Orders of magnitude (length)

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

Objects of sizes in different order of magnitude.

Overview

SectionRange (m)UnitExample items
≥<
Planck length–10−35ℓPQuantum foam (This is a fixed quantity, not a range.)
Subatomic–10−18amElectron, quark, string
Atomic and cellular10−1510−12fmAtomic nucleus, proton, neutron
10−1210−9pmWavelength of gamma rays and X-rays, hydrogen atom
10−910−6nmDNA helix, virus, wavelength of optical spectrum
Human scale10−610−3μmBacterium, fog water droplet, human hair's diameter[note 1]
10−31mmMosquito, golf ball, domestic cat, violin, viola, football
100103mCello, piano, human, automobile, sperm whale, football field, Eiffel Tower
103106kmMount Everest, length of Panama Canal and Trans-Siberian Railway, larger asteroid
Astronomical106109MmThe Moon, Earth, one light-second
1091012GmSun, one light-minute, Earth's orbit
10121015TmOrbits of outer planets, Solar System
10151018PmA light-year, the distance to Proxima Centauri
10181021EmGalactic arm
10211024ZmMilky Way, distance to Andromeda Galaxy
1024YmHuge-LQG, Hercules-Corona Borealis Great Wall, visible universe

Detailed list

To help compare different orders of magnitude, the following list describes various lengths between 1.6×10−35 meters and meters.

Subatomic

Factor (m) Multiple Value Item
10−35 1 Planck length 0.0000000000162 ym (1.62×10−35 m) 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 level.
10−24 1 yoctometre (ym) 2 ym (2 × 10−24 metres) 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 (7 × 10−21 metres) Effective cross section radius of high energy neutrinos[3]
310 zm (3.10 × 10−19 metres) 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

Factor (m) Multiple Value Item

10−15 1 femtometre (fm) 1.5 fm Size of an 11 MeV proton[6]
2.81794 fm Classical electron radius[7]
1.75 to 15 fm Diameter range of the atomic nucleus[1][8]
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
31 pm Radius of helium atom
53 pm Bohr radius (radius of a hydrogen atom)
10−10 100 pm 100 pm (0.1 nm) 1 Ångström (also covalent radius of sulfur atom[9])
154 pm (0.154 nm) Length of a typical covalent bond (C–C).
280 pm (0.28 nm) Average size of the water molecule, actual lengths may vary.
500 pm (0.50 nm) Width of protein α helix
10−9 1 nanometre (nm) 1 nm Diameter of a carbon nanotube[10]
2 nm Diameter of the DNA helix[11]
2.5 nm Smallest microprocessor transistor gate oxide thickness (as of January 2007)
3.4 nm Length of a DNA turn (10 bp)[12]
6–10 nm Thickness of cell membrane
10−8 10 nm 10 nm Thickness of cell wall in Gram-negative bacteria
10 nm As of 2016, the 10 nanometre was the smallest semiconductor device fabrication node[13]
40 nm Extreme ultraviolet wavelength
50 nm Flying height of the head of a hard disk.[14]
10−7 100 nm 121.6 nm Wavelength of the Lyman-alpha line[15]
120 nm Typical diameter of the human immunodeficiency virus (HIV)[16]
400–700 nm Approximate wavelength range of visible light[17]

Cellular to human scale

Factor (m) Multiple Value Item

10−6 1 micrometre (μm)

(also called one micron)

1–4 μm Typical length of a bacterium[18]
4 μm Typical diameter of spider silk[19]
7 μm Typical size of a red blood cell[20]
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[21]
10−4 100 μm 340 μm Size of a single pixel on a 17-inch monitor with a resolution of 1024×768
560 μm Thickness of the central area of a human cornea[22]
750 μm Maximum diameter of Thiomargarita namibiensis, the largest bacterium ever discovered (as of 2010)
10−3 1 millimetre (mm) 1.5 mm Length of an average flea[23]
2.54 mm 1/10th 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) 2 cm Approximate width of an adult human finger
5.4 cm x 8.6 cm Dimensions of a credit card, according to the ISO/IEC 7810 ID-1 standard
7.3–7.5 cm Diameter of a baseball, according to Major League Baseball guidelines[24]
10−1 1 decimetre (dm) 1.2 dm = 12 cm Diameter of a Compact Disk
6.6 dm = 66 cm Length of the longest pine cones, produced by the sugar pine[25]
9 dm = 90 cm Average length of a rapier, a fencing sword[26]

Human to astronomical scale

Factor (m) Multiple Value Item

1 1 metre 1 m (exactly) Since 1983, defined as length of the path travelled by light in vacuum
during a time interval of 1/299 792 458 of a second. See History of the metre for previous definitions.
2.72 m Height of Robert Wadlow, tallest known human being.[27]
8.38 m Length of a London bus (AEC Routemaster).
101 1 decametre (dam) 33 m Length of the longest known blue whale.[28]
52 m Height of the Niagara Falls.[29]
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 Axial length of the Three Gorges Dam, the largest dam in the world[30]
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.[31]

Astronomical

Factor (m) Multiple Value Item
106 1,000 km = 1 megametre (Mm) 2,390 km = 2.39 Mm Diameter of dwarf planet Pluto, formerly the smallest planet category[note 2] in the Solar System
3,480 km= 3.48 Mm Diameter of the Moon
5,200 km = 5.2 Mm Typical distance covered by the winner of the 24 Hours of Le Mans automobile endurance race
6,400 km = 6.4 Mm Length of the Great Wall of China
6,600 km = 6.6 Mm Approximate length of the two longest rivers, the Nile and the Amazon
7,821 km = 7.821 Mm Length of the Trans-Canada Highway
9,288 km = 9.288 Mm Length of the Trans-Siberian Railway, longest in the world
107 10,000 km 12,756 km Equatorial diameter of Earth
40,075 km Length of Earth's equator
108 100,000 km 142,984 km Diameter of Jupiter
299,792 km = 299 Mm Distance traveled by light in one second
384,000 km = 384 Mm Moon's orbital distance from Earth
109 1 million km = 1 gigametre (Gm) 1,390,000 km = 1.39 Gm Diameter of the Sun
4,800,000 km = 4.8 Gm Greatest mileage ever recorded by a car (3 million miles by a 1966 Volvo P-1800S, still driving)
1010 10 million km 18 million km Approximately one light-minute
1011 100 million km 150 million km = 150 Gm 1 astronomical unit (AU); mean distance between Earth and Sun
~ 900 Gm Optical diameter of Betelgeuse (~600 × Sun)
1012 1 billion km = 1 terametre (Tm) 1.4 ×109 km = 1.4 Tm Orbital distance of Saturn from Sun
1.96 ×109 km = 1.96 Tm Estimated optical diameter of VY Canis Majoris (1420 × Sun)
2.3 ×109 km = 2.3 Tm Estimated optical diameter of NML Cygni (1650 × Sun)
2.37 ×109 km = 2.37 Tm Median point of the optical diameter of UY Scuti, as of 2016 the largest known star
5.9 ×109 km = 5.9 Tm Orbital distance of Pluto from Sun
~ 7.5 ×109 km = 7.5 Tm Outer boundary of the Kuiper belt, inner boundary of the Oort cloud (~ 50 AU)
1013 10 Tm Diameter of the Solar System as a whole[1]
16.25×109 km = 16.25 Tm Distance of the Voyager 1 spacecraft from Sun (as of Feb 2009), the farthest man-made object so far[32]
62.03×109 km = 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 1.8×1011 km = 180 Tm Size of the debris disk around the star 51 Pegasi [33]
2×1011 km = 200 Tm Total length of DNA molecules in all cells of an adult human body [34]
1015 1 petametre (Pm) ~ 7.5 ×1012 km = 7.5 Pm Supposed outer boundary of the Oort cloud (~ 50,000 AU)
9.46×1012 km = 9.46 Pm
= 1 light year 		Distance traveled by light in one year; at its current speed, Voyager 1 would need 17,500 years to travel this distance
1016 10 Pm 3.2616 light-years
(3.0857×1013 km = 30.857 Pm) 		1 parsec
4.22 light-years = 39.9 Pm Distance to nearest star (Proxima Centauri)
4.37 light-years = 41.3 Pm As of March 2013, distance to nearest discovered extrasolar planet (Alpha Centauri Bc)
1017 100 Pm 20.4 light-years = 193 Pm As of October 2010, distance to nearest discovered extrasolar planet with potential to support life as we know it (Gliese 581 d)
65 light-years = 6.15×1017 m = 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) 200 light-years = 1.9 Em Distance to nearby solar twin (HIP 56948), a star with properties virtually identical to our Sun [35]
1019 10 Em 1,000 light-years = 9.46 Em or 9.46 × 1015 km Average thickness of Milky Way Galaxy[36] (1000 to 3000 ly by 21 cm observations[37])
1020 100 Em 12,000 light-years = 113.5 Em or 1.135 × 1017 km Thickness of Milky Way Galaxy's gaseous disk[38]
950 Em 100,000 light-years Diameter of galactic disk of Milky Way Galaxy[1]
1021 1 zettametre (Zm)
50 kiloparsecs Distance to SN 1987A, the most recent naked eye supernova
52 kiloparsecs = 1.62×1021 m = 1.62 Zm Distance to the Large Magellanic Cloud (a dwarf galaxy orbiting the Milky Way)
54 kiloparsecs = 1.66 Zm Distance to the Small Magellanic Cloud (another dwarf galaxy orbiting the Milky Way)
200 kiloparsecs = 6.15 Zm Diameter of the low surface brightness disc halo of the giant spiral galaxy Malin 1
1022 10 Zm 13.25 Zm = 1.4 million light years
= 600 kiloparsecs 		Radius of the diffuse stellar halo of IC 1101, one of the largest known galaxies
24 Zm = 2.5 million light-years
= 770 kiloparsecs 		Distance to Andromeda Galaxy
3.26 million light-years
=30.8 Zm = 1 megaparsec 		1 megaparsec
50 Zm (1.6 Mpc) Diameter of Local Group of galaxies
1023 100 Zm 300–600 Zm = 10–20 megaparsecs Distance to Virgo cluster of galaxies
1024 1 yottametre (Ym) 200 million light-years
= 1.9 Ym = 61 megaparsecs 		Diameter of the Local Supercluster and the largest voids and filaments.
300 million light-years
= 2.8 Ym = 100 megaparsecs 		End of Greatness
550 million light-years
~170 megaparsecs ~5 Ym 		Diameter of the Horologium Supercluster[39]
1 billion light-years
= 9.46 Ym =306 megaparsecs 		Diameter of the Pisces–Cetus Supercluster Complex, the supercluster complex where we live.
1025 10 Ym 1.37 billion light years
= 1.3×1025 m = 13 Ym 		Length of the Sloan Great Wall, a giant wall of galaxies (galactic filament).[40]
3.26 billion light years
=30.8 Ym = 1 gigaparsec 		1 gigaparsec
4 billion light years
=37.84 Ym 		Length of the Huge-LQG, a group of 73 quasars
1026 100 Ym 1×1010 light-years
= 9.5×1025 m = 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.
13.42 billion light years
=1.27×1026 m = 127 Ym 		Estimated light travel distance to UDFj-39546284, the most distant object ever observed
9.2×1010 light years
= 8.7×1026 m = 870 Ym 		Approximate diameter (comoving distance) of the visible universe[1]
1027 1000 Ym 130 billion light years
= 1.2×1027 m = 1200 Ym 		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.[41] It equivalently implies that there are at minimum 21 particle horizon-sized volumes in the universe.
[note 3] Ym megaparsecs
=  m
= Ym 		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.[42][43]
[note 3] Ym Mpc
=  m
= Ym 		Maximum size of universe after cosmological inflation, implied by one resolution of the No-Boundary Proposal[44]

less than 10 yoctometres

To help compare different orders of magnitude this section lists lengths shorter than 10−23 m (10 ym).

  • 1.6 × 10−11 yoctometres (1.6 × 10−35 metres) – the Planck length (Measures of distance shorter than this are considered nonsensical and do not make any physical sense, according to current theories of physics).
  • 1 ym – 1 yoctometre, the smallest named subdivision of the metre in the SI base unit of length, one septillionth of a metre.
  • 1 ym – length of a neutrino.
  • 2 ym – the effective cross-section radius of 1 MeV neutrinos as measured by Clyde Cowan and Frederick Reines

10 yoctometres

To help compare different orders of magnitude this section lists lengths between 10−23 metres and 10−22 metres (10 ym and 100 ym).

100 yoctometres

To help compare different orders of magnitude this section lists lengths between 10−22 m and 10−21 m (100 ym and 1 zm).

  • 100 ym – length of a top quark, one of the smallest known quarks

1 zeptometre

To help compare different orders of magnitude this section lists lengths between 10−21 m and 10−20 m (1 zm and 10 zm).

  • 2 zm – length of a preon, hypothetical particles proposed as subcomponents of quarks and leptons; the upper bound for the width of a cosmic string in string theory.
  • 2 zm – radius of effective cross section for a 20 GeV neutrino scattering off a nucleon
  • 7 zm – radius of effective cross section for a 250 GeV neutrino scattering off a nucleon

10 zeptometres

To help compare different orders of magnitude this section lists lengths between 10−20 m and 10−19 m (10 zm and 100 zm).

  • 15 zm – length of a high energy neutrino
  • 30 zm – length of a bottom quark

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

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).

  • 10 am – range of the weak force

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).

  • 100 am – all lengths shorter than this distance are not conformed in terms of size
  • 850 am – approximate proton radius

1 femtometre

The femtometre (symbol fm) is a unit of length in the metric system, equal to 10−15 metres. In particle physics, this unit is more commonly 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 (fm) 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

To help compare different orders of magnitude this section lists lengths between 10−12 and 10−11 m (1 pm and 10 pm).

10 picometres

To help compare different orders of magnitude this section lists lengths between 10−11 and 10−10 m (10 pm and 100 pm).

100 picometres

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

1 nanometre

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).

  • 10 nm – 100 angstrom
  • 10 nm – side of square of area 10−16 m2
  • 10 nm – edge of cube of area 6 * 10−16 m2 and volume 10−24 m3
  • 10 nm – radius of circle of area 3.14 * 10−16 m2
  • 10 nm – radius of sphere of area 12.56 * 10−16 m2 and volume 4.19 * 10−24 m3
  • 10 nm – the average length of a nanowire
  • 10 nm – lower size of tobacco smoke[45]
  • 11 nm – the average half-pitch of a memory cell speculated to be manufactured in 2015.
  • 13 nm – the length of the wavelength that is used for EUV lithography
  • 14 nm – Length of a porcine circovirus
  • 15 nm – Length of an antibody
  • 16 nm – technology is projected to be reached by semiconductor companies in the 2013 timeframe
  • 18 nm – diameter of tobacco mosaic virus[46] (Generally, viruses range in size from 20 nm to 450 nm.)
  • 20 nm – Length of a nanobe, could be one of the smallest forms of life
  • 20 nm to 80 nm – thickness of cell wall in Gram-positive bacteria[47]
  • 20 nm – thickness of bacterial flagellum
  • 22 nm – the average half-pitch of a memory cell expected to be manufactured at around the 2011–2011 time frame.
  • 22 nm – Smallest feature size of production microprocessors in September 2009[48]
  • 30 nm – lower size of cooking oil smoke
  • 32 nm – the average half-pitch of a memory cell manufactured at around the 2009–2010 time frame.
  • 40 nm – extreme ultraviolet wavelength
  • 45 nm – the average half-pitch of a memory cell manufactured at around the 2007–2008 time frame.
  • 50 nm – upper size for airborne virus particles
  • 50 nm – flying height of the head of a hard disk[49]
  • 65 nm – the average half-pitch of a memory cell manufactured at around the 2005–2006 time frame.
  • 58 nm – height of a T7 bacteriophage
  • 90 nm – Length of a HIV virus
  • 90 nm – Human immunodeficiency virus (HIV) (generally, viruses range in size from 20 nm to 450 nm)
  • 90 nm – the average half-pitch of a memory cell manufactured at around the 2002–2003 time frame.
  • 100 nm – Length of a Mesoporous silica.

100 nanometres

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.[50]

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

1 micrometre

The silk for a spider's web is around 5–7μm wide.

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

Fog particles are around 10–50 μm long.

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

  • 10 μm – width of cotton fibre[61]
  • 10 μm – transistor width of the Intel 4004, the world's first commercial microprocessor
  • 10 μm – mean longest dimension of a human red blood cell
  • 5–20 μm – dust mite excreta[62]
  • 10.6 μm – wavelength of light emitted by a carbon dioxide laser
  • 15 μm – width of silk fibre
  • 17 μm – minimum width of a strand of human hair[21]
  • 17.6 μm – one twip, a unit of length in typography
  • 10 to 55 μm – width of wool fibre[61]
  • 25.4 μm – 1/1000 inch, commonly referred to as 1 mil in the U.S. and 1 thou in the UK
  • 30 μm – length of a human skin cell
  • 50 μm – typical length of Euglena gracilis, a flagellate protist
  • 50 μm – typical length of a human liver cell, an average-sized body cell
  • 50 μm – length of a silt particle
  • 60 μm – length of a sperm cell
  • 70 to 180 μm – thickness of paper

100 micrometres

A paramecium is around 300 μm long.

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 (equivalent to 100 micrometers) is deprecated; the decimal metric prefix myrio-[63] is obsolete[64][65][66] and not included among the prefixes when the International System of Units was introduced in 1960.

  • 100 μm – 1/10 of a millimetre
  • 100 μm – 0.00394 inches
  • 100 μm – smallest distance that can be seen with the naked eye
  • 100 μm – average diameter of a strand of human hair[21]
  • 100 μm – thickness of a coat of paint
  • 100 μm – length of a dust particle
  • 120 μm – the geometric mean of the Planck length and the diameter of the observable universe: √8.8 × 1026 m × 1.6 × 10−35 m
  • 120 μm – diameter of a human ovum
  • 170 μm – length of the largest sperm cell in nature, belonging to the Drosophila bifurca fruit fly[67][68]
  • 181 μm – maximum width of a strand of human hair[21]
  • 100–400 μm – length of Demodex mites living in human hair follicles
  • 200 μm – typical length of Paramecium caudatum, a ciliate protist
  • 250–300 μm – length of a dust mite[69]
  • 340 μm – length of a single pixel on a 17-inch monitor with a resolution of 1024×768
  • 500 μm – typical length of Amoeba proteus, an amoeboid protist
  • 500 μm – MEMS micro-engine
  • 500 μm – average length of a grain of sand
  • 500 μm – average length of a grain of salt
  • 500 μm – average length of a grain of sugar
  • 560 μm – thickness of the central area of a human cornea[22]
  • 750 μm – diameter of a Thiomargarita namibiensis, the largest bacteria known[70]
  • 760 μm – thickness of an identification card

1 millimetre

An average red ant is about 5 mm long.

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 centimetre

An average human fingernail is about 1 cm wide.

To help compare different orders of magnitude this section lists lengths between 10−2 m and 10−1 m (1 cm and 10 cm).

1 decimetre

An adult human foot is about 28 centimetres long.

To help compare different orders of magnitude this section lists lengths between 10 centimetres and 100 centimetres (10−1 metre and 1 metre).

Conversions

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

Wavelengths

Human-defined scales and structures

  • 10.16 cm = 1.016 dm – 1 hand used in measuring height of horses (4 inches)
  • 12 cm = 1.2 dm – diameter of a Compact Disc (CD) (= 120 mm)
  • 15 cm = 1.5 dm – length of a Bic pen with cap on
  • 22 cm = 2.2 dm – diameter of a typical Association football (soccer ball)
  • 30 cm = 3 dm – typical school-use ruler length (= 300 mm)
  • 30.48 cm = 3.048 dm – 1 foot (measure)
  • 60 cm = 6 dm – standard depth (front to back) of a domestic kitchen worktop in Europe (= 600 mm)
  • 90 cm = 9 dm – average length of a rapier, a fencing sword[26]
  • 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
  • 15 cm = 1.5 dm – approximate size of largest beetle species
  • 19 cm = 1.9 dm – length of a banana
  • 29 cm = 2.9 dm – length of average human foot
  • 29.98 cm = 2.998 dm – distance light travels in one nanosecond
  • 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 pizote's tail
  • 66 cm = 6.6 dm – length of the longest pine cones (produced by the sugar pine[78])

Astronomical

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

1 metre

Leonardo da Vinci drew the Vitruvian Man within a square of side 1.83 metres and a circle about 1.2 metres in radius

To help compare different orders of magnitude this section lists lengths between one metre and ten metres. Light travels 1 metre in ​1⁄299,792,458, or 3.3356409519815E-9 of a second.

Conversions

1 metre is:

Human-defined scales and structures

  • 1 m – approximate height of the top part of a doorknob on a door
  • 1 m – diameter of a very large beach ball
  • 1.435 m – standard gauge of railway track used by about 60% of railways in the world = 4' 8½"
  • 2.5 m – distance from the floor to the celling in an average residential house[79]
  • 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 (Routemaster)

Sports

Nature

  • 1 m – height of Homo floresiensis (the "Hobbit")
  • 1.15 m – a pizote (mammal)
  • 1.37 m – average height of an Andamanese person
  • 1.63 m – (5 feet 4 inches) (or 64 inches) - height of average US female human as of 2002 (source: US Centers for Disease Control and Prevention (CDC)).
  • 1.75 m – (5 feet 8 inches) - height of average US male human as of 2002 (source: US CDC as per female above)
  • 2.5 m – height of a sunflower
  • 2.72 m – (8 feet 11 inches) - tallest known human being (Robert Wadlow)[27]
  • 3.63 m – the record wingspan for living birds (a wandering albatross)
  • 5 m – length of an elephant
  • 5.20 m – height of a giraffe[83]
  • 5.5 m – height of a Baluchitherium, the largest land mammal ever lived
  • 7 m – wingspan of Argentavis, the largest flying bird known
  • 7.50 m – approximate length of the human gastrointestinal tract

Astronomical

1 decametre

A blue whale has been measured as 33 metres long; this drawing compares its length to that of a human diver and a dolphin

To help compare different orders of magnitude this section lists lengths between 10 metres and 100 metres.

Conversions

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

Human-defined scales and structures

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)[85]
  • 20 metres – length of cricket pitch (22 yards)[86]
  • 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 (53⅓ yards)
  • 59.436 metres – width of a Canadian football field (65 yards)
  • 70 metres – typical width of soccer field
  • 91 metres – length of American football field (100 yards, measured between the goal lines)
  • 105 metres – length of football pitch (UEFA Stadium Category 3 and 4)

Nature

Astronomical

1 hectometre

The Great Pyramid of Giza is 138.8 metres high.
British driver location sign and location marker post on the M27 in Hampshire. The location marker posts are installed at 100-metre intervals[88]

To compare different orders of magnitude this section lists lengths between 100 metres and 1000 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

Sports

Nature

Astronomical

1 kilometre

Mount Fuji is 3.776 kilometres (3,776 metres) high

To help compare different orders of magnitude this section lists lengths between 1 kilometre and 10 kilometres (103 and 104 metres).

Conversions

1 kilometre (unit symbol km) is equal to:

Human-defined scales and structures

Geographical

Astronomical

10 kilometres

The Strait of Gibraltar is 13 kilometres wide

To help compare different orders of magnitude this section lists lengths between 10 and 100 kilometres (104 to 105 metres). The myriametre[105] (sometimes also spelled myriameter, myriometre and myriometer) (10,000 metres) is a deprecated unit name; the decimal metric prefix myria-[63] (sometimes also written as myrio-[106][107][108]) is obsolete[64][65][66] and not included among the prefixes when the International System of Units was introduced in 1960.

Conversions

10 kilometres is equal to:

Distance marker on the Rhine: 36 (XXXVI) myriametres from Basel. Note that the stated distance is 360 km; comma is the decimal mark in Germany.

Sports

Human-defined scales and structures

Geographical

Astronomical

100 kilometres

The Suez Canal is 163 kilometres 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

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

Human-defined scales and structures

Geographical

Astronomical

1 megametre

Small planets, the Moon and dwarf planets in our 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.

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:

Human-defined scales and structures

Sports

Geographical

Astronomical

10 megametres

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

10 megametres (10 Mm) is

Human-defined scales and structures

Geographical

Astronomical

100 megametres

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.

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

Upper part: Gamma Orionis, Algol B, the Sun (centre), underneath their darker mirror images (artist's interpretation), and other objects, to scale.

To help compare different distances this section lists lengths starting at 109 metres (1 gigametre (Gm) or 1 billion metres).

10 gigametres

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

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' depiction are the blue giant 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 Gm 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 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
  • 570 Gm – 3.8 AU – Length of the tail of Comet Hyakutake measured by Ulysses; the actual value could be much higher
  • 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

8 things in the Terameter 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.

To help compare different distances, this section lists lengths starting at 1012 m (1 Tm or 1 billion km or 6.7 astronomical units).

  • 1.079 Tm – 7.2 AU – One light-hour
  • 1.4 Tm – 9.5 AU – Distance between Saturn and the Sun
  • 1.83 Tm – 12.2 AU – Diameter of HR 5171 A, the largest known yellow hypergiant star although the latest research suggests it is a red hypergiant with a diameter about 2.1 Tm (14 AU)[131][132]
  • 2 to 3 Tm – 13.2 to 20.5 AU – Estimated diameter of VY Canis Majoris, one of the largest known stars.[133][134]
  • 2.9 Tm – 19.4 AU – Distance between Uranus and the Sun
  • 4 Tm – 26.7 AU – Previous estimated diameter of VY Canis Majoris based on direct measurements of the radius at infrared wavelengths.[135] The size was revised in 2012 through improved measurement techniques. (see above)[133]
  • 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
  • 7.3 Tm – 48.8 AU – Aphelion distance of Pluto
  • 7.5 Tm – 50.1 AU – Outer radius of the Kuiper Belt, inner boundary of the Oort Cloud

10 terametres

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 - 111.2AU - 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 – 138 AU - Distance to Voyager 1 as of November 2017
  • 25.9 Tm – 172 AU – One light-day
  • 55.7 Tm – 371 AU – Aphelion distance of the comet Hale-Bopp

100 terametres

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.
This list is incomplete; you can help by expanding it.

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

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.

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).

10 petametres

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
  • 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

100 petametres

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).
This list is incomplete; you can help by expanding it.

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[141][142]
  • 240 Pm – 25 light years – Distance to Vega
  • 260 Pm – 27 light years – Distance to Chara, a star approximately as bright as our Sun. Its faintness gives us an idea how our Sun would appear when viewed from even so close a distance as this.
  • 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

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 1400 light year wide Tarantula Nebula fills the background.

This list includes distances between 1 and 10 exametres (1018 m). To help compare different distances this section lists lengths between 1018 m (1 Em or 105.7 light years) and 1019 m (1057 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.[149]

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, or yottameter in the US, ( SI symbol: Ym) is a unit of length in the metric system equal to 1024 metres[149]

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

The universe within 1 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

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.

Distances longer than 100 Ym

  • 130 Ym – redshift 6.41 – 13 billion light years – Light travel distance (LTD) to the quasar SDSS J1148+5251
  • 130 Ym – redshift 1000 – 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; however, there might be unobserved distances that are even greater.
  • >1,000 Ym (1 kYm or xennameter in older usage) – 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

Notes

  1. ↑ According to The Physics Factbook, the diameter of human hair ranges from 17 to 181 μm. Ley, Brian (1999). "Width of a Human Hair". The Physics Factbook.
  2. 1 2 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. 1 2 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. doi:10.1175/1520-0469(1961)018<0671:AFFDSD>2.0.CO;2.

See also

References

  1. 1 2 3 4 5 6 Cliff Burgess; Fernando Quevedo (November 2007). "The Great Cosmic Roller-Coaster Ride". Scientific American (print). Scientific American, Inc. p. 55. Retrieved 2017-05-01.
  2. ↑ Carl R. Nave. "Cowan and Reines Neutrino Experiment". Retrieved 2008-12-04. (6.3 × 10−44 cm2, which gives an effective radius of about 2 × 10−24 m)
  3. ↑ Carl R. Nave. "Neutron Absorption Cross-sections". Retrieved 2008-12-04. (area for 20 GeV about 10 × 10−42 m2 gives effective radius of about 2 × 10−21 m; for 250 GeV about 150 × 10−42 m2 gives effective radius of about 7 × 10−21 m)
  4. ↑ gravitational waves that originate tens of millions of light years from Earth are expected to distort the 4 kilometre mirror spacing by about 10−18 m, less than one-thousandth the charge diameter of a proton. Equivalently, this is a relative change in distance of approximately one part in 1021. "On 14 September 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10−21." B. P. Abbott et al. (LIGO Scientific Collaboration and Virgo Collaboration), "Observation of Gravitational Waves from a Binary Black Hole Merger", Phys. Rev. Lett. 116, 061102, published 11 February 2016.
  5. ↑ Pohl R, Antognini A, Nez F, Amaro FD, Biraben F, Cardoso JM, Covita DS, Dax A, Dhawan S, Fernandes LM, Giesen A, Graf T, Hänsch TW, Indelicato P, Julien L, Kao CY, Knowles P, Le Bigot EO, Liu YW, Lopes JA, Ludhova L, Monteiro CM, Mulhauser F, Nebel T, Rabinowitz P, Dos Santos JM, Schaller LA, Schuhmann K, Schwob C, Taqqu D, Veloso JF, Kottmann F (July 2010). "The size of the proton". Nature. 466 (7303): 213–6. Bibcode:2010Natur.466..213P. doi:10.1038/nature09250. PMID 20613837.
  6. ↑ Carl R. Nave. "Scattering Cross Section". Retrieved 10 February 2009. (diameter of the Scattering Cross Section of an 11 MeV proton with a target proton)
  7. ↑ NIST. CODATA Value: classical electron radius. Retrieved 10 February 2009.
  8. ↑ H. E. Smith. "The Scale of the Universe". UCSD. Retrieved 10 February 2009. ~10−13cm
  9. ↑ Mark Winter (2008). "WebElements Periodic Table of the Elements / Sulfur / Radii". Retrieved 2008-12-06.
  10. ↑ Flahaut E, Bacsa R, Peigney A, Laurent C (June 2003). "Gram-scale CCVD synthesis of double-walled carbon nanotubes". Chemical Communications. 12 (12): 1442–3. doi:10.1039/b301514a. PMID 12841282.
  11. ↑ Stewart, Robert. "Dr". Radiobiology Software. Archived from the original on 2010-06-30. Retrieved 2015-05-20.
  12. ↑ Langevin, Dominique (2008). "Chapter 10: DNA-Surfactant/Lipid Complexes at Liquid Interfaces". In Dias, Rita S; Lindman, Bjorn. DNA Interactions with Polymers and Surfactants. Hoboken, NJ: John Wiley & Sons, Inc. p. 265. doi:10.1002/9780470286364.ch10. ISBN 978-0-470-25818-7. DNA has 20 elementary charges per helical turn over the corresponding length of 3.4nm
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  22. 1 2 Liu Z, Huang AJ, Pflugfelder SC (July 1999). "Evaluation of corneal thickness and topography in normal eyes using the Orbscan corneal topography system". The British Journal of Ophthalmology. 83 (7): 774–8. doi:10.1136/bjo.83.7.774. PMC 1723104. PMID 10381661.
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  29. 1 2 "Niagara Falls Geology Facts & Figures". Niagara Parks Commission. Archived from the original on 19 July 2011. Retrieved 29 June 2011.
  30. 1 2 "Three Gorges Dam". encyclopedia.com. Cengage Learning.
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  39. ↑ The Horologium Supercluster
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  41. ↑ https://arxiv.org/abs/astro-ph/0605709v2 How Many Universes Do There Need To Be?
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