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Orders of magnitude (length)

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Objects of sizes in different order of magnitude (at inconsistent intervals)
Graphical overview of sizes

The following are examples of orders of magnitude for different lengths.

Overview

[edit]
Scale Range (m) Unit Example items
≥ <
Subatomic – 0 – Gravitational singularity
10−36 10−33 ℓP 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

[edit]

To help compare different orders of magnitude, the following list describes various lengths between  metres and metres.

Subatomic scale

[edit]
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

[edit]
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]
2.81794 fm Classical electron radius[9]
3 fm Approximate limit of the meson-mediated nuclear binding force[6][7]
750 to 822.25 fm Longest wavelength of gamma rays
10−12 1 picometre (pm) 1.75 to 15 fm Diameter range of the atomic nucleus[1][10]
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
53 pm Bohr radius (radius of a hydrogen 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 Îą 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 Upper range of thickness of cell wall in Gram-negative bacteria[16]
10 nm As of 2016, the 10 nanometre was the smallest semiconductor device fabrication node[17]
40 nm Extreme ultraviolet wavelength
50 nm Flying height of the head of a hard disk[18]
10−7 100 nm 121.6 nm Wavelength of the Lyman-alpha line[19]
120 nm Typical diameter of the human immunodeficiency virus (HIV)[20]
400–700 nm Approximate wavelength range of visible light[21]

Cellular to human scale

[edit]
Factor (m) Multiple Value Item
10−6 1 micrometre (μm)

(also called 1 micron)

1–4 Îźm Typical length of a bacterium[22]
4 Îźm Typical diameter of spider silk[23]
7 Îźm Typical size of a red blood cell[24]
10−5 10 Îźm 10 Îźm Typical size of a fog, mist, or cloud water droplet
10 Îźm Width of transistors in the Intel 4004, the world's first commercial microprocessor
12 Îźm Width of acrylic fiber
17-181 Îźm Width range of human hair[25]
10−4 100 Îźm 340 Îźm Size of a pixel on a 17-inch monitor with a resolution of 1024×768
560 Îźm Thickness of the central area of a human cornea[26]
750 Îźm Maximum diameter of Thiomargarita namibiensis, the second largest bacterium ever discovered
10−3 1 millimetre (mm) ~5 mm Length of an average flea is 1–10 mm (usually <5 mm)[27]
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[28]
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[29]
900 mm Average length of a rapier, a fencing sword[30]

Human to astronomical scale

[edit]
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.[31]
8.38 m Length of a London bus (AEC Routemaster)
101 1 decametre (dam) 33 m Length of the longest-known blue whale[32]
52 m Height of the Niagara Falls[33]
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[34][35]
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.[36]
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
6.259 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

[edit]
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)[37]
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)[38]
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]
16.09 Tm Total length of DNA molecules in all cells of an adult human body[39]
21.49 Tm Distance of the Voyager 1 spacecraft from Sun (as of Oct 2018), the farthest man-made object so far[40]
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[41]
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[42]
1019 10 Em 9.46 Em Average thickness of Milky Way Galaxy[43] (1,000 to 3,000 ly by 21 cm observations[44])
1020 100 Em 113.5 Em Thickness of Milky Way Galaxy's gaseous disk[45]
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[46][47][48][49]
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[50]
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)[51]
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[52] It equivalently implies that there are at minimum 21 particle horizon-sized volumes in the universe.
[note 3] 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.[53][54]
m m Minimal size of universe after cosmological inflation, implied by one resolution of the No-Boundary Proposal[55]

1 quectometre and less

[edit]

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.[56]

1 rontometre

[edit]

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.[56]

10 rontometres

[edit]

1 yoctometre

[edit]

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

1 zeptometre

[edit]

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

[edit]

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

[edit]

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

[edit]

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

[edit]

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

[edit]

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[59]

1 femtometre (or 1 fermi)

[edit]

The femtometre (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

[edit]

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

[edit]

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

[edit]

The picometre (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

[edit]

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

[edit]

To help compare different orders of magnitude this section lists lengths between 10−10 and 10−9 m (100 pm and 1 nm; 1 Ă… and 10 Ă…).

1 nanometre

[edit]

The nanometre (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

[edit]

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

[edit]
Comparison of sizes of semiconductor manufacturing process nodes with some microscopic objects and visible light wavelengths. At this scale, the width of a human hair is about 10 times that of the image.[68]

To help compare different orders of magnitude, this section lists lengths between 10−7 and 10−6 m (100 nm and 1 Îźm).

  • 100 nm – greatest particle size that can fit through a surgical mask[69]
  • 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[70]
  • 120 nm – diameter of a human immunodeficiency virus (HIV)[71]
  • 120 nm – approximate diameter of SARS-CoV-2[72]
  • 125 nm – standard depth of pits on compact discs (width: 500 nm, length: 850 nm to 3.5 Îźm)
  • 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)[73]
  • 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 Îźm – wavelength of near-infrared radiation

1 micrometre (or 1 micron)

[edit]
The silk for a spider's web is 5–7 Îźm (0.00020–0.00028 in) wide.

The micrometre (SI symbol: Îźm) 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 Îźm).

10 micrometres

[edit]
Fog particles are around 10–50 Îźm (0.00039–0.00197 in) long.

To help compare different orders of magnitude, this section lists lengths between 10−5 m and 10−4 m (10 Îźm and 100 Îźm).

100 micrometres

[edit]
A paramecium is around 300 Îźm (0.012 in) long.

To help compare different orders of magnitude, this section lists lengths between 10−4 m and 10−3 m (100 Îźm and 1 mm). The term myriometre (abbr. mom, equivalent to 100 micrometres; frequently confused with the myriametre, 10 kilometres)[86] is deprecated; the decimal metric prefix myrio-[87] is obsolete[88][89][90] and was not included among the prefixes when the International System of Units was introduced in 1960.

  • 100 Îźm – 1/10 of a millimetre
  • 100 Îźm – 0.00394 inches
  • 100 Îźm – smallest distance that can be seen with the naked eye
  • 100 Îźm – average diameter of a strand of human hair[25]
  • 100 Îźm – thickness of a coat of paint
  • 100 Îźm – length of a dust particle
  • 120 Îźm – the geometric mean of the Planck length and the diameter of the observable universe: 8.8 × 1026 m × 1.6 × 10−35 m
  • 120 Îźm – diameter of a human ovum
  • 170 Îźm – length of the largest sperm cell in nature, belonging to the Drosophila bifurca fruit fly[91][92]
  • 181 Îźm – maximum width of a strand of human hair[25]
  • 100–400 Îźm – length of Demodex mites living in human hair follicles
  • 175–200 Îźm – typical thickness of a solar cell.
  • 200 Îźm – typical length of Paramecium caudatum, a ciliate protist
  • 200 Îźm – nominal width of the smallest commonly available mechanical pencil lead (0.2 mm)
  • 250–300 Îźm – length of a dust mite[93]
  • 340 Îźm – length of a pixel on a 17-inch monitor with a resolution of 1024×768
  • 500 Îźm – typical length of Amoeba proteus, an amoeboid protist
  • 500 Îźm – MEMS micro-engine[94]
  • 500 Îźm – average length of a grain of sand
  • 500 Îźm – average length of a grain of salt
  • 500 Îźm – average length of a grain of sugar
  • 560 Îźm – thickness of the central area of a human cornea[26]
  • 750 Îźm – diameter of a Thiomargarita namibiensis, the largest bacteria known[95]
  • 760 Îźm – thickness of an identification card

1 millimetre

[edit]
An average red ant is about 5 mm (0.20 in) long.

The millimetre (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[27]
  • 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[96]
  • 7.1 mm – length of a sunflower seed
  • 7.62×51mm NATO – common military ammunition size[97]
  • 8 mm – width of old-format home movie film
  • 8 mm – length of a Paedocypris progenetica, the smallest-known fish[98]

1 centimetre

[edit]
An average human fingernail is 1 cm (0.39 in) wide

The centimetre (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[99]
  • 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[100]
  • 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[101]
  • 4.3 cm – minimum diameter of a golf ball[102]
  • 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[28]
  • 8.6 cm × 5.4 cm – dimensions of a standard credit card (also called CR80)[103]
  • 9 cm – length of a speckled padloper, the smallest-known turtle

1 decimetre

[edit]
An adult human foot is about 28 cm (11 in) long.

The decimetre (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

[edit]

10 centimetres (abbreviated to 10 cm) is equal to:

Wavelengths

[edit]

Human-defined scales and structures

[edit]
  • 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[30]
  • 91.44 cm = 9.144 dm – one yard (measure)

Nature

[edit]
  • 10 cm = 1 dm – diameter of the human cervix upon entering the second stage of labour
  • 11 cm = 1.1 dm – length 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[104])

Astronomical

[edit]
  • 84 cm = 8.4 dm – approximate diameter of 2008 TS26, a meteoroid

1 metre

[edit]
Leonardo da Vinci drew the Vitruvian Man within a square of side 1.83 m (6 ft 0 in) and a circle about 1.2 m (3 ft 11 in) in radius.

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.

Conversions

[edit]

1 metre is:

Human-defined scales and structures

[edit]
  • 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 812 in
  • 2.5 m – distance from the floor to the ceiling in an average residential house[105]
  • 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

[edit]
  • 2.44 m – height of an association football goal[106]
  • 2.45 m – highest high jump by a human (Javier Sotomayor)[107]
  • 3.05 m – (10 feet) height of the basket in basketball
  • 8.95 m – longest long jump by a human (Mike Powell)[108]

Nature

[edit]
  • 1 m – length of Rafflesia arnoldii, the largest flower in the world
  • 1 m – height of Homo floresiensis (the "Hobbit")
  • 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 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)
  • 2.4 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)[31]
  • 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[109]
  • 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.[110]
  • 7.5 m – approximate length of the human gastrointestinal tract

Astronomical

[edit]
  • 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[111]

1 decametre

[edit]
A blue whale has been measured as 33 m (108 ft) long; this drawing compares its length to that of a human diver and a dolphin.

The decametre (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

[edit]

10 metres (very rarely termed a decametre which is abbreviated as dam) is equal to:

Human-defined scales and structures

[edit]

Sports

[edit]
  • 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)[112]
  • 20 metres – length of cricket pitch (22 yards)[113]
  • 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

[edit]
  • 10 metres – average length of human digestive tract[citation needed]
  • 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,[114] 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[115]
  • 52 metres – height of Niagara Falls[33]
  • 55 metres – length of a bootlace worm, the longest-known animal[116]
  • 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

[edit]
  • 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

[edit]
The Great Pyramid of Giza is 138.8 m (455 ft) high.
British driver location sign and location marker post on the M27 in Hampshire. The location marker posts are installed at 100-metre intervals.[117]

The hectometre (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

[edit]

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

[edit]
  • 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[118]
  • 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 to September 2014
  • 169 metres – height of the Washington Monument
  • 171 metres – height of the Jeddah Flagpole, the tallest flagpole from September 2014 to 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 SzĂŠchenyi 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)[119]
  • 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[120]
  • 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[121]
  • 1,000 metres – wavelength of the lowest mediumwave radio frequency, 300 kHz

Sports

[edit]
  • 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[106]
  • 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

[edit]
  • 115.5 metres – height of the world's tallest tree in 2007, the Hyperion sequoia[122]
  • 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

[edit]

1 kilometre

[edit]
Mount Fuji is 3.776 kilometres (2.346 mi) high.

The kilometre (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

[edit]

1 kilometre (unit symbol km) is equal to:

Human-defined scales and structures

[edit]

Nature

[edit]
  • 1.5 km – distance sound travels in water in one second

Geographical

[edit]

Astronomical

[edit]

10 kilometres (1 myriametre)

[edit]
The Strait of Gibraltar is 13 km (8.1 mi) wide.

To help compare different orders of magnitude, this section lists lengths between 10 and 100 kilometres (104 to 105 metres). The myriametre[134] (sometimes also spelled myriometre; 10,000 metres) is a deprecated unit name; the decimal metric prefix myria-[87] (sometimes also written as myrio-[135][136][137]) is obsolete[88][89][90] and was not included among the prefixes when the International System of Units was introduced in 1960.

Conversions

[edit]

10 kilometres is equal to:

Distance marker on the Rhine: 36 (XXXVI) myriametres from Basel. The stated distance is 360 km (220 mi); the comma is the decimal separator in Germany.

Sports

[edit]

Human-defined scales and structures

[edit]

Geographical

[edit]

Astronomical

[edit]

100 kilometres

[edit]
The Suez Canal is 163 km (101 mi) long.

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

[edit]

A distance of 100 kilometres is equal to about 62 miles (or 62.13711922 miles).

Human-defined scales and structures

[edit]

Geographical

[edit]

Astronomical

[edit]

1 megametre

[edit]
Small planets, the Moon and dwarf planets in the Solar System have diameters from one to ten million metres. Top row: Mars (left), Mercury (right); bottom row: Moon (left), Pluto (center), and Haumea (right), to scale.

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

[edit]

1 megametre is equal to:

  • 1 E 6 m (one million metres)
  • approximately 621.37 miles
  • 1 E 12 Îźm (one trillion micrometres)
  • Side of square with area 1,000,000 km2

Human-defined scales and structures

[edit]

Sports

[edit]

Geographical

[edit]

Astronomical

[edit]

10 megametres

[edit]
Planets from Venus up to Uranus have diameters from ten to one hundred million metres. Top row: Uranus (left), Neptune (right); middle row: Earth (left), Sirius B (center), and Venus (right), to scale.

To help compare different orders of magnitude, this section lists lengths starting at 107 metres (10 megametres or 10,000 kilometres).

Conversions

[edit]

10 megametres (10 Mm) is

Human-defined scales and structures

[edit]

Geographical

[edit]

Astronomical

[edit]
  • 12.000 Mm – diameter of Sirius B, a white dwarf[153]
  • 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

[edit]
The Earth-Moon orbit, Saturn, OGLE-TR-122b, Jupiter, and other objects, to scale. Click on image for detailed view and links to other length scales.
Scale model at megametres of the main Solar System bodies

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

[edit]
13 things in the gigametre group
Upper part: Gamma Orionis, Algol B, the Sun (centre), and other objects to scale

; 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

[edit]
Rigel and Aldebaran (top left and right) compared to smaller stars, the Sun (very small dot in lower middle, with orbit of Mercury as yellow ellipse) and transparent sphere with radius of one light-minute

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

[edit]
From largest to smallest: Jupiter's orbit, red supergiant star Betelgeuse, Mars' orbit, Earth's orbit, star R Doradus, and orbits of Venus, Mercury. Inside R Doradus's depiction are the blue supergiant star Rigel and red giant star Aldebaran. The faint yellow glow around the Sun represents one light-minute. Click image to see more details and links to their scales.

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

[edit]
Eight things in the terametre group
Comparison of size of the Kuiper belt (large faint torus) with the star VY Canis Majoris (within Saturn's orbit), Betelgeuse (inside Jupiter's orbit) and R Doradus (small central red sphere) together with the orbits of Neptune and Uranus, to scale. The yellow ellipses represent the orbits of each planet and the dwarf planet Pluto.

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).

  • ≈1 Tm – 6.7 au – diameter of the red supergiant Betelgeuse based on multiple angular diameter estimates[171]
  • 1.032 Tm – 6.9 au – diameter of the blue hypergiant Eta Carinae (at optical depth 2/3)[172]
  • 1.079 Tm – 7.2 au – one light-hour
  • 1.35 Tm – 9.04 au – estimated diameter of Mu Cephei, a red supergiant (possibly hypergiant) among the largest-known stars.[173] Some estimates, however, go as high as 1.98 Tm (13.2 au).[174]
  • 1.4 Tm – 9.5 au – distance between Saturn and the Sun
  • 1.47 Tm – 9.9 au – diameter of HR 5171 A, a yellow hypergiant star.[175]
  • 1.5 Tm – 10 au – estimated diameter of VV Cephei A, a red supergiant with a blue dwarf companion.[176]
  • 2 Tm – 13.2 au – estimated diameter of VY Canis Majoris, a red hypergiant that is among the largest-known stars[177][178]
  • 2.9 Tm – 19.4 au – distance between Uranus and the Sun
  • 4.4 Tm – 29.4 au – perihelion distance of Pluto
  • 4.5 Tm – 30.1 au – distance between Neptune and the Sun
  • 4.5 Tm – 30.1 au – inner radius of the Kuiper belt
  • 5.7 Tm – 38.1 au – perihelion distance of Eris
  • 6.0 Tm – 40.5 au – distance from Earth at which the Pale Blue Dot photograph was taken.
  • 7.3 Tm – 48.8 au – aphelion distance of Pluto
  • 7.5 Tm – 50.1 au – outer radius of the Kuiper Belt

10 terametres

[edit]
Sedna's orbit (left) is longer than 100 Tm, but other lengths are between 10 and 100 Tm: Comet Hale-Bopp's orbit (lower, faint orange); one light-day (yellow spherical shell with yellow Vernal point arrow as radius); the heliosphere's termination shock (blue shell); and other arrows show positions of Voyager 1 (red) and Pioneer 10 (green). Click on image for larger view and links to other scales.

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

[edit]
The largest yellow sphere indicates one light month distance from the Sun. Click the image for larger view, more details and links to other scales.

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

[edit]
Largest circle with yellow arrow indicates one light-year from Sun; Cat's Eye Nebula on left and Barnard 68 in middle are depicted in front of Comet 1910 A1's orbit. Click image for larger view, details and links to other scales.

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 Âą 0.5 Pm = 12,000 AU = 0.2 light-year radius of Cat's Eye Nebula's inner core[180][181]
  • 3.08568 Pm = 20,626 AU = 1 deciparsec
  • 4.7 Pm = 30,000 AU = half-light-year diameter of Bok globule Barnard 68[182]
  • 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

[edit]
Objects with size order of magnitude 1e16m: Ten light-years (94.6 Pm) radius circle with yellow Vernal Point arrow; Bubble Nebula (NGC 7635), left; Dumbbell Nebula (NGC 6853), right; one light-year shell lower right with the smaller Cat's Eye Nebula (NGC_6543) and Barnard 68 adjacent.
1e16m lengths: Ten light-years (94.6 Pm) yellow shell; Sirius below right; BL Ceti below left; Proxima and Alpha Centauri upper right; light-year shell with Comet 1910 A1's orbit inside top right

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[citation needed]
  • 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

[edit]
Lengths with order of magnitude 1e17m: yellow Vernal Point arrow traces hundred light-year radius circle with smaller ten light-year circle at right; globular cluster Messier 5 in background; 12 light-year radius Orion Nebula middle right; 50-light-year-wide view of the Carina Nebula bottom left; Pleiades cluster and Bubble nebula with similar diameters each around 10 light-years bottom right; grey arrows show distances from Sun to stars Aldebaran (65 light-years) and Vega (25 light-years)

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[183][184]
  • 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

[edit]
Lengths with order of magnitude 1e18m: thousand light-year radius circle with yellow arrow and 100 light-year circle at right with globular cluster Messier 5 within and Carina Nebula in front; globular cluster Omega Centauri to left of both; part of the 1,400-light-year-wide Tarantula Nebula fills the background

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).

  • 1.2 Em – 129 light-years – diameter of Messier 13 (a typical globular cluster)
  • 1.6 Em – 172 Âą 12.5 light-years – diameter of Omega Centauri (one of the largest-known globular clusters, perhaps containing over a million stars)[185][186]
  • 3.08568 Em – 326.1 light-years – 1 hectoparsec
  • 3.1 Em – 310 light-years – distance to Canopus according to Hipparcos[187]
  • 3.9 Em – 410 light-years – distance to Betelgeuse according to Hipparcos[188]
  • 6.2 Em – 650 light-years – distance to the Helix Nebula, located in the constellation Aquarius[189]
  • 8.2 Em – 860 light-years – distance to Rigel according to Hipparcos[187]
  • 9.4 Em — 1 light-millennium – 1000 light-years

10 exametres

[edit]

To help compare different orders of magnitude, this section lists distances starting at 10 Em (1019 m or 1,100 light-years).

100 exametres

[edit]

To help compare different orders of magnitude, this section lists distances starting at 100 Em (1020 m or 11,000 light-years).

1 zettametre

[edit]

The zettametre (SI symbol: Zm) is a unit of length in the metric system equal to 1021 metres.[56] To help compare different orders of magnitude, this section lists distances starting at 1 Zm (1021 m or 110,000 light-years).

10 zettametres

[edit]

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

[edit]

To help compare different orders of magnitude, this section lists distances starting at 100 Zm (1023 m or 11 million light-years).

  • 140 Zm – 15 million light-years – distance to Centaurus A galaxy
  • 250 Zm – 27 million light-years – distance to the Pinwheel Galaxy
  • 280 Zm – 30 million light-years – distance to the Sombrero Galaxy
  • 570 Zm – 60 million light-years – approximate distance to the Virgo cluster, nearest galaxy cluster
  • 620 Zm – 65 million light-years – approximate distance to the Fornax cluster
  • 800 Zm – 85 million light-years – approximate distance to the Eridanus cluster

1 yottametre

[edit]

The yottametre (SI symbol: Ym) is a unit of length in the metric system equal to 1024 metres.[56]

To help compare different orders of magnitude, this section lists distances starting at 1 Ym (1024 m or 105.702 million light-years).

  • 1.2 Ym – 127 million light-years – distance to the closest observed gamma ray burst GRB 980425
  • 1.3 Ym – 137 million light-years – distance to the Centaurus Cluster of galaxies, the nearest large supercluster
  • 1.9 Ym – 201 million light-years – diameter of the Local Supercluster
  • 2.17 Ym – 1 light-galactic-years – 230 million light-years
  • 2.3 Ym – 225 to 250 million light-years – distance light travels in vacuum in one galactic year
  • 2.8 Ym – 296 million light-years – distance to the Coma Cluster
  • 3.15 Ym – 330 million light years – diameter of the BoĂśtes Void
  • 3.2 Ym – 338 million light-years – distance to Stephan's Quintet
  • 4.7 Ym – 496 million light-years – length of the CfA2 Great Wall, one of the largest observed superstructures in the Universe
  • 6.1 Ym – 645 million light-years – distance to the Shapley Supercluster
  • 9.5 Ym – 996 million light-years – diameter of the Eridanus Supervoid

10 yottametres

[edit]
The universe within one billion light-years of Earth

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

[edit]

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

[edit]

The ronnametre (SI symbol: Rm) is a unit of length in the metric system equal to 1027 metres.[56]

To help compare different orders of magnitude, this section lists distances starting at 1 Rm (1027 m or 105.7 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 Rm – >105.7 billion light-years – size of universe beyond the cosmic light horizon, depending on its curvature; if the curvature is zero (i.e. the universe is spatially flat), the value can be infinite (see Shape of the universe) as previously mentioned.
  • 2.764 Rm - 292.2 billion light-years – circumference of the observable universe, as it is in the shape of a sphere.
  • ≈101010122 (1012,000) light-years – the possible size of the universe after cosmological inflation.

See also

[edit]

Notes

[edit]
  1. ^ The diameter of human hair ranges from 17 to 181 Îźm 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. 101010122 is 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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    parsecs to the Orion Nebula Cluster from Very Long Baseline Array Observations&rft.volume=667&rft.issue=2&rft.pages=1161-1169&rft.date=1999&rft_id=info:arxiv/0706.2361&rft_id=https://api.semanticscholar.org/CorpusID:18192326#id-name=S2CID&rft_id=info:doi/10.1086/520922&rft_id=info:bibcode/2007ApJ...667.1161S&rft.aulast=Sandstrom&rft.aufirst=Karin M&rft.au=Peek, J. E. G.&rft.au=Bower, Geoffrey C.&rft.au=Bolatto, Alberto D.&rft.au=Plambeck, Richard L.&rfr_id=info:sid/en.wikipedia.org:Orders of magnitude (length)" class="Z3988">
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