User:Floaterfluss/My projects/Orders of magnitude (time)

Some radioisotopes have extremely long half-lives:
 * 5.4 &times; 10&minus;44 s – the Planck time, the earliest time after the Big Bang that theoretical physics can describe.
 * 0.3 yoctoseconds – mean life of the W and Z bosons.
 * 1 ys, time for top quark decay
 * 91 ys, half-life of lithium-4
 * 7 zs, half-life of helium-9's outer neutron in the second nuclear halo
 * about 17 zs, the approximate period of electromagnetic radiation at the boundary between gamma rays and X-rays
 * about 300 zs, typical cycle time of X-rays, on the boundary between hard and soft X-rays
 * 1 attosecond (1 as) – estimated time it takes for an atomic nucleus to recoil
 * about 100 attoseconds – record for shortest time interval measured as of February 2004 (BBC News)
 * about 200 attoseconds – half-life of beryllium-8, maximum time available for the triple-alpha process for the synthesis of carbon and heavier elements in stars.
 * 250 attoseconds – the shortest pulses of laser light yet created (2002)
 * 320 attoseconds – estimated time it takes electrons to hop between atoms
 * 1.3 femtoseconds (fs) – cycle time for 390 nanometre light, transition from visible light to ultraviolet
 * 2.57 femtoseconds – cycle time for 770 nanometre light, transition from visible light to near-infrared
 * 100 femtoseconds – the time required to travel across a human hair, if travelling at the speed of light
 * 200 femtoseconds – the swiftest chemical reactions, such as the reaction of pigments in an eye to light
 * 300 femtoseconds – the duration of a vibration of the atoms in an iodine molecule
 * 1 picosecond – half-life of a bottom quark
 * 1.66 picoseconds – switching time of the world's fastest transistor (604 GHz, as of 2005) Article
 * 3.3 picoseconds (approximately) – time taken for light to move 1 millimetre
 * 10 picoseconds after the Big Bang – electromagnetism separates from the other fundamental forces
 * 1.087827757 &times; 10&minus;10 seconds – transition time between the two hyperfine levels of the ground state of the caesium-133 atom at zero kelvins
 * 1.0 nanoseconds (1.0 ns) – cycle time for frequency 1 GHz, radio wavelength 0.3 m
 * 1.02 nanoseconds (approximately) – time taken for light to travel 1 foot
 * 3.3 nanoseconds (approximately) – the time it takes a common 3.0 GHz computer CPU to add two integers
 * 3.33564095 nanoseconds (approximately) – time taken for light to travel 1 metre
 * 10 nanoseconds (10 ns) – cycle time for frequency 100 MHz, radio wavelength 3 m (VHF, FM band)
 * 10 nanoseconds – one shake, approximate time of one generation of a nuclear chain reaction with fast neutrons
 * 12 nanoseconds – half-life of a K meson
 * 20–40 nanoseconds – time of fusion reaction in a hydrogen bomb
 * 0.1 microseconds (μs) – cycle time for frequency 10 MHz, radio wavelength 30 m (shortwave)
 * 0.333 microseconds – cycle time of highest medium wave radio frequency, 3 MHz
 * 0.500 microseconds – T1 time of Josephson phase qubit (see also Qubit) as of May 2005
 * 1 microsecond (1 μ s ) – cycle time for frequency 1 MHz, radio wavelength 300 m (AM mediumwave band)
 * 1 microsecond – the length of time of a high-speed, commercial strobe light flash
 * 2 microseconds – the life time of a muonium particle
 * 3.33564095 microseconds – the time taken by light to travel one kilometre in a vacuum
 * 5.4 microseconds – the time taken by light to travel one mile in a vacuum
 * 1 microsecond (1 μ s ) – cycle time for frequency 1 MHz, radio wavelength 300 m (AM mediumwave band)
 * 1 microsecond – the length of time of a high-speed, commercial strobe light flash
 * 2 microseconds – the life time of a muonium particle
 * 3.33564095 microseconds – the time taken by light to travel one kilometre in a vacuum
 * 5.4 microseconds – the time taken by light to travel one mile in a vacuum
 * 0.1 milliseconds (0.1 ms) – cycle time for frequency 10 kHz
 * 0.125 milliseconds – sampling interval for telephone audio (8000 samples/s)
 * 0.24 milliseconds – half-life of ununbium 277
 * 0.25 milliseconds – cycle time for highest tone in telephone audio (4 kHz)
 * 1 millisecond (1 ms) – cycle time for frequency 1 kHz
 * 1 millisecond – duration of light for typical photo flash strobe
 * 1 millisecond – repetition interval of GPS C/A PN code
 * 1.000692286 milliseconds – time taken for light to travel 300 km in a vacuum
 * 2 milliseconds – half life of hassium-265
 * 2.27 milliseconds – cycle time for the A above middle C in music (440 Hz); if a tuning device for musical instruments generates just one tone, it is probably this tone
 * 3 milliseconds – a housefly’s wing flap
 * 3.4 milliseconds – half life of meitnerium-266
 * 5 milliseconds – a honeybee’s wing flap
 * 8 milliseconds – camera shutter speed at setting 125
 * 9 milliseconds – typical maximum seek time for a 7200rpm hard disk
 * 10 milliseconds (10 ms) – cycle time for frequency 100 Hz (also known as a "jiffy")
 * 16.7 milliseconds – cycle time for American 60 Hz AC mains grid
 * 20 milliseconds – cycle time for European 50 Hz AC mains grid
 * 33.3 milliseconds – the amount of time one frame lasts in 30fps video
 * 50 milliseconds – cycle time for the lowest audible tone, 20 Hz
 * 60 milliseconds – cycle time for European 16.7 Hz AC electrified railroad power grid
 * 62.5 milliseconds - a sixty-fourth note at MM = 60
 * 30 to 100 milliseconds – typical minimum latency for a broadband internet connection (important for online gaming)
 * 100 milliseconds (100 ms) – the blink of an eye; see also human's periods
 * 100 milliseconds – the reaction speed of a human
 * 102 milliseconds – half-life of bohrium-262
 * 125 milliseconds - a thirty-second note at MM = 60
 * 134 milliseconds – time taken by light to travel around the earth's equator
 * 150 milliseconds – recommended maximum time delay for telephone service
 * 250 milliseconds – recommended maximum time delay for a computer terminal or web page
 * 250 milliseconds is an approximate average of the round trip time for communications via geosynchronous satellites
 * 250 milliseconds - a sixteenth note at MM = 60
 * 200 to 670 milliseconds – a beat of modern dance music
 * 400 milliseconds - time in which the fastest baseball pitches reach the strike zone
 * 500 milliseconds - an eighth note at MM = 60
 * 838 milliseconds – half-life of lithium-8
 * 100 milliseconds (100 ms) – the blink of an eye; see also human's periods
 * 100 milliseconds – the reaction speed of a human
 * 102 milliseconds – half-life of bohrium-262
 * 125 milliseconds - a thirty-second note at MM = 60
 * 134 milliseconds – time taken by light to travel around the earth's equator
 * 150 milliseconds – recommended maximum time delay for telephone service
 * 250 milliseconds – recommended maximum time delay for a computer terminal or web page
 * 250 milliseconds is an approximate average of the round trip time for communications via geosynchronous satellites
 * 250 milliseconds - a sixteenth note at MM = 60
 * 200 to 670 milliseconds – a beat of modern dance music
 * 400 milliseconds - time in which the fastest baseball pitches reach the strike zone
 * 500 milliseconds - an eighth note at MM = 60
 * 838 milliseconds – half-life of lithium-8
 * 27 seconds – half life of dubnium-261
 * 30 seconds – half life of seaborgium-266
 * 30 seconds – half life of ununquadium-289
 * 30 seconds – most common length of a TV commercial in the USA
 * 32.184 seconds – the amount that Terrestrial Time precedes International Atomic Time
 * 34 seconds – half life of dubnium-262
 * 60 seconds = one minute
 * 61 seconds – half life of rutherfordium-261
 * 86.4 seconds = 1 minute 26.4 seconds = 10-3 days – the length of a Swatch ".beat"
 * 100 seconds = 1 minute 40 seconds
 * 100 seconds – 1 minute 40 seconds, or 1.666... minutes
 * 102 seconds – half-life of nobelium-253
 * 102 seconds – duration of the Minute Waltz of Frédéric Chopin, as recorded by Dinu Lipatti
 * 180 seconds = 3 minutes – approximate time for cooking instant noodles or for boiling an egg
 * 273 seconds – nominal duration of 4'33 by John Cage
 * 315 seconds = 5.25 minutes (approximately 10-5 years) after the Big Bang – first nuclei form
 * 500 seconds = 8.333... minutes – approximate time it takes light to travel between earth and the sun
 * 660 seconds = 11 minutes – duration of a 1000-foot reel of 35mm motion picture film
 * 886 seconds (approximately 14.8 minutes) – half-life of a free neutron
 * 930 seconds (approximately 15.5 minutes), may vary by performance, duration of the Brandenburg Concerto by Johann Sebastian Bach
 * 1000 seconds – approximately 16.7 minutes
 * 1892 seconds = 31'32" - duration of Igor Stravinsky's ballet score Le Sacre du printemps (composer's 1960 recording).
 * 2700 seconds = 45 minutes – the length of the Anglo-Zanzibar War, the shortest war in history
 * 2926 seconds = 48 minutes 46 seconds – the change in time of moon rise from one day to the next
 * 3000 seconds (approximately): duration of Johannes Brahms' second piano concerto
 * 3320 seconds = 56 minutes - duration of the collapse of World Trade Center #2 (South Tower) on September 11, 2001
 * 3480 seconds = 58 minutes – half-life of nobelium-259
 * 3600 seconds = 60 minutes = one hour
 * 4440 seconds = 74 minutes – the originally specified maximum length of audio that can be stored on a 120-mm compact disc
 * 5400 seconds = 90 minutes – the time needed for an object in low earth orbit to circle the earth
 * 5700 seconds = 95 minutes – length of Gustav Mahler's Third Symphony, the longest symphony in the repertory of classical music
 * 7140 seconds = 119 minutes – runtime of the film Citizen Kane
 * 10,379 seconds = 2 hours 52 minutes 59 seconds = the length of the record New York–London Concorde flight
 * 19,872 seconds = 5.52 hours – half-life of mendelevium-257
 * 25,200 seconds = 7 hours – one work day in France.
 * 28,800 seconds = 8 hours – one work day in many Western countries
 * 28,800 seconds = 8 hours – common human daily need for sleep
 * 36,000 seconds = 10 hours – one work day in ancient Egypt, according to the oldest definition of an hour
 * 37,296 seconds = 10.36 hours – half-life of erbium-165
 * 54,000 seconds = 15 hours – approximate length of Wagner's opera cycle Der Ring des Nibelungen
 * 72,606 seconds = 20 hours 10 minutes 6 seconds – the world record of human standing motionlessly as of 2005
 * 80,100 seconds = 22.25 hours – approximate time taken to solve the DES Challenge III of RSA on January 18 - 19, 1999
 * 86,164 seconds = 23 hours 56 minutes 4 seconds – time for Earth’s rotation around its axis
 * 86,400 seconds = 24 hours = one day
 * 91,404 seconds = 25.39 hours – half-life of fermium-252
 * 102,888 seconds = 28.58 hours – half life of erbium-160
 * 259,200 seconds = 3 days – half-life of fermium-253
 * 432,000 seconds = 5 days – one work week
 * 483,062.4 seconds = 5.591 days – half life of manganese-52
 * 604,800 seconds = 7 days = one week
 * 799,200 seconds = 9.25 days – half life of thulium-167
 * 864,000 seconds = 10 days – length of a new week (décade) in the French Revolutionary Calendar
 * 1.21&times;106 seconds = 14 days – a fortnight
 * 1.38&times;106 seconds = 15.9735 days – half life of vanadium-48
 * 1.54&times;106 seconds = 17.81 days – half life of californium-253
 * 2.36&times;106 seconds = 27.3217 days – sidereal month
 * 2.39&times;106 seconds = 27.7025 days – half life of chromium-51
 * 2.42&times;106 seconds = 28 days – length of February in non-leap years
 * 2.51&times;106 seconds = 29 days – length of February in a leap year
 * 2.55&times;106 seconds = 29.53059 days – mean synodic month
 * 2.59&times;106 seconds = 30 days – length of the months April, June, September, and November
 * 2.68&times;106 seconds = 31 days – length of the months January, March, May, July, August, October, and December
 * 4.45&times;106 seconds = 51.5 days – half life of mendelevium-258
 * 5.23&times;106 seconds = 60.5 days – half life of californium-254
 * 6.68&times;106 seconds = 77.27 days – half life of cobalt-56
 * 7.24&times;106 seconds = 83.79 days – half life of scandium-46
 * 7.54&times;106 seconds = 87.32 days – half life of sulfur-35
 * 7.60&times;106 seconds = 87 days 23.3 hours – one orbit of Mercury
 * 7.78&times;106 seconds = 90 days – common length of a product warranty (in the United States)
 * 7.78&times;106 seconds = 90 days – approximate length of a quarter year, a common corporate and financial reporting interval
 * 8.04&times;106 seconds = 93.1 days – half life of thulium-168
 * 8.68&times;106 seconds = 100.5 days – half life of fermium-257
 * 10 megaseconds = 115.74 days
 * 128.6 days &mdash; half life of thulium-170
 * 138 days &mdash; half life of polonium- 210
 * 224.701 days &mdash; one orbit of Venus
 * 271.79 days &mdash; half life of cobalt-57
 * 280 days &mdash; average length of a human pregnancy; ~24 million seconds
 * 330 days &mdash; half life of vanadium-49
 * 333.5 days &mdash; half life of californium-248
 * 353, 354 or 355 days &mdash; the lengths of regular years in some lunisolar calendars
 * 354.37 days &mdash; 12 lunar months; the average length of a year in lunar calendars
 * 365 days &mdash; a regular year in many solar calendars; ~31.53 million seconds
 * 365.24219 days &mdash; a mean tropical year near the year 2000
 * 365.2424 days &mdash; a vernal equinox year.
 * 365.2425 days &mdash; the average length of a year in the Gregorian calendar
 * 365.25 days &mdash; the average length of a year in the Julian calendar
 * 365.2564 days &mdash; a sidereal year
 * 366 days &mdash; a leap year in many solar calendars; 31.62 million seconds
 * 373.59 days &mdash; half-life of ruthenium-106
 * 383, 384 or 385 days &mdash; the lengths of leap years in some lunisolar calendars
 * 383.9 days &mdash; 13 lunar months; leap year in some lunisolar calendars
 * 396.1 days &mdash; half-life of neptunium-235
 * 462.6 days &mdash; half-life of cadmium-109
 * 1.88 years &mdash; one orbit of Mars
 * 1.92 years &mdash; half life of thulium-171
 * 100 megaseconds = 3.2 years
 * 3.3 years – half life of rhodium-101
 * 4 years – full term of the President of the United States
 * 4.6 years – orbital period of Ceres
 * 5.2714 years – half life of cobalt-60
 * 6 years – full term of a Senator in the United States
 * 7 years – the interval between leap seconds on December 31, 1998 and December 31, 2005, the longest one as of 2006
 * 10 years – one decade = 3.16 &times; 108 seconds
 * 11 years – sunspot activity cycle (7.5 to 11 years)
 * 11.87 years – one orbit of Jupiter
 * 13.08 years – half life of californium-250
 * 16.13 years – half life of niobium meta state Nb-93m
 * 18.03 years – Saros cycle, the period of solar eclipses and lunar eclipses
 * 19.0002 years – 235 months (1 Metonic cycle)
 * 29 years – recorded maximum lifespan of a dog
 * 29.1 years – half life of curium-243
 * 29.458 years – one orbit of Saturn
 * 35 years – Constitutionally-mandated minimum age for President of the United States.
 * 50.5 years – average age of human menopause
 * 60 years – duration of Indian independence as of 2007
 * 63 years – half-life of titanium-44
 * 65 years – a common age for retirement of workers
 * 68.9 years – half-life of uranium-232
 * 72 years, 3 months, 18 days: reign of Louis XIV
 * 75 years – average life span of humans in the First World
 * 78 years – estimated maximum lifespan of an elephant
 * 84 years, 3 days, 15.66 hours – one orbit of Uranus
 * 100 years – one century = 3.16 &times; 109 seconds
 * 100.1 years – half-life of nickel-63
 * 122 years and 164 days – longest recorded lifespan of any known human (Jeanne Calment)
 * 130 years – approximate age of the telephone, recorded music, and the electric light
 * 165 years – one orbit of Neptune
 * 190 years – credited age of the oldest known tortoise, oldest land animal
 * 231 years – age of the United States of America as of 2007
 * 247.7 years – one orbit of Pluto
 * 269 years – half-life of argon-39
 * 288 years – one orbit of Quaoar
 * 292 years – age of the ruling Hanoverian dynasty (1714) in Great Britain as of 2006
 * 302 years – duration of Spanish colonial rule in Mexico
 * 304 years – duration of the Romanov dynasty in Russia
 * 351 years – half-life of californium-249
 * 377 years – age (in 2007) of the Massachussetts General Court, oldest continuous extant elected assembly
 * 403 years – duration of the Hohenzollern monarchy in Brandenburg, Prussia, and Germany
 * 418 years – half life of silver-108
 * 432.2 years – half life of americium-241
 * 507 years – duration of the Roman Empire
 * 515 years – time since Christopher Columbus reached the New World
 * 555 years – oldest surviving printing by movable type
 * 680 years – half life of niobium-91
 * 685 years (approximately) – age of Dante Aligheri's Divine Comedy
 * 790 years – approximate duration of Zhou Dynasty (c.1046 BC - 256 BC), the longest dynasty in Chinese history.
 * 898 years – half life of californium-251
 * 1000 years – one millennium = 3.16 x 1010 seconds*
 * 1053 years – duration of the Byzantine Empire
 * 1140 years – age of Varangian settlements and influence in Russia
 * 1427 years – time since the Hegira
 * 1550 years (approximately) – time since the Anglo-Saxon invasion of Britain
 * 1927 years – time since the volcanic destruction of Pompeii (79AD)
 * 2439 years – age of the Parthenon as a completed building (432 BC)
 * 2500 years (approximately) age of Euclid's Elements
 * 2782 years – time since the legendary founding of Rome (776 BC)
 * 3,200 years – time since the Greek Dark Ages and the beginning of the Iron Age
 * 3,800 years – time since alphabetic writing emerged
 * 4,500 years – approximate time since the domestication of the horse
 * 4,700 years – estimated age of oldest living plant, a bristle-cone pine
 * 5,300 years – time since Sumerians developed cuneiform writing
 * 5,400 years – time since Neolithic Age ended and Bronze Age began
 * 5,715 years – half-life of Carbon-14
 * 6,010 years – age of the earth according to the calculation of Bishop Ussher (in 2006)
 * 6,500 years [3500 in the Dutch version of Wikipedia] – time since the invention of the wheel
 * 7,370 years – half life of americium-243
 * 8,500 years – half life of curium-245
 * 10,000 years – time since city of Jericho was founded
 * 10,000 years – time since end of Pleistocene Epoch
 * 10,000 years – time since beginning of Holocene Epoch
 * 12,000 years – time since beginning of Neolithic Age
 * 12,000 years – time since the land ice left Denmark and southern Sweden
 * 20,000 years – approximate age of the Ishango Bone, the oldest known tally stick
 * 20,300 years – half life of niobium-94
 * 21,000 years – time since the Last Glacial Maximum
 * 24,110 years – half life of plutonium-239
 * 25,000 years – time since the first colonisation of North America
 * 30,000 years – approximate age of Haplogroup X (mtDNA) and Haplogroup I (mtDNA)
 * 40 000 years – time since the Cro-Magnon colonisation of Europe (Upper Paleolithic)
 * 50 000 years – age of Haplogroup B (mtDNA)
 * 60 000 years – approximate age of Haplogroup N (mtDNA), Haplogroup C (mtDNA) and Haplogroup A (mtDNA); out of Africa migration.
 * 75 000 years – time since the ancestors of the Indigenous Australians reached Australia
 * 76 000 years – half-life of nickel-59
 * 80 000 years – approximate age of Haplogroup M (mtDNA)
 * 90 000 years – approximate age of Y-chromosomal Adam
 * 100 000 years – earliest estimate for the domestication of dogs
 * 150 000 years – approximate age of mitochondrial Eve
 * 154 000 years – half-life of neptunium-236
 * 159 200 years – half-life of uranium-233
 * 160 000 years – time since the Homo sapiens idaltu/Homo sapiens sapiens split
 * 200 000 years – approximate age of Homo sapiens
 * 211 100 years – half-life of technetium-99
 * 250 000 years – approximate age of Homo neanderthalensis
 * 300 000 years – time since Homo sapiens separated from Homo erectus (Middle Paleolithic)
 * 301,000 years – half-life of chlorine-36
 * 340,000 years – half-life of curium-248
 * 379 000 years – time after the Big Bang until cosmic microwave background radiation began
 * 500 000 years – time since the colonisation of Eurasia by Homo erectus
 * ~700,000 years – time since last reversal of earth's magnetic field
 * 790 000 years – age of the earliest evidence of the controlled use of fire by Homo erectus
 * 1,000,000 years – the average lifespan of a blue supergiant star
 * 1,500,000 years – time since beginning of Pleistocene Epoch (beginning of Quaternary Period)
 * 1,500,000 years – time since end of Pliocene Epoch (end of Tertiary Period)
 * 1,530,000 years – half-life of zirconium-93
 * 2,000,000 years – duration of the Paleolithic
 * 2,500,000 years – approximate age of the genus Homo
 * 2,600,000 years – half-life of technetium-97
 * 3.74 million years – half-life of manganese-53
 * 4 million years – estimated average lifetime of biological species
 * 4 million years – time since beginning of last ice age
 * 4.2 million years – half-life of technetium-98
 * 4.5 million years – approximate age of the genus Australopithecus
 * 5 million years – time since beginning of Pliocene Epoch
 * 5 million years – time since end of Miocene
 * 5.5 million years – approximate age of the genus Ardipithecus
 * 5-7 million years – estimated age of the Pan/Homo split
 * 6.5 million years – half-life of palladium-107
 * 15.6 million years – half-life of curium-247
 * 18-12 million years – estimated age of the Hominidae family
 * 20 million years – time since the first forms of grass appeared
 * 23.42 million years – half-life of uranium-236
 * 24 million years – time since beginning of Miocene Epoch
 * 24 million years – time since end of Oligocene Epoch
 * 34.7 million years – half-life of niobium-92
 * 36 million years – time since end of Eocene Epoch and beginning of Oligocene Epoch; age of the Cercopithecidae (Old World primates) superfamily.
 * 40 million years – estimated period of time until Australia will collide with Asia; time since the age of the Catarrhini parvorder.
 * 65 million years – time since Cretaceous-Tertiary extinction event at end of Cretaceous Period (end of Mesozoic Era) and beginning of Tertiary Period (beginning of Cenozoic Era); age of the Haplorrhini suborder.
 * 135 million years – time since end of Jurassic and beginning of Cretaceous Period.
 * 195 million years – time since end of Triassic and beginning of Jurassic Period; time since the appearance of the earliest mammals.
 * 225 million years – time since end of Permian Period (end of Palaeozoic Era) and beginning of Triassic Period (beginning of Mesozoic Era).
 * 250 million years – Galactic year - a revolution around the center of the Milky way of our Sun and the Solar system.
 * 280 million years – time since end of Carboniferous and beginning of Permian Period.
 * 340 million years&mdash;time since the beginning of the Carboniferous and the end of Devonian period
 * 400 million years&mdash;time since the beginning of the Devonian and the end of the Silurian period
 * 420 million years&mdash;time since the first creature took a breath of air
 * 435 million years&mdash;time since the beginning of the Silurian and the end of the Ordovician period
 * 500 million years&mdash;time since the beginning of the Ordovician and the end of the Cambrian period
 * 540 million years&mdash;time since the beginning of the Cambrian and the end of the Precambrian period. Time since the Cambrian explosion and age of the earliest Vertebrates.
 * 575 million years&mdash; age of the oldest Animal fossils
 * 580 million years&mdash;time since the end of a possible Snowball Earth ice age
 * 600 million years&mdash;age of first complex multicelled lifeforms
 * 703.8 million years&mdash;half-life of uranium-235
 * 750 million years&mdash;time since the beginning of a possible Snowball Earth ice age
 * 1277 million years&mdash;half-life of potassium-40
 * 1.8-2.1 billion years&mdash;age of the earliest Eukaryotes
 * 2.3 billion years&mdash;time since the first known ice age
 * 3.0 billion years&mdash;time until the potential collision between the Milky Way and Andromeda galaxies
 * 3.5 billion years &mdash; age of oldest cellular life (Prokaryotes)
 * 3.7 to 3.9 billion (3.7e9 to 3.9e9) years &mdash; age of the Mare Imbrium, the Lower Imbrian epoch
 * 4.468 billion years &mdash; half-life of uranium-238
 * 4.5 billion years &mdash; age of the Earth (see: Precambrian)
 * 10 billion years &mdash; expected main sequence lifetime of a G2 dwarf star (like the Sun)
 * 13.7 ± 0.2 billion years (4e17 seconds) &mdash; estimated age of the universe according to the Big Bang theory
 * 20 billion years &mdash; time until the end of the universe in the Big Rip scenario
 * 100 billion (1011) years – If the Universe is closed, the estimated total lifetime of the Universe
 * 3.3 &times; 1012 years – According to the traditional Vedic time of Hinduism, this is the lifetime of Brahma.
 * (1.4 &plusmn; 0.4) &times; 1017 years – vanadium-50
 * (1.9 &plusmn; 0.2) &times; 1019 years – bismuth-209
 * (3.1 &plusmn; 0.4) &times; 1019 years – cadmium-116
 * (2.2 &plusmn; 0.3) &times; 1024 years – tellurium-128

The following times all assume that the Universe is "open":


 * 1014 years – the estimated time until low-mass stars cool off. The smallest red dwarf stars are the longest-lived stars, and are believed to have a lifetime of up to 14 trillion years (1.4 x 1013 years). Star formation is expected to cease in galaxies in about 1013 to 1014 years as galaxies are depleted of the gas clouds they need to form stars. The longest-lived stars formed from the last gas clouds will therefore cool off after about 2 x 1014 years.
 * 1015 years – the estimated time until planets detach from stars. Whenever two stars pass close to each other, the orbits of the planets can be disrupted and the planets can be ejected from orbit around their parent star. Planets that orbit closer to their stars take longer to be ejected in this manner on average because a passing star must make a closer pass to the planet's star to eject the planet.
 * 1019 years – the estimated time until stars detach from galaxies. When two stars pass close enough to each other, the stars exchange orbital energy with lower-mass stars tending to gain energy. The lower-mass stars can gain enough energy in this manner through repeated encounters to be ejected from the galaxy. This process can cause the galaxy to eject the majority of its stars.
 * 1020 years – the estimated time until orbits decay by gravitational radiation
 * 1030 years – the estimated time until galaxies disappear due to black holes
 * 1036 years – the estimated half-life for proton decay, if GUT is right
 * 1040 years – the estimated expiration of all protons in the universe due to proton decay, if GUT is right (probability dictates only less than one proton in the universe will survive its half-life if its true value is close to the theoretical lower bound)
 * 1045 years – the estimated half-life of theorized radioactive decay of protons by virtual black holes, if they exist
 * 1064 years – the estimated time until black holes decay by the Hawking process
 * 1065 years – the estimated timescale at which all matter is liquid at zero temperature due to tunneling effects
 * 10100 years (a googol year) – the estimated time until supermassive black holes decay by the Hawking process
 * 101500 years – the estimated time until all matter decays to iron (if the proton does not decay)
 * $$10^{10^{26}}$$ years – low estimate for the time until all matter collapses into black holes, assuming no proton decay
 * $$10^{10^{76}}$$ years – high estimate for the time until all matter collapses into neutron stars or black holes, again assuming no proton decay. Dyson, Freeman: Reviews of Modern Physics, Vol. 51, No. 3, July 1979(c) 1979 American Physical Society
 * This time assumes a statistical model subject to Poincaré recurrence. A much simplified way of thinking about this time is in a model where our universe's history repeats itself arbitrarily many times due to properties of statistical mechanics, this is the time scale when it will first be somewhat similar (for a reasonable choice of "similar") to its current state again.


 * $$10^{10^{10^{10^{10^{1.1}}}}}$$ years – scale of an estimated Poincaré recurrence time for the quantum state of a hypothetical box containing a black hole with the estimated mass of our entire universe.