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Contents |
Seconds
| Factor (s) | Multiple | Symbol | Definition | Comparative examples & common units | Orders of magnitude |
|---|---|---|---|---|---|
| 10−44 | tP | Planck time is the unit of time of the natural units system known as Planck units.[1] | The shortest or earliest meaningful interval of time that theoretical physics can describe and consequently the youngest the known universe can be measured. ≈ 5.4×10−44 s. | 10−44 s | |
| 10−24 | 1 yoctosecond | ys[2] | Yoctosecond, (yocto + second), is one quadrillionth (in the long scale) or one septillionth (in the short scale) of a second. | 0.3 ys: mean life of the W and Z bosons.citation needed 1 ys: time for top quark decay.citation needed 91 ys: half-life of lithium-4.citation needed |
1 ys and less, 10 ys, 100 ys |
| 10−21 | 1 zeptosecond | zs | Zeptosecond, (zepto + second), is one trillionth of one billionth of one second. | 7 zs: half-life of helium-9's outer neutron in the second nuclear halo. 17 zs: approximate period of electromagnetic radiation at the boundary between gamma rays and X-rays. 300 zs: approximate typical cycle time of X-rays, on the boundary between hard and soft X-rays |
1 zs, 10 zs, 100 zs |
| 10−18 | 1 attosecond | as | 100 attoseconds: shortest measured period of time.[3][4] | 1 as, 10 as, 100 as | |
| 10−15 | 1 femtosecond | fs | cycle time for 390 nanometre light, transition from visible light to ultraviolet | 1 fs, 10 fs, 100 fs | |
| 10−12 | 1 picosecond | ps | 1 ps: half-life of a bottom quark 4 ps: Time to execute one machine cycle by an IBM Silicon-Germanium transistor (supercomputer) |
1 ps, 10 ps, 100 ps | |
| 10−9 | 1 nanosecond | ns | 1 ns: Time to execute one machine cycle by an Intel Pentium 4 1GHz microprocessor 1 ns: Light travels 12 inches (30 cm) 1,000,000,000 nanoseconds: 1 second |
1 ns, 10 ns, 100 ns | |
| 10−6 | 1 microsecond | µs | sometimes also abbreviated µsec 1 µs: Time to execute one machine cycle by an Intel 80186 microprocessor |
1 µs, 10 µs, 100 µs | |
| 10−3 | 1 millisecond | ms | 2 ms: Time to execute one machine cycle by a minicomputer 50-80 ms: Blink of an eye 150-300 ms: Human reflex response to visual stimuli |
1 ms, 10 ms, 100 ms | |
| 100 | 1 second | s | 60 s: 1 minute | 1 s, 10 s, 100 s | |
| 103 | 1 kilosecond (16.7 minutes) |
ks | 3.6 ks: 3600 s or 1 hour 86.4 ks: 86 400 s or 1 day 604.8 ks: 1 week |
103 s, 104 s, 105 s | |
| 106 | 1 megasecond (11.6 days) |
Ms | month = 2.6 x 106 s year = 31.6 Ms = 107.50 s ≈ π x 107 s |
106 s, 107 s, 108 s | |
| 109 | 1 gigasecond (32 years) |
Gs | century = 3.16 Gs ≈ π×109 s millennium = 31.6 Gs ≈ π×1010 s |
109 s, 1010 s, 1011 s | |
| 1012 | 1 terasecond (32 000 years) |
Ts | eon = 31.6 Ts ≈ π×1013 s | 1012 s, 1013 s, 1014 s | |
| 1015 | 1 petasecond (32 million years) |
Ps | aeon = 31.6 Ps ≈ π×1016 s 4.3×1017 s ≈ 13.7 billion years, the approximate age of the universe |
1015 s, 1016 s, 1017 s | |
| 1018 | 1 exasecond (32 billion years) |
Es | 1018 s, 1019 s, 1020 s | ||
| 1021 | 1 zettasecond (32 trillion years) |
Zs | 1021 s, 1022 s, 1023 s | ||
| 1024 | 1 yottasecond (32 quadrillion years) |
Ys | 1024 s, 1025 s, 1026 s and more |
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Years
| Factor (a) | Multiple | common units | orders of magnitude |
|---|---|---|---|
| 10−50 | Planck time, the shortest physically meaningful interval of time ≈ 1.71×10−50 a | 10−50 a | |
| 10−24 | 1 yoctoannum | -- | 1 ya and less, 10 ya, 100 ya |
| 10−21 | 1 zeptoannum | -- | 1 za, 10 za, 100 za |
| 10−18 | 1 attoannum | -- | 1 aa, 10 aa, 100 aa |
| 10−15 | 1 femtoannum | -- | 1 fa, 10 fa, 100 fa |
| 10−12 | 1 picoannum | -- | 1 pa, 10 pa, 100 pa |
| 10−9 | 1 nanoannum | 1 second = 3.17 × 10-8 a ≈ 10-7.50 a | 1 na, 10 na, 100 na |
| 10−6 | 1 microannum | 1 minute = 1.90 × 10-6 a 1 hour = 1.40 × 10-4 a |
1 ua, 10 ua, 100 ua |
| 10−3 | 1 milliannum | 1 day = 2.73 × 10-3 a 1 week = 1.91 × 10-2 a |
1 ma, 10 ma, 100 ma |
| 100 | 1 annum | year = 1 annum decade = 10 anna century = 100 anna |
1 a, 10 a, 100 a |
| 103 | 1 kiloannum | millennium = 1000 anna | 103 a, 104 a, 105 a |
| 106 | 1 megaannum | epoch = 1,000,000 anna | 106 a, 107 a, 108 a |
| 109 | 1 gigaannum | aeon = 1,000,000,000 anna 1.37×1010 a ≈ 13.7 billion years, the approximate age of the universe |
109 a, 1010 a, 1011 a |
| 1012 | 1 teraannum | --- | 1012 a, 1013 a, 1014 a |
| 1015 | 1 petaannum | --- | 1015 a, 1016 a, 1017 a |
| 1018 | 1 exaannum | -- | 1018 a, 1019 a, 1020 a |
| 1021 | 1 zettaannum | -- | 1021 a, 1022 a, 1023 a |
| 1024 | 1 yottaannum | -- | 1024 a, 1025 a, 1026 and more |
The pages linked in the right-hand column contain lists of times that are of the same order of magnitude (power of ten). Rows in the table represent increasing powers of a thousand (3 orders of magnitude).
Conversion from year to second is year × 31 557 600 using the Julian year. Conversion from log10 year to log10 second is approximately log10 year + 7.50. Example conversion; 1 year = 100 year = 100 + 7.50 seconds = 100.50 + 7s = 3.16 * 107s.
See also
- Natural history
- Geologic timescale
- Human timescales
- Logarithmic timeline
- Timeline of evolution
- Timeline of the Big Bang
External links
- Exploring Time from Planck time to the lifespan of the universe
Footnotes
- ^ Wikipedia contributors. Planck time. Wikipedia, The Free Encyclopedia. December 7, 2007, 05:55 UTC. Available at: http://en.wikipedia.org/w/index.php?title=Planck_time&oldid=176315682. Accessed December 19, 2007.
- ^ The American Heritage Dictionary of the English Language: Fourth Edition. 2000. Available at: http://www.bartleby.com/61/21/Y0022100.html. Accessed December 19, 2007. note: abbr. ys or ysec
- ^ "Shortest time interval measured". BBC News (25 February 2004).
- ^ "Fastest view of molecular motion". BBC News (4 March 2006).
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