# Orders of magnitude (length)

(Redirected from 1 E3 m)

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 P Fixed value (not a range). Quantum foam, string
10−18 10−15 am proton, neutron, pion
Atomic to cellular 10−15 10−12 fm Atomic nucleus
10−12 10−9 pm Wavelength of gamma rays and X-rays, hydrogen atom
10−9 10−6 nm DNA helix, virus, wavelength of optical spectrum, transistors used in CPUs
Cellular to human 10−6 10−3 μm Bacterium, fog water droplet, human hair's diameter[note 1]
10−3 1 mm Mosquito, golf ball, domestic cat, violin, football
Human to astronomical 1 103 m Piano, human, automobile, sperm whale, football field, Eiffel Tower
103 106 km Mount Everest, length of Panama Canal and Trans-Siberian Railway, larger asteroid
Astronomical 106 109 Mm The Moon, Earth, one light-second
109 1012 Gm Sun, one light-minute, Earth's orbit
1012 1015 Tm Orbits of outer planets, Solar System
1015 1018 Pm A light-year, the distance to Proxima Centauri
1018 1021 Em Galactic arm
1021 1024 Zm Milky Way, distance to Andromeda Galaxy
1024 1027 Ym 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 ${\displaystyle 1.6\times 10^{-35}}$ metres and ${\displaystyle 10^{10^{10^{122}}}}$metres.

### Subatomic scale

Factor (m) Multiple Value Item
0 0 0 Singularity
10−35 1 Planck length 0.0000162 qm  Planck length; typical scale of hypothetical loop quantum gravity or size of a hypothetical string and of branes; according to string theory, lengths smaller than this do not make any physical sense.[1] Quantum foam is thought to exist at this scale.
10−24 1 yoctometre (ym) 142 ym Effective cross section radius of 1 MeV neutrinos[2]
10−21 1 zeptometre (zm) Preons, hypothetical particles proposed as subcomponents of quarks and leptons; the upper bound for the width of a cosmic string in string theory
7 zm Effective cross section radius of high-energy neutrinos[3]
310 zm De Broglie wavelength of protons at the Large Hadron Collider (4 TeV as of 2012)
10−18 1 attometre (am) Upper limit for the size of quarks and electrons
Sensitivity of the LIGO detector for gravitational waves[4]
Upper bound of the typical size range for "fundamental strings"[1]
10−17 10 am Range of the weak force
10−16 100 am 850 am Approximate proton radius[5]

### Atomic to cellular scale

Factor (m) Multiple Value Item
10−15 1 femtometre (fm, fermi) 1 fm Approximate limit of the gluon-mediated color force between quarks[6][7]
1.5 fm Effective cross section radius of an 11 MeV proton[8]
3 fm Approximate limit of the meson-mediated nuclear binding force[6][7]
1.75 to 15 fm Diameter range of the atomic nucleus[1][10]
10−12 1 picometre (pm) 0.75 to 0.8225 pm Longest wavelength of gamma rays
1 pm Distance between atomic nuclei in a white dwarf
2.4 pm Compton wavelength of electron
5 pm Wavelength of shortest X-rays
10−11 10 pm
28 pm Radius of helium atom
10−10 100 pm 100 pm 1 ångström (also covalent radius of sulfur atom[11])
154 pm Length of a typical covalent bond (C–C)
280 pm Average size of the water molecule (actual lengths may vary)
500 pm Width of protein α helix
10−9 1 nanometre (nm) 1 nm Diameter of a carbon nanotube[12] Diameter of smallest transistor gate (as of 2016)[13]
2 nm Diameter of the DNA helix[14]
2.5 nm Smallest microprocessor transistor gate oxide thickness (as of January 2007)[citation needed]
3.4 nm Length of a DNA turn (10 bp)[15]
6–10 nm Thickness of cell membrane
10−8 10 nm 10 nm Thickness of cell wall in Gram-negative bacteria[citation needed]
10 nm As of 2016, the 10 nanometre was the smallest semiconductor device fabrication node[16]
40 nm Extreme ultraviolet wavelength
50 nm Flying height of the head of a hard disk[17]
10−7 100 nm 121.6 nm Wavelength of the Lyman-alpha line[18]
120 nm Typical diameter of the human immunodeficiency virus (HIV)[19]
400–700 nm Approximate wavelength range of visible light[20]

### 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[21]
4 μm Typical diameter of spider silk[22]
7 μm Typical size of a red blood cell[23]
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[24]
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[25]
750 μm Maximum diameter of Thiomargarita namibiensis, the largest bacterium ever discovered (as of 2010)
10−3 1 millimetre (mm) ~5 mm Length of an average flea is 1–10 mm (usually <5 mm)[26]
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[27]
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[28]
900 mm Average length of a rapier, a fencing sword[29]

### 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.[30]
8.38 m Length of a London bus (AEC Routemaster)
101 1 decametre (dam) 33 m Length of the longest-known blue whale[31]
52 m Height of the Niagara Falls[32]
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[33][34]
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 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, as of May 2010 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.[35]
106 1 megametre (Mm) 2.38 Mm Diameter of dwarf planet Pluto, formerly the smallest planet category[note 2] 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
6.371 Mm Average radius of Earth
6.378 Mm Equatorial radius of Earth
6.4 Mm Length of the Great Wall of China
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)[36]
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)[37]
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[1]
21.49 Tm Distance of the Voyager 1 spacecraft from Sun (as of Oct 2018), the farthest man-made object so far[38]
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[39]
200 Tm Total length of DNA molecules in all cells of an adult human body[citation needed]
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[40]
1019 10 Em 9.46 Em Average thickness of Milky Way Galaxy[41] (1,000 to 3,000 ly by 21 cm observations[42])
1020 100 Em 113.5 Em Thickness of Milky Way Galaxy's gaseous disk[43]
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[44][45][46][47]
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[48]
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)[49]
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[1]
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[50] It equivalently implies that there are at minimum 21 particle horizon-sized volumes in the universe.
${\displaystyle 10^{10^{115}}}$[note 3] ${\displaystyle 10^{10^{115}}}$ m ${\displaystyle 10^{10^{115}}}$ 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.[51][52]
${\displaystyle 10^{10^{10^{122}}}}$ ${\displaystyle 10^{10^{10^{122}}}}$ m ${\displaystyle 10^{10^{10^{122}}}}$ m Minimal size of universe after cosmological inflation, implied by one resolution of the No-Boundary Proposal[53]

## 1 quectometre and less

The quectometre (SI symbol: qm) is a unit of length in the metric system equal to 10−30 metres. 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.[54]

## 1 rontometre

The rontometre (SI symbol: rm) is a unit of length in the metric system equal to 10−27 metres.

• 1 rm – 1 rontometre, a subdivision of the metre in the SI base unit of length, one octillionth of a metre.[54]

## 1 yoctometre

The yoctometre (SI symbol: ym) is a unit of length in the metric system equal to 10−24 metres.

## 1 zeptometre

The zeptometre (SI symbol: zm) is a unit of length in the metric system equal to 10−21 metres. To help compare different orders of magnitude, this section lists lengths between 10−21 m and 10−20 m (1 zm and 10 zm).

## 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 attometre (SI symbol: am) is a unit of length in the metric system equal to 10−18 metres. 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).

## 1 femtometre (or 1 fermi)

The (SI symbol: fm) is a unit of length in the metric system equal to 10−15 metres. In particle physics, this unit is sometimes called a fermi, 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 10−12 metres (1/1000000000000 m = 0.000000000001 m). 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).

• 25 pm – approximate radius of a helium atom, the smallest neutral atom
• 30.8568 pm – 1 rontoparsec
• 50 pm – radius of a hydrogen atom
• 50 pm – bohr radius: approximate radius of a hydrogen atom
• ~50 pm – best resolution of a high-resolution transmission electron microscope
• 60 pm – radius of a carbon atom
• 93 pm – length of a diatomic carbon molecule
• 96 pm – H–O bond length in a water molecule

## 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: nm) is a unit of length in the metric system equal to 10−9 metres (1/1000000000 m = 0.000000001 m). 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[65]
• 100 nm – 90% of particles in wood smoke are smaller than this.[citation needed]
• 120 nm – greatest particle size that can fit through a ULPA filter[citation needed]
• 120 nm – diameter of a human immunodeficiency virus (HIV)[66]
• 120 nm – approximate diameter of SARS-CoV-2[67]
• 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
• 300–400 nm – near ultraviolet wavelength
• 300 nm – greatest particle size that can fit through a HEPA (high efficiency particulate air) filter (N100 removes up to 99.97% at 0.3 micrometres, N95 removes up to 95% at 0.3 micrometres)[citation needed]
• 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: μm) is a unit of length in the metric system equal to 10−6 metres (1/1000000 m = 0.000001 m). 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)[79] is deprecated; the decimal metric prefix myrio-[80] is obsolete[81][82][83] and was not included among the prefixes when the International System of Units was introduced in 1960.

## 1 millimetre

The (SI symbol: mm) is a unit of length in the metric system equal to 10−3 metres (1/1000 m = 0.001 m). 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[26]
• 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[88]
• 7.1 mm – length of a sunflower seed
• 7.62×51mm NATO – common military ammunition size[89]
• 8 mm – width of old-format home movie film
• 8 mm – length of a Paedocypris progenetica, the smallest-known fish[90]

## 1 centimetre

The (SI symbol: cm) is a unit of length in the metric system equal to 10−2 metres (1/100 m = 0.01 m). 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[91]
• 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[92]
• 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[93]
• 4.3 cm – minimum diameter of a golf ball[94]
• 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[27]
• 8.6 cm × 5.4 cm – dimensions of a standard credit card[citation needed]
• 9 cm – length of a speckled padloper, the smallest-known turtle

## 1 decimetre

The (SI symbol: dm) is a unit of length in the metric system equal to 10−1 metres (1/10 m = 0.1 m). 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:

### 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[29]
• 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
• 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[95])

### 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 1299,792,458, or 3.3356409519815E-9 of a second.

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
• 1.435 m – standard gauge of railway track used by about 60% of railways in the world = 4 ft 812 in
• 2.5 m – distance from the floor to the ceiling in an average residential house[96]
• 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
• 8.38 m – the length of a London Bus (AEC Routemaster)

### Sports

• 2.44 m – height of an association football goal[97]
• 2.45 m – highest high jump by a human (Javier Sotomayor)[98]
• 3.05 m – (10 feet) height of the basket in basketball
• 8.95 m – longest long jump by a human (Mike Powell)[99]

### Nature

• 1 m – height of Homo floresiensis (the "Hobbit")
• 1.15 m – a pizote (mammal)
• 1.63 m – (5 feet 4 inches) (or 64 inches) – height of average U.S. female human as of 2002 (source: U.S. Centers for Disease Control and Prevention (CDC))
• 1.75 m – (5 feet 8 inches) – height of average U.S. male human as of 2002 (source: U.S. CDC as per female above)
• 2.5 m – height of a sunflower
• 2.72 m – (8 feet 11 inches) – tallest-known human (Robert Wadlow)[30]
• 3.63 m – the record wingspan for living birds (a wandering albatross)
• 5 m – length of an elephant
• 5.2 m – height of a giraffe[100]
• 5.5 m – height of a Baluchitherium, the largest land mammal ever lived
• 6.5 m – wingspan of Argentavis, the largest flying bird known
• 7.4 m – wingspan of Pelagornis, the bird with longest wingspan ever.[101]
• 7.5 m – approximate length of the human gastrointestinal tract

### Astronomical

• 3–6 m – approximate diameter of 2003 SQ222, a meteoroid
• 4.1 m – diameter of 2008 TC3, a small asteroid that flew into the Earth's atmosphere on 7 October 2008[102]

## 1 decametre

The (SI symbol: dam) 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:

### 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)[103]
• 20 metres – length of cricket pitch (22 yards)[104]
• 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 (5313 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[citation needed]
• 12 metres – length of a whale shark, largest living fish
• 12 metres – wingspan of a Quetzalcoatlus, a pterosaur
• 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
• 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
• 33 metres – length of a blue whale,[105] 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[106]
• 52 metres – height of Niagara Falls[32]
• 55 metres – length of a bootlace worm, the longest-known animal[107]
• 66 metres - highest possible sea level rise due to a complete melting of all ice on Earth
• 83 metres – height of a Western hemlock

### Astronomical

• 30 metres – diameter of 1998 KY26, a rapidly spinning meteoroid
• 30.8568 metres – 1 femtoparsec
• 32 metres – approximate diameter of 2008 HJ, a small meteoroid

## 1 hectometre

The (SI symbol: hm) 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
• 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[109]
• 169 metres - height of the Washington Monument
• 187 metres – shortest wavelength of the broadcast radio AM band, 1600 kHz
• 192 metres - height of the Gateway Arch
• 202 metres – length of the Széchenyi Chain Bridge connecting Buda and Pest
• 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[when?]
• 330 metres – height of the Eiffel Tower (including antenna)[110]
• 341 metres – height of the world's tallest bridge, the Millau Viaduct[when?]
• 390 metres – height of the Empire State Building
• 400–800 metres – heights of the world's tallest skyscrapers of the past 80 years[when?]
• 458 metres – length of the Knock Nevis, the world's largest supertanker
• 553.33 metres – height of the CN Tower[111]
• 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[112]
• 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[97]
• 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[113]
• 310 metres – maximum depth of Lake Geneva
• 340 metres – distance sound travels in air at sea level in one second; see Speed of sound
• 979 metres – height of the Salto Angel, the world's highest free-falling waterfall (Venezuela)
• 1500 metres – distance sound travels in water in one second

## 1 kilometre

The (SI symbol: km) is a unit of length in the metric system equal to 1000 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:

## 10 kilometres

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-[80] (sometimes also written as myrio-[126][127][128]) is obsolete[81][82][83] and was not included among the prefixes when the International System of Units was introduced in 1960.

### Conversions

10 kilometres is equal to:

## 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 62.13711922 miles).

## 1 megametre

The megametre (SI symbol: Mm) is a unit of length in the metric system equal to 1000000 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

## 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

### Astronomical

• 12.000 Mm – Diameter of Sirius B, a white dwarf[144]
• 12.104 Mm – Diameter of Venus
• 12.742 Mm – Diameter of Earth
• 12.900 Mm – Minimum distance of the meteoroid 2004 FU162 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 gigametre (SI symbol: Gm) is a unit of length in the metric system equal to 1000000000 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).

• 109 Gm (0.7 au) Distance between Venus and the Sun
• 149.6 Gm (93.0 million mi; 1.0 au) – Distance between the Earth and the Sun – the original definition of the astronomical unit
• 180 Gm (1.2 au) – Maximum diameter of Sagittarius A*, the supermassive black hole in the center of Milky Way galaxy
• 228 Gm (1.5 au) – Distance between Mars and the Sun
• ≈280 Gm (1.9 au) – Diameter of Deneb, a blue supergiant and the brightest star in the Cygnus[155]
• 570 Gm (3.8 au) – Length of the tail of Comet Hyakutake measured by Ulysses; the actual value could be much higher
• ≈590 Gm (3.9 au) – Diameter of the Pistol Star, a blue hypergiant star[156]
• 591 Gm (4.0 au) – Minimum distance between the Earth and Jupiter
• 780 Gm (5.2 au) – Distance between Jupiter and the Sun
• 947 Gm (6.4 au) – Diameter of Antares A
• 965 Gm (6.4 au) – Maximum distance between the Earth and Jupiter

## 1 terametre

The terametre (SI symbol: Tm) is a unit of length in the metric system equal to 1000000000000 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
• 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 petametre (SI symbol: Pm) 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[167][168]
• 3.08568 Pm = 20,626 AU = 1 deciparsec
• 4.7 Pm = 30,000 AU = half-light-year diameter of Bok globule Barnard 68[169]
• 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).

## 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[170][171]
• 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

## 1 exametre

The exametre (SI symbol: Em) 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).

## 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 zettametre (SI symbol: Zm) is a unit of length in the metric system equal to 1021 metres.[54] 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 yottametre (SI symbol: Ym) is a unit of length in the metric system equal to 1024 metres.[54]

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.

## 1 ronnametre

The ronnametre (SI symbol: Rm) is a unit of length in the metric system equal to 1027 metres.[54]

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.

## Notes

1. ^ The diameter of human hair ranges from 17 to 181 μm Ley, Brian (1999). Elert, Glenn (ed.). "Diameter of a human hair". The Physics Factbook. Retrieved 8 December 2018.
2. ^ a b The exact category (asteroid, dwarf planet, or planet) to which particular Solar System objects belong, has been subject to some revision since the discovery of extrasolar planets and trans-Neptunian objects
3. ^ 10115 is 1 followed by 115 zeroes, or a googol multiplied by a quadrillion. 1010115 is 1 followed by a quadrillion googol zeroes. 101010122is 1 followed by 1010122 (a googolplex10 sextillion) zeroes.
4. ^ But not cloud or high-level fog droplets; droplet size increases with altitude. For a contradictory study indicating larger drop sizes even in ground fog, see Eldridge, Ralph G. (October 1961). "A Few Fog Drop-Size Distributions". Journal of Meteorology. 18 (5): 671–6. Bibcode:1961JAtS...18..671E. doi:10.1175/1520-0469(1961)018<0671:AFFDSD>2.0.CO;2.

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