time

an SI Tour℠

Latest revision: 15 September 2014.

Note on half lives. The data for half lives in this tour come from an online database maintained for many years by R. B. Firestone at Lawrence Berkeley Lab and L.P. Ekström at Lund University. The links on the isotopes, however, are to a web site created by J. Nilsson who, using the most current web tools, brought the data into the 21st century web. The data, however, are still those of the LBNL site.

time in
yoctoseconds
(10−24)
 
between 0.16 and 0.6 Lifetime of the top quark, shortest lifetime of any form of matter.

The CDF Collaboration, a team so large that we are forced to abandon our usual practice of naming all authors.
A direct measurement of the total decay width of the top quark.
arXiv:1308.4050v2 [hep=ex] October 21, 2013.

? Ipp et al proposed a way of making pulses of light only a few yoctoseconds long, emitted by a quark-gluon plasma.

Physical Review Letters
doi:10.1103/PhysRevLett.103.152301

300 Mean neutron-proton equilibration time of dynamically deformed atomic nuclei created in collisions of two zinc-70 nuclei.

A. Jedele, A. B. McIntosh, K. Hagel, M. Huang, L. Heilborn, Z. Kohley, L. W. May, E. McCleskey, M. Youngs, A. Zarrella, and S. J. Yennello.
Characterizing neutron-proton equilibration in nuclear reactions with subzeptosecond resolution.
Physical Review Letters, vol 118, issue 6, 062501 (10 February 2017)
doi:10.1103/PhysRevLett.118.062501

time in
zeptoseconds
(10−21)
 
   
   
   
time in
attoseconds
(10−18)
 
20 Delay before electron struck by a UV photon jumps to new orbit.
  A ~6 femtosecond movie (containing 40 frames) of a krypton ion's outermost electron.

Eleftherios Goulielmakis, Zhi-Heng Loh, Adrian Wirth, Robin Santra, Nina Rohringer, Vladislav S. Yakovlev, Sergey Zherebtsov, Thomas Pfeifer, Abdallah M. Azzeer, Matthias F. Kling, Stephen R. Leone & Ferenc Krausz.
Real-time observation of valence electron motion.
Nature, vol 466, pages 739–743 (05 August 2010)
doi:10.1038/nature09212

time in
femtoseconds
(10−15)
 
229 Interval between frames of STAMP, a sort of high-speed motion picture camera. This value corresponds to a rate of 4,370,000,000 frames per second.

K. Nakagawa, A. Iwasaki, Y. Oishi, R. Horisaki, A. Tsukamoto, A. Nakamura, K. Hirosawa, H. Liao, T. Ushida, K. Goda, F. Kannari and I. Sakuma.
Sequentially timed all-optical mapping photography (STAMP).
Nature Photonics, published online 10 August 2014.
doi:10.1038/nphoton.2014.163

time in
picoseconds
(10−12)
 
37 Half life of the radioactive isotope 236mPu (a nuclear isomer of plutonium-236).
40 Half life of the radioactive isotope 242mCm (a nuclear isomer of curium-242).
<200 Half life of the radioactive isotope 16B (boron-16)
600 Half life of the radioactive isotope 238mPu (a nuclear isomer of plutonium-238)
690 Half life of the radioactive isotope 214mRn (a nuclear isomer of radon-214)
time in
nanoseconds
(10−9)
 
>1 Half life of the radioactive isotope 238m2U (a nuclear isomer of uranium-238)
2 Half life of the radioactive isotope 245mBk (a nuclear isomer of berkelium-245)
2.6 Half life of the radioactive isotope 239m2Pu (a nuclear isomer of plutonium-239)
3 Half life of the radioactive isotope 234mPu (a nuclear isomer of plutonium-234)
3.5 Half life of the radioactive isotope 215mFr (a nuclear isomer of francium-215)
5 Half life of the radioactive isotope 243mBk (a nuclear isomer of berkelium-243)
5 Half life of the radioactive isotope 237mAm (a nuclear isomer of americium-237)
6 Half life of the radioactive isotope 238m2Pu (a nuclear isomer of plutonium-238)
6.5 Half life of the radioactive isotope 214m2Rn (a nuclear isomer of radon-214)
9.5 Half life of the radioactive isotope 242mBk (a nuclear isomer of berkelium-242)
<20 Half life of the radioactive isotope 30Ar (argon-30)
20 Firing of 176 lasers at the National Ignition Facility to compress diamond to 5 terapascals. 

Ray F. Smith, J. H. Eggert, R. Jeanloz, T. S. Duffy, D. G. Braun, J. R. Patterson, R. E. Rudd, J. Biener, A. E. Lazicki, A. V. Hamza, J. Wang, T. Braun, L. X. Benedict, P. M. Celliers and G. W. Collins.
Ramp compression of diamond to five terapascals.
Nature (letter), vol. 511, issue 7509, pages 330–333 (17 July 2014).
doi:10.1038/nature13526

53 Half life of the radioactive isotope 219Pa (protactinium-219)
69 Half life of the radioactive isotope 217Ac (actinium-217)
86 Half life of the radioactive isotope 215Fr (francium-215)
109 Half life of the radioactive isotope 218Th (thorium-218)
125 Half life of the radioactive isotope 213At (astatine-213)
182 Half life of the radioactive isotope 216Ra (radium-216)
270 Half life of the radioactive isotope 214Rn (radon-214)
299 Half life of the radioactive isotope 212Po (polonium-212)
370 Half life of the radioactive isotope 161Re (rhenium-161)
558 Half life of the radioactive isotope 214At (astatine-214)
600 Half life of the radioactive isotope 110Xe (xenon-110)
700 Half life of the radioactive isotope 216Fr (francium-216)
time in
microseconds
(10−6)
 
1 Half life of the radioactive isotope 222U (uranium-222)
11.8 Half life of the radioactive isotope 219Ac (actinium-219)
17 Half life of the radioactive isotope 113Cs (cesium-113)
18 Half life of the radioactive isotope 223U (uranium-223)
22 Half life of the radioactive isotope 217Fr (francium-217)
25.6 Half life of the radioactive isotope 218Ra (radium-218)
42 Half life of the radioactive isotope 219U (uranium-219)
44 Half life of the radioactive isotope 185Bi (bismuth-185)
45 Half life of the radioactive isotope 216Rn (radon-216)
50 Transmission of signal across human synapse.
60 Half life of the radioactive isotope 106Te (tellurium-106)
100 Half life of the radioactive isotope 109I (iodine-109)
227 Time between successive frames of the high speed STAMP camera.

K. Nakagawa, A. Iwasaki, Y. Oishi, R. Horisaki, A. Tsukamoto, A. Nakamura, K. Hirosawa, H. Liao, T. Ushida, K. Goda, F. Kannari and I. Sakuma.
Sequentially timed all-optical mapping photography (STAMP).
Nature Photonics, vol. 8, no. 9, pages 695-700 (September 2014).
doi:10.1038/nphoton.2014.16

444 Half life of the radioactive isotope 156mHf (a nuclear isomer of hafnium-156)
500 Half life of the radioactive isotope 112Cs (cesium-112)
370 Half life of the radioactive isotope 258Fm (fermium-258
900 Half life of the radioactive isotope 158W (tungsten-158)
time in
milliseconds
(10−3)
 
1 Half life of the radioactive isotope 203Ra (radium-203)
   
300 Blink of a human eye
time in
seconds
 
10.62 Women's 100-meter record, set by Florence Griffith-Joyner, 1988 Seoul Olympics.
19.30 Men's 200-meter record, set by Usain Bolt, 2008 Beijing Olympics.
21.34 Women's 200-meter record, set by Florence Griffith-Joyner, 1988 Seoul Olympics.
43.49 Men's 400-meter record, set by Michael Johnson, 1996 Atlanta Olympics.
492 Time for light to travel from the sun to the Earth.
878.5
± 0.7[statistical]
± 0.3[systematic]
Lifetime of a free neutron, as determined by the “bottle” method (2005).

Anatoli P. Serebrov.
Neutron lifetime measurements using gravitationally trapped ultracold neutrons.
Physics-Uspekhi, vol 48, no. 9, pages 867–885 (2005).
doi: 10.1070/PU2005v048n09ABEH003536

880.0 ± 0.9 Mean lifetime of a free neutron.

J. Beringer et al. (Particle Data Group), Phys. Rev. D86, 010001 (2012)
and 2013 partial update for the 2014 edition. (http://pdg.lbl.gov)

886.3
± 1.2[statistical]
± 3.2 [systematic]
Lifetime of a free neutron, as determined by the “beam” method (2005).

J. S. Nico, M. S. Dewey, D. M. Gilliam, F. E. Wietfeldt, X. Fei, W. M. Snow, G. L. Greene, J. Pauwels, R. Eykens, A. Lamberty, J. Van Gestel, and R. D. Scott.
Measurement of the neutron lifetime by counting trapped protons in a cold neutron beam.
Physical Review C, vol 71, page 055502 (25 May 2005).
doi: http://dx.doi.org/10.1103/PhysRevC.71.055502

887.7
± 1.2[statistical]
± 1.9 [systematic]
Lifetime of a free neutron, as determined by the “beam” method (2013).

A. T. Yue, M. S. Dewey, D. M. Gilliam, G. L. Greene, A. B. Laptev, J. S. Nico, W. M. Snow, and F. E. Wietfeldt.
Improved determination of the neutron lifetime.
Physical Review Letters, vol 111, 222501 (November 2013).
doi: http://dx.doi.org/10.1103/PhysRevLett.111.222501

time inbr> kiloseconds
(103)
 
1.381 World record for holding the breath underwater, set by Goran Čolak on 20 June 2014 at Vir in Croatia.
2.6448 Men's steeplechase record, set by Julius Kariuki, 1988 Seoul Olympics.
   
5.772 Orbital period of the first artificial satellite, Sputnik 1, launched by the U.S.S.R. in 1957.
86.4 A 24-hour day, clock time.
951.84 Period of time 17-year-old Randy Gardner went without sleep in 1964. He was observed by a doctor and a sleep researcher.
time in
megaseconds
(106)
 
2.194556 Rotational period of the sun.
31.557 Length of the tropical year on Earth.
31.558 Length of the sidereal year on Earth.
~139 Brooding period observed for an octopus (Graneledone boreopacifica) off the coast of California.

Bruce Robison, Brad Seibel and Jeffrey Drazen.
Deep-Sea Octopus (Graneledone boreopacifica) conducts the longest-known egg-brooding period of any animal.
PLoS One 9(7): e103437 (30 July 2014)
doi:10.1371/journal.pone.0103437

Great video: www.youtube.com/watch?feature=player_embedded&v=lFCQltYMLQk

Ming's shell

Ming

Courtesy Bangor University

time in
gigaseconds
(109)
 
~3.156 A century.
3.864 196 Lifespan of Jeanne Louise Calment (21 February 1875 – 4 August 1997), 122 years and 164 days.
3.951 Half-life of polonium-209.

R. Collé, R. P. Fitzgerald and L. Laureano–Perez.
A new determination of the 209Po half-life.
Journal of Physics G: Nuclear and Particle Physics, vol 41, no. 10 (2014).
doi:10.1088/0954-3899/41/10/105103

~8 Alleged lifespan of Adwaita, a male Aldabra Tortoise (Dipsochelys dussumieri) that died in 2006 in the Kolkata Zoo. His birth year had been estimated by what was known of his history as a pet of Sir Robert Clive. At the time of Adwaita's death, plans to radiocarbon date his shell were announced, but we have been unable to locate any published record of such dating.
16 Lifespan of an Ocean quahog (Arctica islandica) named Ming, determined to be 507 years by counting annual growth increments in its shell. They named it Ming because it was born during the Ming Dynasty in China.

Paul G. Butler, Alan D. Wanamaker, James D. Scourse, Christopher A. Richardson and David J. Reynolds.
Variability of marine climate on the North Icelandic Shelf in a 1357-year proxy archive based on growth increments in the bivalve Arctica islandica.
Palaeogeography, Palaeoclimatology, Palaeoecology, vol 373, pages 141-151 (1 March 2013).

~31.56 A millenium.
159.8 Age (in 2014) of the oldest known bristlecone pine (Pinus longaeva) in California's White Mountains. (5064 years and counting. Its location and identity is a secret.)

http://www.rmtrr.org/oldlist.htm

~514 A “year” on the planet GU Psc b.

Marie-Eve Naud, Étienne Artigau, Lison Malo, Loïc Albert, René Doyon, David Lafrenière, Jonathan Gagné, Didier Saumon, Caroline V. Morley, France Allard, Derek Homeier, Charles A. Beichman, Christopher R. Gelino and Anne Boucher.
Discovery of a wide planetary-mass companion to the young M3 star GU Psc.
The Astrophysical Journal, vol. 787, no. 1, page 5 (28 April 2014).
doi:10.1088/0004-637X/787/1/5

820.5 The Earth wobbles on its axis like a top. Over this period of time, its axis traces out a complete cone, whose center line is perpendicular to the plane of Earth's orbit. The phenomenon is called precession.
time in
teraseconds
(1012)
 
1.29 The tilt of Earth's axis relative to the plane of its orbit varies from 22.1 degrees to 24 degrees and back again over this period of time.
139 Age of zircon from the Jack Hills in Western Australia.

John W. Valley, Aaron J. Cavosie, Takayuki Ushikubo, David A. Reinhard, Daniel F. Lawrence, David J. Larson, Peter H. Clifton, Thomas F. Kelly, Simon A. Wilde, Desmond E. Moser and Michael J. Spicuzza.
Hadean age for a post-magma-ocean zircon confirmed by atom-probe tomography.
Nature Geoscience (letter), vol 7, pages 219–223 (February 2014).
doi:10.1038/ngeo2075

397.4 Age of the solar system.
time in
petaseconds
(1015)
 
1.19 Age of the universe.
   
time in
exaseconds
(1018)
 
1.19 Half life of the isotope 176Lu (lutetium-176)
time in
zettaseconds
(1021)
 
at least 31.5 Half life of the radioactive isotope 180mTa (a nuclear isomer of tantalum-180)
time in
yottaseconds
(1024)
 
69,400,000 Half life of the isotope 128Te (tellurium-128)
>14,500,000,000 Mean life of electron. “This is the best limit for the mode eνγ. The best limit for ‘electron disappearance’ is 6.4 × 1024 yr.”

J. Beringer et al. (Particle Data Group), Physical Review D86, 010001 (2012) and 2013 partial update for the 2014 edition (http://pdg.lbl.gov)

6,620,000,000,000 Mean life of proton, “for p → anything or ‘disappearance’ modes of a bound proton.”

J. Beringer et al. (Particle Data Group), Physical Review D86, 010001 (2012) and 2013 partial update for the 2014 edition (http://pdg.lbl.gov)

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