years – Distance to Aldebaran
- 750 Pm – 79.36 light-years – Distance to Regulus
- 900 Pm – 92.73 light-years – Distance to Algol
- 946 Pm – 1 light-century
1 exametre
The (SI symbol: ) is a unit of length in the metric system equal to 1018 metres. To help compare different distances this section lists lengths between 1018 m (1 Em or 105.7 light-years) and 1019 m (10 Em or 1,057 light-years).
10 exametres
To help compare different orders of magnitude, this section lists distances starting at 10 Em (1019 m or 1,100 light-years).
- 10.6 Em – 1,120 light-years – Distance to WASP-96b
- 13 Em – 1,300 light-years – Distance to the Orion Nebula[183]
- 14 Em – 1,500 light-years – Approximate thickness of the plane of the Milky Way galaxy at the Sun's location
- 14.2 Em – 1,520 light-years – Diameter of the NGC 604
- 30.8568 Em – 3,261.6 light-years – 1 kiloparsec
- 31 Em – 3,200 light-years – Distance to Deneb according to Hipparcos
- 46 Em – 4,900 light-years – Distance to OGLE-TR-56, the first extrasolar planet discovered using the transit method
- 47 Em – 5,000 light-years – Distance to the Boomerang nebula, coldest place known (1 K)
- 53 Em – 5,600 light-years – Distance to the globular cluster M4 and the extrasolar planet PSR B1620-26 b within it
- 61 Em – 6,500 light-years – Distance to Perseus Spiral Arm (next spiral arm out in the Milky Way galaxy)
- 71 Em – 7,500 light-years – Distance to Eta Carinae
- 94.6073 Em – 1 light-decamillennium = 10,000 light-years
100 exametres
To help compare different orders of magnitude, this section lists distances starting at 100 Em (1020 m or 11,000 light-years).
1 zettametre
The (SI symbol: ) is a unit of length in the metric system equal to 1021 metres.[184] To help compare different orders of magnitude, this section lists distances starting at 1 Zm (1021 m or 110,000 light-years).
10 zettametres
To help compare different orders of magnitude, this section lists distances starting at 10 Zm (1022 m or 1.1 million light-years).
100 zettametres
To help compare different orders of magnitude, this section lists distances starting at 100 Zm (1023 m or 11 million light-years).
1 yottametre
The (SI symbol: ) is a unit of length in the metric system equal to 1024 metres.[184]
To help compare different orders of magnitude, this section lists distances starting at 1 Ym (1024 m or 105.702 million light-years).
10 yottametres
To help compare different orders of magnitude, this section lists distances starting at 10 Ym (1025 m or 1.1 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depends on the cosmological models used.
100 yottametres
To help compare different orders of magnitude, this section lists distances starting at 100 Ym (1026 m or 11 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depend on the cosmological models used.
- 124 Ym – redshift 7.54 – 13.1 billion light-years – Light travel distance (LTD) to the quasar ULAS J1342+0928, the most distant-known quasar as of 2017
- 130 Ym – redshift 1,000 – 13.8 billion light-years – Distance (LTD) to the source of the cosmic microwave background radiation; radius of the observable universe measured as a LTD
- 260 Ym – 27.4 billion light-years – Diameter of the observable universe (double LTD)
- 440 Ym – 46 billion light-years – Radius of the universe measured as a comoving distance
- 590 Ym – 62 billion light-years – Cosmological event horizon: the largest comoving distance from which light will ever reach us (the observer) at any time in the future
- 886.48 Ym – 93.7 billion light-years – The diameter of the observable universe (twice the particle horizon); however, there might be unobserved distances that are even greater.
1 ronnametre
The (SI symbol: ) is a unit of length in the metric system equal to 1027 metres.[184]
To help compare different orders of magnitude, this section lists distances starting at 1 Rm (1027 m or 110 billion light-years). At this scale, expansion of the universe becomes significant. Distance of these objects are derived from their measured redshifts, which depend on the cosmological models used.
See also
External links
Notes and References
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