SCALES OF MEASUREMENT VERSION 1.8
William Nielsen Brandt | [email protected]
6 8
3 10 arcseconds Angular size of a 10 M Schwarzschild black hole in M31
0:0002 arcseconds Typical VLBA resolution at 43 GHz
0:0005 arcseconds Person on the Mo on
0:001 arcseconds Typical VLBI resolution
0:001 arcseconds Typical gravitational microlensing image angular separation
0:0015 arcseconds Hipparcos satellite astrometric p ositional accuracy
0:04 arcseconds Hubble SpaceTelescope FOC optical angular resolution
0:1 arcseconds VLA largest con guration resolution at 23 GHz
0:1 arcseconds Hubble SpaceTelescope WFC optical angular resolution
0:15 arcseconds 1 meter optical re ector yellow light di raction limit
0:5 arcseconds WHT MARTINI guide star system resolution
0:6 arcseconds Rough optical telescop e atmospheric seeing limit
0:8 arcseconds Angular diameter of Europa
1 arcseconds AXAF X-ray satellite angular resolution goal
1:32 arcseconds Yearly prop er motion of Sirius
1:75 arcseconds Gravitational de ection of a lightray which grazes the Sun
2:9 arcseconds Angular diameter of a M31 sized galaxy at z =0:5 in optical light
5 arcseconds ROSAT X-ray satellite HRI angular resolution
8 arcseconds Angular separation of the gravitationally lensed quasar 0957+561
25 arcseconds ROSAT X-ray satellite PSPC angular resolution
36 arcseconds Angular diameter of Jupiter
120 arcseconds Human eye resolution
120 arcseconds Typical optical telescop e eld of view
150 arcseconds Rough Crab Nebula radius
210 arcseconds Rough Cir X-1 radio nebula radius
400 arcseconds Cluster imprint on the cosmic microwave background radiation
480 arcseconds OVRO 5.5 meter 32 GHz telescop e resolution
700 arcseconds Jo drell bank 250 fo ot 1 420:4 MHz telescop e resolution
1 200 arcseconds ROSAT X-ray satellite HRI eld of view radius
1 500 arcseconds ASCA X-ray satellite GIS eld of view radius
1 865 arcseconds Angular diameter of the Mo on at its mean distance
1 800 arcseconds 100 Mp c structure imprint on the cosmic microwave background radiation
1 922 arcseconds Angular diameter of the Sun at its mean distance
2 700 arcseconds Largest dimension of W50 ARAA 22, 524
3 100 arcseconds Maximum angular scale of causal connection on the cosmic microwave background radiation
3 600 arcseconds ROSAT X-ray satellite PSPC eld of view radius
10 800 arcseconds Angular diameter of the LMC
14 400 arcseconds Angular diameter of M31 in optical light
19 800 arcseconds Palomar Optical Sky Survey plate eld of view
25 200 arcseconds COBE DMR resolution limit
1
Gh
44 2
5 10 seconds Planck-Wheeler time =
5
c
h
24
4 10 seconds Typical lifetime of strong interaction resonance =
2
m c
p
h
21
8 10 seconds Electron light crossing time =
2
m c
e
13
1 10 seconds Typical p erio d of vibration of an atom in a solid
13
1 10 seconds Typical X-ray line electric dip ole radiative transition time
9
1:6 10 seconds Typical hydrogen 2p!1s radiative transition time electric dip ole one photon pro cess
4
8 10 seconds Mass shedding minimum spin p erio d for a neutron star
3
1:6 10 seconds Spin p erio d of PSR 1957+20
0:12 seconds Typical hydrogen 2s!1s radiative transition time strictly forbidden two photon pro cess 1
10 seconds Median duration of a classical -ray burst
887 seconds Mean life of a neutron in free space
2 000 seconds Sun dynamic time scale
4
8:6 10 seconds Earth rotation time
7
3:2 10 seconds Earth orbit time around the Sun
9
1:6 10 seconds Typical time b etween Milky Way sup ernovae
11
1:9 10 seconds Carb on-14 half-life
12
3 10 seconds Rough lifetime of a sup ernova remnant
13
1:5 10 seconds Typical HMXB evolution time
13
3 10 seconds Rough time for evolution of a biological sp ecies
14
1:6 10 seconds Main sequence lifetime for a 30 M star
14
3 10 seconds Hydrogen 21 cm spin ip time
14
3 10 seconds Rough Lyapunov time of the solar system
14
6:3 10 seconds Sun thermal time scale
15
1:3 10 seconds E-folding time for a black hole accreting at the Eddington rate with an eciency of 0.1
15
1:9 10 seconds Main sequence lifetime for a 5 M star
15
2 10 seconds Timescale for Los Angeles to pass San Francisco via continental drift
15
2:4 10 seconds Typical LMXB evolution time
15
7:3 10 seconds Orbit time for sun around galaxy center
16
1:1 10 seconds PSR 1913+16 orbital gravitational radiation coalescence timescale
16
2 10 seconds Rough sup ernova biological extinction time
16
6 10 seconds Minimum age of PSR J0437{4715 ApJ 411, L85
16
6 10 seconds Time for galaxy to cross a cluster
16
7 10 seconds Radial p erio d of the orbit of the Magellanic Clouds MNRAS 198, 718
17
1:1 10 seconds Primeval slime to man time
17
1:5 10 seconds Age of Earth and Sun
17
1:5 10 seconds Uranium-238 half-life
17
2:7 10 seconds Lo ok back time to z =1
17
3 10 seconds Main sequence lifetime for a 1 M star
17
3:3 10 seconds Lo ok back time to z =2
17
3:3 10 seconds Sun nuclear time scale
17
3:7 10 seconds Lo ok back time to z =4
17
3:8 10 seconds Rough age of the Milky Way
17
3:8 10 seconds Lo ok back time to the z =4:897 quasar PC 1247+3406
17
4 10 seconds Rough age of 47 Tucanae an old globular cluster
2
17
4:1 10 seconds Age of the universe =
3H
0
18
2:5 10 seconds Globular cluster evap oration time
25
3 10 seconds Galaxy dynamical relaxation timescale
27
3 10 seconds Earth/Sun orbital gravitational radiation coalescence timescale
39
1 10 seconds Lower limit on the proton lifetime
73
4:7 10 seconds 1M black hole Hawking evap oration time
1
Gh
2 35
1:6 10 meters Planck-Wheeler length =
3
c
35
2 10 meters Rough p ostulated sup erstring size
24
1 10 meters E ective 1 MeV neutrino radius
22
1:6 10 meters Radius of a 10 M star squeezed down to the Planck-Wheeler density
2
e
18
1:5 10 meters Classical proton radius =
2
4 m c
0 p
h
17
1:6 10 meters W Compton wavelength = = rough weak force length
m c
W
17
4 10 meters LIGO 4 km gravity-wave detector needed sensitivity
h
15
= rough proton fuzziness length 1:3 10 meters Proton Compton wavelength =
m c
p
1
15
3
1:44 10 A meters Nuclear radius
2
e
15
2:8 10 meters Classical electron radius =
2
4 m c
0 e 2
h
15
8:8 10 meters -meson Compton wavelength = = attractive strong force length
m c
12
1:2 10 meters 1 MeV -raywavelength
h
12
2:4 10 meters Electron Compton wavelength = = rough electron fuzziness length
m c
e
2
h
11
0
5:3 10 meters Bohr radius =
2
m e
e
10
2:6 10 meters Copp er atom spacing in solid copp er
10
3:5 10 meters H O molecular diameter
2
10
4 10 meters ROSAT X-ray satellite mirror rms surface error
9
1:2 10 meters 1keV X-raywavelength
9
3 10 meters Typical mean nucleon spacing during primordial nucleosynthesis
9
3:4 10 meters DNA double helix turn length
8
6 10 meters Typical rms surface error of a Keck telescop e mirror
8
7:0 10 meters Molecular mean free path in the atmosphere
7
1 10 meters Typical size of a virus
7
3 10 meters Interstellar dust grain size
7
5 10 meters Optical photon wavelength
6
4 10 meters Typical size of a cell
4
2 10 meters Small dust particle size
0:03 meters Lunar laser ranging accuracy Science 265, 482
0:068 meters Unraveled human DNA strand length
1:8 meters Man
30 meters Blue Whale
3 700 meters Mean o cean depth
4 000 meters Error in our knowledge of the distance to Jupiter
5 500 meters Rough radius of Halley's comet
8 847 meters Height of MountEverest
10 000 meters Neutron star radius
10 000 meters Typical asteroid radius
10 000 meters Typical comet radius
11 032 meters Depth of the Mariana Trench
12 000 meters Height of trop osphere
12 000 meters Typical airliner cruising altitute
30 000 meters Typical thickness of the Earth's crust
5
5:5 10 meters Height of the ASCA X-ray satellite orbit
5
9 10 meters Height of the COBE satellite orbit
6
3:2 10 meters Length of the Great Wall of China
6
6:3 10 meters Radius of the Earth
7
4:2 10 meters Geostationary satellite orbit height
7
7:1 10 meters Radius of Jupiter
7
9 10 meters Distance to the Earth's solar wind b ow sho ck
8
3:8 10 meters Distance to the Mo on
8
7:0 10 meters Radius of the Sun
9
1 10 meters Typical X-ray binary accretion disk circularization radius
9
1:7 10 meters 5M star main sequence radius
9
7 10 meters Typical stando radius of Jupiter's solar wind b ow sho ck
11 8
1:47 10 meters Event horizon radius for a 10 M maximally rotating Kerr black hole
11
1:50 10 meters Earth/Sun mean distance
11
1:5 10 meters Radius of the red giant Mira at minimum light
11
3 10 meters Radius of the red giant Mira at maximum light
11
5 10 meters Radius of the 20 M red sup ergiant Betelgeuse at maximum light
12
5:91 10 meters Pluto/Sun mean distance
13
1:5 10 meters Exp ected distance to the solar wind termination sho ck
14
2 10 meters Rough stellar separation in the central parsec of the Milky Way
14
4 10 meters Rough stellar separation in a globular cluster 3
14
4 10 meters Seyfert galaxy characteristic broad line region radius
15
2 10 meters Rough Oort Cloud/Sun distance
15
9:46 10 meters 1 light-year
16
3:08 10 meters 1 parsec
16
4 10 meters Nearest nonsolar star to Earth
16
4:5 10 meters Rough Crab Nebula radius
17
1:6 10 meters Stromgren sphere radius for an O5 star
17
3 10 meters Rough Cir X-1 radio nebula radius
17
3 10 meters Rough sup ernova biological extinction distance PASP 106, 689
17
5 10 meters Typical interstellar medium cloud size
18
1:4 10 meters Hyades op en cluster distance
18
1:5 10 meters Trigonometric parallax distance determination limit
18
1:5 10 meters Typical globular cluster radius
18
2 10 meters Rough radius of the lo cal interstellar hot gas bubble
18
2 10 meters Largest dimension of W50 ARAA 22, 524
18
2:6 10 meters Rough distance to PSR J0108 1431
18
5 10 meters Scale height of the Milky Wayinterstellar medium
18
5 10 meters Seyfert galaxy characteristic narrow line region radius
18
5:2 10 meters Distance to the 20 M red sup ergiant Betelgeuse will go sup ernova within 10 000 years
19
2 10 meters Characteristic height of the Milky Way main disk
19
6 10 meters Typical dwarf galaxy radius
19
6:6 10 meters Distance to the Crab Nebula
20
2 10 meters Estimated distance to Cir X-1
20
2:4 10 meters Distance from Sun to galactic center
21
1:5 10 meters Distance to the LMC
21
2 10 meters Rough Milky Way dark matter halo radius
21
6 10 meters Typical Ly- galaxy neutral hydrogen radius
22
1 10 meters Typical active galaxy jet length
22
1 10 meters Length of the \sup erantennae" of IRAS 19254{7245
22
1:9 10 meters Distance to M31
22
3 10 meters Radius of the core of the Virgo cluster of galaxies
22
4 10 meters Rough Lo cal Group radius
22
9:2 10 meters Cepheid variable distance determination limit via ground observations
23
1:2 10 meters Distance to the Circinus galaxy
23
5 10 meters Rough b oundary b etween the nonlinear and linear gravitational collapse regimes
23
7 10 meters Distance to the z =0:0036 Seyfert 2 NGC 1068
23
7 10 meters Distance to the center of the Virgo cluster of galaxies
23
9 10 meters Characteristic maximum travel length of a yo cto-eV cosmic ray due to pion
pro duction o the microwave background
24
2:3 10 meters Shapley sup ercluster radius
24
3 10 meters Typical length scale prob ed by the Harvard/Smithsonian CfA redshift survey
24
4:1 10 meters Luminosity distance to the z =0:022 Coma cluster of galaxies
25
1:5 10 meters Typical length scale prob ed by the Lick survey
25
3:0 10 meters Luminosity distance to the z =0:158 quasar 3C273
25
3 10 meters Typical length scale prob ed by the 4C radio galaxy survey
25
3 10 meters Schwarzschild radius of a singularity with the mass of a critical density universe
26
5:5 10 meters Luminosity distance to the z =2:286 ultraluminous IRAS galaxy IRAS F10214+4724
27
1:3 10 meters Luminosity distance to the z =4:897 quasar PC 1247+3406
9 1
1 10 ms Sea o or spreading rate
9 1
1:6 10 ms Average slip rate of the San Andreas fault
8 1
1 10 ms Typical rainfall rate in a semi-arid climate
8 1
2 10 ms Grass growth rate
6 1
3 10 ms Typical glacial advance rate 4
3 1
1 10 ms Equivalent radial velo city resolution of pulsar pulse arrival time analysis
1
1:3 ms Human walking sp eed
1
3 ms Radial velo city accuracy of high precision Doppler sp ectroscopy
1
13 ms Sp eed of the re ex motion induced on the Sun by Jupiter
1
25 ms Car sp eed
1
60 ms Radial velo city semiamplitude of 51 Pegasi due to its planet
1
100 ms Typical sp eed of an electric pulse in the nervous system
1
330 ms Sound sp eed in air
1
480 ms Earth's atmosphere molecular rms velo city
1
600 ms Fighter jet sp eed
1
2 380 ms Escap e velo city from Mo on's surface
1
10 000 ms Typical longitudinal seismic wavevelo city in the Earth's mantle
1
11 000 ms Escap e velo city from the Earth's surface
1
20 000 ms Globular cluster stellar velo city disp ersion
1
29 000 ms Earth's motion around the Sun
1
40 000 ms Globular cluster stellar escap e velo city
5 1
1 10 ms Typical Galactic pulsar vertical velo city comp onent
5 1
1 10 ms Average sp eed of the initial stroke of a lightning ash
5 1
2:2 10 ms Rotational velo city of the Sun around the Milky Way's center
5 1
3 10 ms Orbital sp eed of PSR 1913+16
5 1
3 10 ms Rough velo city of Geminga's prop er motion
5 1
3:65 10 ms Motion of the solar system barycenter relative to the cosmic microwave background
5 1
4:1 10 ms Orbital sp eed of Cen X-3
5 1
6:2 10 ms Escap e velo city from the Sun's surface
5 1
6:2 10 ms Escap e velo city from the Milky Way for ob jects in the solar neighb orho o d ARAA 29, 429
5 1
6:22 10 ms Motion of the Lo cal Group relative to the cosmic microwave background
5 1
8 10 ms Typical galaxy cluster galaxy velo city disp ersion
6 1
2 10 ms Sp eed of n =1 hydrogen electron = Z c
6 1
5 10 ms Young months old sup ernova ejecta
7 1
1:2 10 ms Velo city of the wind streaming out from H1413+117 \Cloverleaf " Nature 371, 559
7 1
7:8 10 ms SS433 jet sp eed
8 1
1:4 10 ms Keplerian orbital velo city at the surface of a neutron star
8 1
2 10 ms Escap e velo city from neutron star surface
8 1
2:8 10 ms Ejecta from GRS 1915+105 Nature 371, 46
8 1
2:998 10 ms Lightinavacuum
8 1
3:7 10 ms Apparent sup erluminal motion of the ejecta from GRS 1915+105 Nature 371, 46
9 1
6 10 ms Apparent sup erluminal motion of the jet from the z =2:16 quasar 0836+710
10 1
2:7 10 ms Apparent sup erluminal motion of the jet from the z =0:940 BL Lac AO 0235+164 may b e lensed
36
4:2 10 kilograms Mass equivalent of a green light photon
36
9:1 10 kilograms Electron antineutrino upp er mass limit
31
4:8 10 kilograms Muon neutrino upp er mass limit
31
9:11 10 kilograms Electron mass
29
5:5 10 kilograms Tau neutrino upp er mass limit
27
1:67 10 kilograms Proton mass
27
9 10 kilograms Bottom quark mass
26
4:8 10 kilograms Mean mass of atmosphere molecule
25 2
1:4 10 kilograms W mass 80:22 0:22 GeV/c
25 0 2
1:6 10 kilograms Z mass 91:187 0:007 GeV/c
25
2 10 kilograms Favored Higgs b oson mass
25 2
3:1 10 kilograms Top quark mass 176 13 GeV/c
25
4 10 kilograms DNA nucleotide
22
1 10 kilograms Typical protein molecule mass
21
5 10 kilograms E. Coli rib osome 5
16
1 10 kilograms Interstellar dust grain mass
15
8 10 kilograms Rough mass of a human DNA molecule
13
7 10 kilograms Typical mass of a cell
1
hc
8 2
2:2 10 kilograms Planck-Wheeler mass =
G
5
1 10 kilograms Typical mosquito mass
0:02 kilograms Typical gold sh mass
70 kilograms Typical human mass
70 kilograms Lower limit to the allowed mass for a Sumo wrestler
100 kilograms Meteorite mass b efore entry into Earth's atmosphere
420 kilograms ASCA X-ray satellite mass
900 kilograms Compton Gamma-Ray Observatory satellite mass
1 000 kilograms Car
2 200 kilograms ISO infrared satellite mass at launch
10 000 kilograms Tyrannosaurus Rex
11
5 10 kilograms Initial mass of a primordial black hole with evap oration time equal to the universe's age
13
1 10 kilograms Typical comet mass
14
3 10 kilograms Typical mountain mass
16
1:1 10 kilograms Sup erterranean biomass of Earth o cean organisms are included
18
5:3 10 kilograms Total mass of Earth's atmosphere
19
3 10 kilograms Typical asteroid mass
21
1:4 10 kilograms Total mass of Earth's o ceans
22
4:8 10 kilograms Mass of Europa
22
7:3 10 kilograms Mass of the Mo on
24
2 10 kilograms Rough Oort cloud mass
24
5:98 10 kilograms Mass of the Earth
27
1:9 10 kilograms Mass of Jupiter
29
1:6 10 kilograms Minimum mass to fusion burn hydrogen
29
4 10 kilograms Rough mass of MACHO and EROS microlensing ob jects
30
1:99 10 kilograms Mass of the Sun
30
2:8 10 kilograms Chandrasekhar mass maximum mass for a white dwarf
30
6:0 10 kilograms Opp enheimer-Volko mass maximum mass for a neutron star
31
1:2 10 kilograms Minimum mass of the unseen ob ject in GS2023+338/V404 Cygni
31
4 10 kilograms Rough stellar mass ab ove which the evolutionary endp oint is a black hole
32
1:0 10 kilograms Mass of the most massive memb er of Plaskett's star
32
1:2 10 kilograms Rough mass at which a star b ecomes unstable to pulsations
33
2 10 kilograms Typical interstellar cloud mass
36
1 10 kilograms Typical mass of a globular cluster
36
5 10 kilograms Approximate mass of the Milky Way central black hole
37
1 10 kilograms Rough baryonic Jeans mass immediately after decoupling
39
4 10 kilograms Rough mass of the SMC
40
2 10 kilograms Rough mass of the LMC
42
2:6 10 kilograms Rough mass of the visible and dark matter in the Milky Way ApJ 345, 759
44
1:3 10 kilograms Rough mass of the stars in the Coma galaxy cluster
44
6:4 10 kilograms Rough mass of the X-ray gas in the Coma galaxy cluster
45
2:7 10 kilograms Rough virial mass of the Coma galaxy cluster
45
6 10 kilograms Rough virial mass of the Ab ell 2163 galaxy cluster
48
2 10 kilograms Rough baryonic Jeans mass immediately b efore decoupling
49
1:4 10 kilograms Rough total mass in spiral galaxies
49
2 10 kilograms Rough total baryonic and nonbaryonic mass in galaxy clusters
49
3 10 kilograms Rough total mass in elliptical and spheroidal galaxies
49
8 10 kilograms Rough total mass of visible matter in the universe
51
1 10 kilograms Rough total baryon mass predicted by primordial nucleosynthesis
52
2 10 kilograms Rough total mass of a critical density universe 6
38 3
2 10 kg m E ective density of the 100-300 MHz radio background
35 3
1 10 kg m E ective density of the 1{10 MeV -ray background
35 3
8 10 kg m E ective density of the 2{100 keV X-ray background
33 3
1:1 10 kg m Upp er limit to the e ective density of the gravitational wave background
32 3
1 10 kg m E ective density of the starlight released in a Hubble time
31 3
4:6 10 kg m E ective density of the cosmic microwave background radiation
29 3
2 10 kg m Smo othed density of visible galactic material throughout universe
28 3
2 10 kg m Smo othed baryon density predicted by primordial nucleosynthesis
2
3H
27 3
0
4:7 10 kg m Critical density of the universe =
8G
24 3
2 10 kg m Typical gas in a cluster of galaxies
21 3
3 10 kg m Typical gas in the interstellar medium of the Milky Way
21 3
7 10 kg m Dynamically inferred Milky Way disk density
20 3
5 10 kg m Typical density of the gas in the central kiloparsec of an interacting or starburst galaxy
9 3
1 10 kg m Best ro om temp erature vacuum achieved on Earth
4 3
1:7 10 kg m Mean densityofAntares 19 M
3
1:3 kg m Density of air
3
700 kg m Mean density of Saturn
3
1 000 kg m Densityofwater
3
1 300 kg m Mean density of Jupiter
3
1 400 kg m Mean density of the Sun
3
3 300 kg m Mean density of the Mo on
3
5 500 kg m Mean density of the Earth
3
7 860 kg m Density of iron
3
19 300 kg m Density of gold
7 3
5 10 kg m Typical white dwarf mean density
10 3
3 10 kg m Typical white dwarf central density
12 3
1:1 10 kg m Inverse decay threshold
14 3
4:3 10 kg m Neutron drip density
17 3
6 10 kg m Nuclear density
18 3
1 10 kg m Typical neutron star central density
5
c
96 3
5 10 kg m Planck-Wheeler density, at which quantum gravitational e ects b ecome imp ortant=
2
G h
25
6 10 joules Lamb-Retherford shift
25
9:5 10 joules 21.049 cm photon|hyp er ne shift
22
4 10 joules Molecular rotation transition
21
4 10 joules kT = translational kinetic energy of atmosphere gas molecule
ro om
21
7 10 joules Donor level/conduction band gap in a dop ed semiconductor
20
3 10 joules Molecular vibration transition
19
1:6 10 joules Valence band/conduction band gap in a semiconductor
19
2:2 10 joules Bond energy of an organic substance with half-life 30 000 years
19
3:8 10 joules Green light photon
19
9 10 joules Valence band/conduction band gap in an insulator
18
1:1 10 joules Fermi energy in copp er = depth of Fermi sea
18
1:1 10 joules Positronium ionization energy
18
2:2 10 joules Hydrogen n = 1 binding energy
16
1:6 10 joules 1keV X-ray
15
1:5 10 joules Hydrogenic iron n = 1 binding energy
14
8:18 10 joules Electron rest mass
13
1:6 10 joules 1 MeV -ray
13
1:6 10 Z Z joules Coulomb barrier height
1 2
12
1:3 10 joules Nucleon binding energy
12 1 4
4:3 10 joules Energy from 4 H ! He
10
1:50 10 joules Proton rest mass 7
7
1:6 10 joules Particle kinetic energy in a 1 TeV accelerator
10 joules Well hit tennis ball
51 joules Fly's Eye most energetic cosmic rayevent
5
2 10 joules Energy from a light bulb burning for 1 hour
7
2 10 joules Rough energy from a 1 kilogram meal
9
4:2 10 joules Explosion energy of 1 ton of TNT
10
2 10 joules Rough energy of a lightning ash
11
2 10 joules Rough human total energy output in a lifetime
14
1:5 10 joules Typical atomic b omb explosion energy
16
6 10 joules Tunguska 50 m diameter meteorite impact energy
17
1 10 joules Powerful H-b omb explosion energy
17
3 10 joules Elastic wave energy release from a large M =8:5 earthquake
17
5 10 joules Explosion energy of Krakatoa
18
3 10 joules Sup erman ying at 70 p er cent of light sp eed
18
9 10 joules USA electricity usage in 1986
19
5 10 joules Rough explosion energy of the LakeToba eruption in Sumatra
22
2:5 10 joules Energy from the comet Sho emaker-Levy 9 fragment G impact on Jupiter
23
4 10 joules K-T 10 km diameter meteorite impact energy
24
1 10 joules Power released byanevap orating black hole during the last second of its life
29
2:1 10 joules The Earth's rotational energy
31
3 10 joules The Earth's total heat content
34
7 10 joules Total rotational energy of the planets
35
2:5 10 joules Rotational energy of the Sun
36
3 10 joules Gravitational internal binding energy of Jupiter
37
6 10 joules NovaPersei outburst
41 1
3 10 joules A 450 km s neutron star kick
43
3 10 joules Energy needed to make the lo cal bubble
1
44 2
1:3 10 joules Total radiant energy from the Sun | 0:007 M c
10
44
3 10 joules Energy in photons from a typ e I I sup ernova explosion
45
1 10 joules Rough total energy from a cosmological -ray burst
46
3 10 joules Energy in neutrinos from a typ e I I sup ernova explosion
53
2 10 joules Typical gravitational binding energy of a galaxy
54
2 10 joules Typical magnetic and kinetic energy in a large radio lob e Shu 311
54 8 2
5:2 10 joules Rotational energy of a 10 M maximal Kerr black hole = 0:29M c
57
5 10 joules Typical gravitational binding energy of a cluster of galaxies
7 1
2 10 Jkg Eciency of the metab olism of fo o d
13 1
1:3 10 Jkg Eciency of dropping matter onto a white dwarf
14 1
6:3 10 Jkg Eciency of fusion burning hydrogen
15 1
5:1 10 Jkg Slowly spiraling accretion ontoaSchwarzschild black hole
15 1
7:5 10 Jkg Shakura-Sunyaev eciency for accretion onto a Newtonian \black hole"
15 1
8 10 Jkg Eciency of dropping matter onto a neutron star
16 1
2:6 10 Jkg Slowly spiraling prograde accretion onto a realistically maximally rotating Kerr black hole
16 1
3:8 10 Jkg Slowly spiraling prograde accretion onto a theoretically maximally rotating Kerr black hole
16 1
8:99 10 Jkg Eciency of matter-antimatter annihilation
6
4 10 watts Average energy output from 1 kilogram of the Milky Way
3
1 10 watts Optical disc player laser
6 watts Amateur short wave radio transmitter
60 watts Light bulb
100 watts Gravitational wavepower from the Earth-Sun system
150 watts Human b eing under normal conditions
750 watts Maximum long duration horse output
1 500 watts Typical replace re 8
20 000 watts Car
4
7 10 watts Soft X-ray scattered lunar luminosity
5
1 10 watts Running Tyrannosaurus Rex
8
3 10 watts Nuclear p ower reactor
8
3 10 watts Mo derate thunderstorm electrical p ower generation rate
9
1:3 10 watts Ho over dam
9
4 10 watts Soft X-rayJovian auroral luminosity
11
3 10 watts USA average electricity usage rate in 1986
13
1 10 watts Solar radio luminosity
13
8 10 watts Powerful nanosecond pulse laser
17
1:7 10 watts Insolation of Earth
20
1 10 watts X-ray luminosity of the quiet Sun
23
1 10 watts Typical white dwarf luminosity
24
8 10 watts Gravitational wave radiation from PSR 1913+16
26
3:9 10 watts Solar luminosity
26
5 10 watts The 2{10 keV ux of the cataclysmic variable FO Aquarii
28
1 10 watts Typical X-ray luminosity of an X-ray pulsar
28
1 10 watts X-ray luminosity asso ciated with Sgr A
28
3:5 10 watts Rotational energy loss rate from the Geminga pulsar
28
4:3 10 watts Megamaser in NGC 4258
29
2:4 10 watts 5M star on main sequence
30
4 10 watts Cygnus X-1 X-ray luminosity
30
5:5 10 watts Luminosity of the 20 M red sup ergiant Betelgeuse at maximum light
31
1 10 watts Crab Nebula energy output
31
2 10 watts Eddington limit for a 1.4 M neutron star
31
3 10 watts Typical luminosity of Cir X-1 in zero phase
31
3 10 watts Typical luminosity of GRS 1915+105 in outburst Nature 371, 46
33
1 10 watts Rough luminosity of Eta Carinae in April 1843
35
5 10 watts Typ e I I sup ernova p eak photon luminosity
36
3 10 watts Milky Way
38
1:5 10 watts Coma cluster X-ray gas luminosity
1
39 8
1 10 watts 10 M black hole accreting at of the Eddington limit
10
39
1 10 watts Typical quasar luminosity
40
1 10 watts Rough luminosity of the quasar 3C273
41
2 10 watts Rough luminosity of the z =2:286 ultraluminous IRAS galaxy IRAS F10214+4724
43
6 10 watts Rough luminosity of a cosmological -ray burst
46
2 10 watts Rough luminosity of all the stars in the universe
48
1 10 watts Core collapse neutrino luminosity ofatyp e I I sup ernova QJRAS 30, 423
7
7 10 kelvins Laser co oling of cesium atoms
5
1:3 10 kelvins Cosmic microwave background quadrup ole anisotropy
4
5 10 kelvins Typical Sunyaev-Zel'dovich cosmic microwave background decrement
3
3:3 10 kelvins Cosmic microwave background dip ole anisotropy
0:01 kelvins Typical limit of liquid helium dilution co oling
0:3 kelvins Typical limit of liquid helium evap oration co oling
4
2:17 kelvins Liquid He sup er uid transition temp erature
2:726 kelvins Cosmic microwave background temp erature to day
3
3:20 kelvins Liquid He b oiling p oint
4 kelvins Typical limit of Joule-Thomson e ect co oling
4
4:18 kelvins Liquid He b oiling p oint
6 kelvins Typical noise temp erature of a HEMT receiver at 30 GHz
12 kelvins Lanthanum under pressure sup erconductivity critical temp erature highest for a pure element
20 kelvins Liquid H b oiling temp erature
2
77 kelvins Liquid N b oiling temp erature
2 9
133 kelvins Mercury-barium-calcium-copp er oxide comp ound sup erconductivity critical temp erature
273 kelvins Water freezing temp erature
311 kelvins Human surface temp erature
373 kelvins Water b oiling temp erature
388 kelvins Brimstone melting temp erature|upp er limit to the temp erature of Hell
506 kelvins Pap er burning temp erature
740 kelvins Typical surface temp erature of Venus
1811 kelvins Melting temp erature of iron
3000 kelvins Cosmic microwave background temp erature at decoupling
5770 kelvins Solar e ective temp erature
5
5 10 kelvins Surface temp erature of the Geminga pulsar
6
3 10 kelvins Polar cap temp erature of the Geminga pulsar
6
3 10 kelvins Typical fusion exp eriment
7
1:4 10 kelvins Center of the Sun
7
1:5 10 kelvins Changeover temp erature from the proton-proton chain to the CNO cycle
7
2:7 10 kelvins Center of a 5 M star
7
5 10 kelvins Typical gas temp erature in a cluster of galaxies
8
1 10 kelvins Typical cataclysmic variable accretion column sho ck temp erature
8
4 10 kelvins Characteristic temp erature for electron-p ositron pair pro duction
8
4 10 kelvins Minimum primordial nucleosynthesis temp erature
8
5 10 kelvins Inner accretion disc temp erature of Cyg X-1
c
8
7 10 kelvins Thermal electrons b ecome relativistic v =
e
2
9
1 10 kelvins Maximum primordial nucleosynthesis temp erature
9
1 10 kelvins Rough sup erconductivity critical temp erature in a neutron star
10
1 10 kelvins Rough plasma pair catastrophe temp erature
10
3 10 kelvins Core collapse temp erature of a sup ernova QJRAS 30, 424
15
3 10 kelvins Rough electroweak uni cation temp erature
13 2
7 10 Nm Typical gas pressure in a cluster of galaxies
12 2
5 10 Nm Pressure in the b est vacuum achieved on Earth
6 2
5 10 Nm Solar radiation pressure at the Earth
5 2
1 10 Nm Pressure of a sound wave at the human threshold of hearing
2
0:2 Nm Solar radiation pressure at the surface of the Sun
2
30 Nm Pressure of a sound wave at the human threshold of pain
4 2
1 10 Nm Mean human arterial blo o d overpressure
4 2
1:5 10 Nm Standing p erson
5 2
1 10 Nm Typical atmospheric pressure
6 2
1:5 10 Nm High pressure bicycle tire
7 2
2 10 Nm Typical scuba tank pressure
7 2
9 10 Nm Peak pressure of a st on concrete during a karate strike
8 2
1:1 10 Nm Pressure at the b ottom of the Marianas trench
9 2
6 10 Nm Pressure needed for the natural crystalization of diamonds
10 2
1 10 Nm Conventional high pressure lab oratory press
11 2
2 10 Nm Peak pressure from a diamond anvil pressure cell
11 2
5 10 Nm Central pressure of the Earth
12 2
4 10 Nm Central pressure of Jupiter
13 2
2 10 Nm Radiation pressure at the center of the Sun
16 2
2:7 10 Nm Central pressure of the Sun
23 2
1 10 Nm Typical central pressure of a white dwarf
34 2
1 10 Nm Typical central pressure of a neutron star
12 2
1 10 Wm Threshold of hearing 0 dB
11 2
1 10 Wm Rustle of leaves 10 dB
10 2
1 10 Wm Quiet whisp er 20 dB 10
9 2
1 10 Wm Soft music 30 dB
8 2
3 10 Wm Average residence 45 dB
6 2
1 10 Wm Background music 60 dB
6 2
3 10 Wm Ordinary conversation at 0.5 meters 65 dB
5 2
1 10 Wm Busy street trac 70 dB
5 2
3 10 Wm Typical factory 75 dB
3 2
1 10 Wm Rough b oundary of unsafe sound levels 90 dB
2 2
1 10 Wm Lawn mower 100 dB
2
1 Wm Loud ro ckmusic concert 120 dB
2
10 Wm Threshold of pain 130 dB
2
100 Wm Jet plane at 30 meters 140 dB
q
3
35 2 1
9:128 10 kg m s Magnitude of the electron spin angular momentum = h
4
34 2 1
1:054 10 kg m s Planck angular momentum = h
12 2 1
3 10 kg m s Rough angular momentum of an arti cial satellite
33 2 1
5:9 10 kg m s Earth rotational angular momentum
41 2 1
1:7 10 kg m s Sun rotational angular momentum
43 2 1
3:1 10 kg m s Total angular momentum of our solar system
55 2 1
2 10 kg m s Angular momentum of the Sun around the center of the Milky Way
66 2 1
4 10 kg m s Rough total angular momentum of the Milky Way
13
1 10 teslas Sp ontaneous human brain activity
12
1 10 teslas Evoked human brain activity
12
1 10 teslas Typical magnetic eld needed for go o d radio reception
11
1 10 teslas Typical magnetic eld from a human heart
10
1 10 teslas Typical 50/60 Hz magnetic eld inside a building
10
5 10 teslas Typical magnetic eld strength in the lo cal interstellar medium
9
1 10 teslas Typical magnetic eld strength in a radio lob e
8
1 10 teslas Typical magnetic eld strength in the central 300 parsecs of the Milky Way
8
5 10 teslas Magnetic eld in the Crab Nebula
7
1 10 teslas Magnetic eld in The Arc at the Milky Way center
6
1 10 teslas Typical magnetic eld from a hand held cordless phone
5
3 10 teslas Magnetic eld at Earth's surface
4
1 10 teslas Magnetic eld near Sun's p ole
4
4 10 teslas Magnetic eld at Jupiter's cloud tops
0:1 teslas Ap star magnetic eld
0:2 teslas Sunsp ot magnetic eld
1 teslas Typical medical NMR magnetic eld
2 teslas Magnetic eld felt by the electron in an n =1 hydrogen atom
2 teslas RS CVn star sp ot magnetic eld
12 teslas Typical magnetic eld used in high resolution NMR sp ectroscopy
25 teslas Powerful sup erconducting/normal hybrid magnet
8
1 10 teslas Typical single pulsar dip ole magnetic eld strength
9
4:4 10 teslas Magnetic eld strength when the energy of the rst electron Landau level is
comparable to the electron rest mass MNRAS 275, 257
4
1 10 amp eres Peak lightning b olt current
6
5 10 amp eres Current along Io's ux tub e Science 262, 1035
8
3 10 volts Typical p otential di erence across a lightning b olt
6 1
3 10 Vm Electrical discharge eld in air with ions
12 1
1 10 Vm Typical electric eld at the surface of a pulsar
19 1
1 10 Vm QED pair pro duction electric eld limit 11
240 bits Eigen replicator genome | 120 nucleotides
440 bits Spiegelman monster genome | 220 nucleotides
9 000 bits Q virus genome | 4 500 nucleotides
32 000 bits Single spaced typ ed page
5
6:6 10 bits Uncompressed ASCI I version of Lysistrata
6
4:36 10 bits C. elegans nemato de chromosome I I I | longest contiguous piece of DNA sequenced
6
6 10 bits E. Coli genome | 3 million nucleotides
6
6:3 10 bits Uncompressed ASCI I version of ATale of Two Cities
7
2:6 10 bits Yeast genome | 13 million nucleotides
7
3:6 10 bits Uncompressed ASCI I version of The Bible
8
2 10 bits Nemato de genome | 100 million nucleotides
9
1 10 bits Micro computer hard drive
9
2:5 10 bits Twentyvolume edition of the Oxford English Dictionary on CD-ROM
9
7 10 bits MACHO pro ject data intake p er night
9
9 10 bits Human genome
10
8 10 bits Sloan Digital Sky Survey sp ectral database
11
1:4 10 bits Cambridge X-ray group total disk space
11
2 10 bits International Halley watch database
11
5 10 bits VCR tap e
12
1 10 bits Sp eed reading for 80 years with p erfect memory
12
8:8 10 bits HST archive size in mid-1994
12
9 10 bits VLA FIRST Survey data set
13
2 10 bits Digitized new Palomar sky survey
13
5 10 bits Sloan Digital Sky Survey 0.4 arcsecond pixel map
13
8 10 bits NSF backb one trac in March 1994
16
3 10 bits HDTV for 80 years with p erfect memory
1
200 bits s Typical reading and talking rate
1
500 bits s Fast sp eed reading rate
1
24 000 bits s Hipparcos satellite data acquisition rate
1
56 000 bits s Typical Internet link
5 1
1 10 bits s High quality audio
5 1
1:4 10 bits s HST archive mean growth rate
7 1
1 10 bits s Xerox Ethernet
7 1
1 10 bits s HDTV bit rate after compression
7 1
4:5 10 bits s Internet backb one T3 link
7 1
6 10 bits s Sloan Digital Sky Survey data acquisition rate
10 1
3 10 bits s Soliton optical b er information transmission rate
15 1
2 10 bits s Sexual repro duction genetic information transmission rate
2 100 1994 USA dollars Average USA public scho ol sp ending p er pupil in 1960
6 200 1994 USA dollars Average USA public scho ol sp ending p er pupil in 1993
5
2 10 1994 USA dollars Vancouver liquid mercury mirror telescop e
6
9 10 1994 USA dollars Income of St. John's College, Cambridge during 1992{1993
7
1:5 10 1994 USA dollars Development and construction cost of the Giant Meterwave Radio Telescop e near
Pune, India
7
2:9 10 1994 USA dollars Total predicted cost of the Sloan Digital Sky Survey
7
3 10 1994 USA dollars Rough United States ACLU yearly national op erations budget
7
3 10 1994 USA dollars Rough United States NRA lobbying budget
7
5:5 10 1994 USA dollars Development, construction, and launch cost of the Clementine I spacecraft
7
8:5 10 1994 USA dollars VLBA development and construction cost
7
9 10 1994 USA dollars Development and construction cost of the Keck telescop e
8
1 10 1994 USA dollars Development and construction cost of the ASCA X-ray satellite
8
1:5 10 1994 USA dollars Typical holdings of an old wealthy Oxbridge college 12
8
1:5 10 1994 USA dollars Rough cost of a Europ ean Ariane ro cket launch
8
2 10 1994 USA dollars Development and construction cost of the VLA
8
2:1 10 1994 USA dollars Total sp ending in the 1994 United States senate election campaigns
8
3:7 10 1994 USA dollars Rough construction and op eration cost for 4 years of LIGO
8
7:8 10 1994 USA dollars Rough United States NEA revenues
8
9 10 1994 USA dollars Development, construction, and launch cost of the Magel lan prob e
8
9:8 10 1994 USA dollars Development, construction, and launch cost of the Mars Observer spacecraft
9
1:1 10 1994 USA dollars Worldwide Visa and MasterCard fraud in 1993
9
1:5 10 1994 USA dollars Planned total cost of the AXAF X-ray mission
9
1:6 10 1994 USA dollars Estimated cost of the CERN Large Hadron Collider
9
1:7 10 1994 USA dollars Barclays 1994 half-year pro ts
9
1:8 10 1994 USA dollars Amount of fo o d stamp fraud in the USA in 1993
9
3:5 10 1994 USA dollars Planned total cost of the Cassini spacecraft
9
3:8 10 1994 USA dollars Microsoft revenue in 1993
10
1 10 1994 USA dollars Rough monetary losses asso ciated with BCCI
10
1:3 10 1994 USA dollars Lo ckheed revenue in 1993
10
1:4 10 1994 USA dollars NASA planned 1995 budget
10
1:5 10 1994 USA dollars Rough United Nations yearly budget
10
2:8 10 1994 USA dollars Planned cost for the space station
10
4:4 10 1994 USA dollars Total cost of the rst 20 B-2 Stealth b omb ers
10
5 10 1994 USA dollars Clinton administration 1995 loan guarantee to Mexico
11
1 10 1994 USA dollars Rough annual gap b etween USA IRS estimates of federal taxes due and tax revenues
actually collected
11
2:6 10 1994 USA dollars United States 1994 military sp ending
11
2:6 10 1994 USA dollars United States 1994 predicted defecit
11
8 10 1994 USA dollars United States 1994 entitlement sp ending e.g. so cial security, medicare, medicaid,
fo o d stamps, unemployment comp ensation, farm aid, federal p ensions
12
1 10 1994 USA dollars Rough total United States health care sp ending in 1994
12
1:3 10 1994 USA dollars United States 1994 tax receipts
12
1:5 10 1994 USA dollars United States 1994 federal government sp ending
12
3:5 10 1994 USA dollars United States antip overty sp ending since 1965
12
4:4 10 1994 USA dollars United States 1994 national debt
12
6:4 10 1994 USA dollars United States 1994 gross domestic pro duct
13
1:4 10 1994 USA dollars United States 1994 unfunded liabilities for so cial security, medicare, federal
civil-service retirement and military retirement
14
3:1 10 1994 USA dollars World 1994 GDP
0:004 Blackvelvet optical light alb edo
0:012 Black cloth optical light alb edo
0:04 Halley's comet optical light alb edo
0:068 Mo on optical light alb edo
0:14 Mars optical light alb edo
0:40 Earth optical light alb edo
0:80 White pap er optical light alb edo
0:85 Venus optical light alb edo
10 3
1 10 pc Space density of X-ray binaries in the Milky Way
7 3
5 10 pc Space density of pulsars in the solar neighborhood
6 3
3 10 pc Space density of cataclysmic variables in the solar neighborhood
3
0:1 pc Space density of main sequence stars in the solar neighborhood
9 3
1 10 Mp c Ultraluminous IRAS galaxies
9 3
1 10 Mp c Quasars
7 3
1 10 Mp c QSOs 13
7 3
1 10 Mp c FR I I radio galaxies edge-brightened
6 3
5 10 Mp c FR I radio galaxies not edge-brightened
4 3
1 10 Mp c Seyfert galaxies
3
0:1 Mp c Field galaxies
3
0:6 Mp c Group galaxies
26:8 V apparent magnitude of the Sun
12:5 V apparent magnitude of the full Mo on
4:4 V apparent magnitude of Venus at its brightest
1:5 V apparent magnitude of Sirius
0:1 V apparent magnitude of the LMC
0:5 V apparent magnitude of Betelgeuse
3:4 V apparent magnitude of M31
6:5 V apparent magnitude of naked eye limit at a dark site
9 V apparent magnitude of 50-mm bino cular limit
10:5 V apparent magnitude of the z =0:00363 Seyfert 2 NGC 1068
11:6 V apparent magnitude of the z =0:00170 H I I region galaxy NGC 5408
12:8 V apparent magnitude of the z =0:158 quasar 3C273
13:6 V apparent magnitude of the z =0:0167 Seyfert 1 NGC 7469
14:5 V apparent magnitude of 12-in telescop e visual limit
15:3 V apparent magnitude of the z =0:239 quasar PG 0953+414 ApJ 435, L12
19:55 V apparent magnitude of the z =3:67 quasar DHM 0054 284
23:5 V apparent magnitude of 200-in telescop e photographic limit
25:5 V apparent magnitude of a typical Cepheid in M100 ApJ 435, L33
29:5 V apparent magnitude limit of an 18-hour exp osure with HST
27:5 M of the z =0:158 quasar 3C273
V
24:1 M of the z =0:239 quasar PG 0953+414 ApJ 435, L12
V
21:1 M of M31
V
21:0 M of a typical Seyfert host galaxy
V
19:5 M limit on the host galaxy of the z =0:239 quasar PG 0953+414 ApJ 435, L12
V
18:5 M of the LMC
V
6:0 M of Betelgeuse
V
4:4 M of the most luminous star in Alpha Centauri
V
4:79 M of the Sun
V
1
Note: I assume an in ationary = 1:0 dust- lled Friedmann-Rob ertson-Walker universe with H = 50 km s
0 0
1 18 1
Mp c =1:62 10 s for all calculations. Space densities are given for \here and now." 14