TT(BIPM97) is a realization of Terrestrial Time as defined by Recommendation IV of Resolution A4 of the International Astronomical Union, adopted at its XXIst General Assembly (1991). The scale unit of TT(BIPM97) is chosen to agree with the SI second on the rotating geoid and its origin is defined by the following relation to TAI : TT(BIPM97) = TAI + 32.184 s on 1977 January 1st, 0 h TAI. TT(BIPM97) has been established according to the principles described in (Guinot B., Atomic time scales for pulsar studies and other demanding applications, Astron. Astrophys., 192, 1988, pp. 370-373), using data from all available primary frequency standards. Following Recommendation S2 (1996) of the CCDS, a frequency correction for the black-body radiation shift has been applied to all primary frequency standard results. The difference TT(BIPM97)-TT(BIPM96) is less than 5 ns until MJD = 48259 (January 3, 1991). Then it increases with an approximate rate of 0.9 ns/d. The largest discrepancy between TT(BIPM97) and TT(BIPM96) is 1355 ns for MJD = 50139 (February 26, 1996). 1st column : MJD at 0 h UTC 2nd " : TT(BIPM97) - EAL - 32.184 s, unit is one microsecond 3rd " : TT(BIPM97) - TAI - 32.184 s, unit is one microsecond 42589. 46.258 46.258 42599. 45.439 45.439 42609. 44.617 44.617 42619. 43.792 43.792 42629. 42.964 42.964 42639. 42.132 42.132 42649. 41.297 41.297 42659. 40.458 40.458 42669. 39.614 39.614 42679. 38.765 38.765 42689. 37.912 37.912 42699. 37.053 37.053 42709. 36.188 36.188 42719. 35.311 35.311 42729. 34.428 34.428 42739. 33.541 33.541 42749. 32.651 32.651 42759. 31.759 31.759 42769. 30.865 30.865 42779. 29.970 29.970 42789. 29.075 29.075 42799. 28.182 28.182 42809. 27.293 27.293 42819. 26.407 26.407 42829. 25.528 25.528 42839. 24.658 24.658 42849. 23.796 23.796 42859. 22.941 22.941 42869. 22.095 22.095 42879. 21.257 21.257 42889. 20.428 20.428 42899. 19.618 19.618 42909. 18.819 18.819 42919. 18.028 18.028 42929. 17.244 17.244 42939. 16.466 16.466 42949. 15.692 15.692 42959. 14.922 14.922 42969. 14.155 14.155 42979. 13.389 13.389 42989. 12.622 12.622 42999. 11.854 11.854 43009. 11.082 11.082 43019. 10.305 10.305 43029. 9.514 9.514 43039. 8.718 8.718 43049. 7.915 7.915 43059. 7.107 7.107 43069. 6.292 6.292 43079. 5.471 5.471 43089. 4.636 4.636 43099. 3.795 3.795 43109. 2.952 2.952 43119. 2.107 2.107 43129. 1.263 1.263 43139. 0.420 0.420 43149. -0.420 0.012 43159. -1.255 0.041 43169. -2.083 0.077 43179. -2.904 0.120 43189. -3.716 0.172 43199. -4.517 0.235 43209. -5.296 0.320 43219. -6.062 0.418 43229. -6.817 0.527 43239. -7.560 0.648 43249. -8.292 0.780 43259. -9.013 0.923 43269. -9.718 1.065 43279. -10.413 1.216 43289. -11.101 1.376 43299. -11.781 1.542 43309. -12.455 1.715 43319. -13.124 1.892 43329. -13.790 2.056 43339. -14.453 2.222 43349. -15.115 2.390 43359. -15.776 2.558 43369. -16.439 2.725 43379. -17.103 2.890 43389. -17.776 3.029 43399. -18.451 3.166 43409. -19.131 3.299 43419. -19.814 3.427 43429. -20.502 3.551 43439. -21.195 3.671 43449. -21.895 3.765 43459. -22.601 3.855 43469. -23.311 3.940 43479. -24.025 4.020 43489. -24.744 4.096 43499. -25.468 4.167 43509. -26.200 4.231 43519. -26.934 4.290 43529. -27.672 4.348 43539. -28.412 4.403 43549. -29.153 4.456 43559. -29.895 4.510 43569. -30.638 4.561 43579. -31.380 4.614 43589. -32.120 4.669 43599. -32.857 4.727 43609. -33.589 4.790 43619. -34.316 4.858 43629. -35.032 4.937 43639. -35.739 5.025 43649. -36.439 5.119 43659. -37.132 5.221 43669. -37.819 5.330 43679. -38.498 5.445 43689. -39.167 5.570 43699. -39.825 5.708 43709. -40.477 5.851 43719. -41.123 5.999 43729. -41.766 6.152 43739. -42.405 6.307 43749. -43.042 6.465 43759. -43.676 6.626 43769. -44.311 6.786 43779. -44.947 6.945 43789. -45.585 7.102 43799. -46.227 7.255 43809. -46.874 7.403 43819. -47.534 7.521 43829. -48.200 7.632 43839. -48.872 7.737 43849. -49.551 7.836 43859. -50.236 7.928 43869. -50.928 8.014 43879. -51.630 8.089 43889. -52.338 8.159 43899. -53.052 8.223 43909. -53.769 8.283 43919. -54.490 8.340 43929. -55.213 8.394 43939. -55.940 8.445 43949. -56.668 8.495 43959. -57.395 8.545 43969. -58.121 8.597 43979. -58.845 8.650 43989. -59.566 8.707 43999. -60.280 8.771 44009. -60.989 8.839 44019. -61.693 8.913 44029. -62.391 8.993 44039. -63.083 9.079 44049. -63.768 9.171 44059. -64.439 9.260 44069. -65.103 9.356 44079. -65.762 9.458 44089. -66.415 9.566 44099. -67.063 9.678 44109. -67.707 9.794 44119. -68.343 9.901 44129. -68.977 10.010 44139. -69.610 10.120 44149. -70.243 10.230 44159. -70.878 10.338 44169. -71.516 10.443 44179. -72.160 10.524 44189. -72.810 10.600 44199. -73.466 10.670 44209. -74.130 10.732 44219. -74.802 10.786 44229. -75.484 10.829 44239. -76.186 10.853 44249. -76.899 10.866 44259. -77.621 10.870 44269. -78.353 10.864 44279. -79.093 10.850 44289. -79.841 10.827 44299. -80.602 10.792 44309. -81.372 10.748 44319. -82.146 10.699 44329. -82.923 10.648 44339. -83.702 10.595 44349. -84.479 10.543 44359. -85.254 10.495 44369. -86.020 10.454 44379. -86.782 10.418 44389. -87.538 10.387 44399. -88.289 10.363 44409. -89.032 10.346 44419. -89.767 10.337 44429. -90.483 10.345 44439. -91.192 10.362 44449. -91.893 10.387 44459. -92.587 10.419 44469. -93.275 10.457 44479. -93.957 10.501 44489. -94.628 10.556 44499. -95.295 10.614 44509. -95.960 10.674 44519. -96.625 10.736 44529. -97.291 10.796 44539. -97.959 10.854 44549. -98.635 10.903 44559. -99.317 10.947 44569.-100.003 10.986 44579.-100.696 11.019 44589.-101.396 11.045 44599.-102.104 11.063 44609.-102.829 11.064 44619.-103.561 11.057 44629.-104.300 11.044 44639.-105.045 11.025 44649.-105.795 11.001 44659.-106.548 10.973 44669.-107.309 10.938 44679.-108.071 10.901 44689.-108.834 10.865 44699.-109.595 10.830 44709.-110.353 10.797 44719.-111.106 10.770 44729.-111.847 10.754 44739.-112.582 10.745 44749.-113.309 10.744 44759.-114.029 10.750 44769.-114.741 10.764 44779.-115.444 10.787 44789.-116.128 10.828 44799.-116.804 10.878 44809.-117.473 10.935 44819.-118.136 10.997 44829.-118.795 11.064 44839.-119.450 11.135 44849.-120.102 11.209 44859.-120.753 11.284 44869.-121.404 11.358 44879.-122.057 11.431 44889.-122.713 11.501 44899.-123.373 11.566 44909.-124.046 11.620 44919.-124.726 11.665 44929.-125.413 11.704 44939.-126.106 11.736 44949.-126.805 11.763 44959.-127.510 11.784 44969.-128.226 11.794 44979.-128.950 11.795 44989.-129.679 11.792 44999.-130.411 11.786 45009.-131.145 11.778 45019.-131.879 11.769 45029.-132.612 11.762 45039.-133.343 11.757 45049.-134.071 11.755 45059.-134.795 11.757 45069.-135.514 11.763 45079.-136.227 11.777 45089.-136.930 11.799 45099.-137.617 11.820 45109.-138.298 11.848 45119.-138.971 11.884 45129.-139.637 11.926 45139.-140.297 11.974 45149.-140.951 12.029 45159.-141.596 12.075 45169.-142.236 12.126 45179.-142.873 12.181 45189.-143.507 12.237 45199.-144.140 12.295 45209.-144.773 12.354 45219.-145.409 12.392 45229.-146.046 12.429 45239.-146.685 12.463 45249.-147.328 12.495 45259.-147.975 12.522 45269.-148.627 12.544 45279.-149.290 12.554 45289.-149.959 12.559 45299.-150.633 12.559 45309.-151.312 12.554 45319.-151.996 12.545 45329.-152.683 12.531 45339.-153.378 12.510 45349.-154.075 12.487 45359.-154.775 12.461 45369.-155.476 12.433 45379.-156.179 12.405 45389.-156.881 12.377 45399.-157.581 12.351 45409.-158.280 12.326 45419.-158.977 12.303 45429.-159.671 12.283 45439.-160.361 12.266 45449.-161.048 12.254 45459.-161.725 12.250 45469.-162.399 12.250 45479.-163.067 12.256 45489.-163.731 12.266 45499.-164.390 12.281 45509.-165.044 12.300 45519.-165.690 12.329 45529.-166.331 12.361 45539.-166.969 12.397 45549.-167.605 12.435 45559.-168.239 12.475 45569.-168.872 12.516 45579.-169.505 12.557 45589.-170.139 12.597 45599.-170.773 12.637 45609.-171.409 12.675 45619.-172.046 12.712 45629.-172.686 12.746 45639.-173.331 12.775 45649.-173.981 12.799 45659.-174.633 12.820 45669.-175.289 12.839 45679.-175.947 12.854 45689.-176.609 12.866 45699.-177.275 12.874 45709.-177.946 12.877 45719.-178.620 12.877 45729.-179.296 12.875 45739.-179.973 12.872 45749.-180.651 12.868 45759.-181.330 12.863 45769.-182.008 12.876 45779.-182.686 12.889 45789.-183.363 12.904 45799.-184.039 12.919 45809.-184.713 12.936 45819.-185.386 12.954 45829.-186.053 12.978 45839.-186.719 13.003 45849.-187.382 13.031 45859.-188.043 13.061 45869.-188.703 13.093 45879.-189.360 13.127 45889.-190.013 13.165 45899.-190.665 13.205 45909.-191.315 13.245 45919.-191.965 13.287 45929.-192.613 13.330 45939.-193.261 13.373 45949.-193.908 13.417 45959.-194.556 13.461 45969.-195.203 13.505 45979.-195.852 13.547 45989.-196.501 13.589 45999.-197.152 13.629 46009.-197.806 13.666 46019.-198.462 13.701 46029.-199.120 13.735 46039.-199.780 13.766 46049.-200.441 13.796 46059.-201.104 13.824 46069.-201.771 13.849 46079.-202.440 13.871 46089.-203.109 13.893 46099.-203.780 13.913 46109.-204.452 13.933 46119.-205.124 13.952 46129.-205.796 13.971 46139.-206.468 13.990 46149.-207.140 14.009 46159.-207.812 14.029 46169.-208.483 14.049 46179.-209.154 14.070 46189.-209.822 14.092 46199.-210.489 14.116 46209.-211.156 14.141 46219.-211.822 14.166 46229.-212.487 14.192 46239.-213.151 14.219 46249.-213.814 14.248 46259.-214.475 14.277 46269.-215.137 14.307 46279.-215.798 14.337 46289.-216.460 14.366 46299.-217.123 14.395 46309.-217.786 14.422 46319.-218.451 14.449 46329.-219.117 14.474 46339.-219.785 14.497 46349.-220.454 14.519 46359.-221.125 14.540 46369.-221.799 14.557 46379.-222.476 14.571 46389.-223.156 14.583 46399.-223.837 14.592 46409.-224.520 14.600 46419.-225.206 14.606 46429.-225.892 14.611 46439.-226.582 14.612 46449.-227.273 14.613 46459.-227.965 14.612 46469.-228.657 14.610 46479.-229.350 14.609 46489.-230.044 14.607 46499.-230.737 14.605 46509.-231.429 14.604 46519.-232.121 14.603 46529.-232.812 14.604 46539.-233.501 14.605 46549.-234.188 14.609 46559.-234.872 14.616 46569.-235.554 14.625 46579.-236.234 14.637 46589.-236.912 14.650 46599.-237.588 14.666 46609.-238.261 14.683 46619.-238.931 14.705 46629.-239.598 14.729 46639.-240.264 14.754 46649.-240.929 14.781 46659.-241.592 14.809 46669.-242.255 14.837 46679.-242.917 14.866 46689.-243.578 14.896 46699.-244.240 14.925 46709.-244.903 14.954 46719.-245.567 14.981 46729.-246.231 15.008 46739.-246.900 15.030 46749.-247.570 15.051 46759.-248.242 15.071 46769.-248.916 15.088 46779.-249.591 15.104 46789.-250.268 15.118 46799.-250.949 15.129 46809.-251.631 15.137 46819.-252.315 15.145 46829.-252.999 15.152 46839.-253.683 15.159 46849.-254.368 15.165 46859.-255.052 15.172 46869.-255.736 15.180 46879.-256.419 15.188 46889.-257.101 15.198 46899.-257.781 15.208 46909.-258.459 15.221 46919.-259.134 15.239 46929.-259.806 15.259 46939.-260.477 15.281 46949.-261.145 15.305 46959.-261.812 15.330 46969.-262.477 15.357 46979.-263.139 15.388 46989.-263.800 15.419 46999.-264.459 15.452 47009.-265.118 15.485 47019.-265.776 15.520 47029.-266.434 15.554 47039.-267.091 15.589 47049.-267.750 15.623 47059.-268.408 15.657 47069.-269.067 15.691 47079.-269.726 15.724 47089.-270.386 15.756 47099.-271.047 15.787 47109.-271.711 15.815 47119.-272.376 15.843 47129.-273.041 15.870 47139.-273.708 15.896 47149.-274.375 15.921 47159.-275.043 15.945 47169.-275.712 15.967 47179.-276.382 15.988 47189.-277.052 16.009 47199.-277.723 16.030 47209.-278.393 16.051 47219.-279.063 16.071 47229.-279.734 16.092 47239.-280.403 16.114 47249.-281.072 16.136 47259.-281.741 16.159 47269.-282.408 16.183 47279.-283.074 16.208 47289.-283.738 16.235 47299.-284.401 16.264 47309.-285.062 16.294 47319.-285.721 16.325 47329.-286.380 16.358 47339.-287.036 16.393 47349.-287.690 16.431 47359.-288.342 16.470 47369.-288.993 16.510 47379.-289.643 16.551 47389.-290.292 16.593 47399.-290.941 16.636 47409.-291.588 16.679 47419.-292.236 16.723 47429.-292.884 16.766 47439.-293.532 16.810 47449.-294.180 16.852 47459.-294.830 16.894 47469.-295.482 16.933 47479.-296.135 16.971 47489.-296.789 17.009 47499.-297.444 17.045 47509.-298.100 17.079 47519.-298.758 17.113 47529.-299.419 17.143 47539.-300.080 17.173 47549.-300.742 17.202 47559.-301.405 17.231 47569.-302.067 17.259 47579.-302.730 17.288 47589.-303.391 17.319 47599.-304.051 17.350 47609.-304.710 17.382 47619.-305.368 17.415 47629.-306.024 17.450 47639.-306.678 17.487 47649.-307.328 17.528 47659.-307.976 17.571 47669.-308.623 17.616 47679.-309.267 17.663 47689.-309.910 17.711 47699.-310.551 17.761 47709.-311.190 17.810 47719.-311.827 17.859 47729.-312.463 17.910 47739.-313.099 17.961 47749.-313.734 18.013 47759.-314.369 18.065 47769.-315.004 18.116 47779.-315.642 18.166 47789.-316.280 18.215 47799.-316.918 18.263 47809.-317.557 18.311 47819.-318.197 18.358 47829.-318.837 18.404 47839.-319.480 18.449 47849.-320.123 18.492 47859.-320.767 18.536 47869.-321.411 18.579 47879.-322.055 18.621 47889.-322.699 18.664 47899.-323.343 18.703 47909.-323.986 18.742 47919.-324.629 18.782 47929.-325.271 18.822 47939.-325.913 18.863 47949.-326.555 18.904 47959.-327.194 18.942 47969.-327.833 18.982 47979.-328.472 19.021 47989.-329.110 19.061 47999.-329.748 19.102 48009.-330.385 19.143 48019.-331.023 19.179 48029.-331.660 19.216 48039.-332.297 19.253 48049.-332.934 19.290 48059.-333.570 19.327 48069.-334.207 19.364 48079.-334.845 19.396 48089.-335.482 19.428 48099.-336.120 19.460 48109.-336.757 19.493 48119.-337.394 19.525 48129.-338.031 19.558 48139.-338.668 19.586 48149.-339.304 19.615 48159.-339.940 19.645 48169.-340.576 19.674 48179.-341.211 19.705 48189.-341.845 19.736 48199.-342.478 19.768 48209.-343.111 19.800 48219.-343.743 19.834 48229.-344.374 19.868 48239.-345.004 19.904 48249.-345.633 19.940 48259.-346.260 19.977 48269.-346.887 20.016 48279.-347.513 20.055 48289.-348.138 20.096 48299.-348.762 20.137 48309.-349.386 20.179 48319.-350.008 20.215 48329.-350.631 20.251 48339.-351.252 20.289 48349.-351.873 20.327 48359.-352.493 20.365 48369.-353.112 20.405 48379.-353.731 20.438 48389.-354.349 20.473 48399.-354.966 20.507 48409.-355.583 20.543 48419.-356.200 20.578 48429.-356.816 20.614 48439.-357.432 20.651 48449.-358.048 20.688 48459.-358.663 20.724 48469.-359.279 20.761 48479.-359.894 20.798 48489.-360.510 20.835 48499.-361.126 20.871 48509.-361.742 20.903 48519.-362.359 20.934 48529.-362.976 20.965 48539.-363.593 20.996 48549.-364.211 21.026 48559.-364.830 21.055 48569.-365.451 21.078 48579.-366.072 21.101 48589.-366.694 21.123 48599.-367.316 21.144 48609.-367.939 21.165 48619.-368.563 21.185 48629.-369.188 21.203 48639.-369.813 21.222 48649.-370.438 21.240 48659.-371.064 21.258 48669.-371.689 21.277 48679.-372.314 21.296 48689.-372.937 21.316 48699.-373.560 21.337 48709.-374.182 21.358 48719.-374.803 21.381 48729.-375.423 21.405 48739.-376.042 21.429 48749.-376.658 21.452 48759.-377.274 21.476 48769.-377.888 21.501 48779.-378.501 21.527 48789.-379.114 21.554 48799.-379.726 21.582 48809.-380.336 21.606 48819.-380.947 21.631 48829.-381.556 21.656 48839.-382.166 21.681 48849.-382.776 21.706 48859.-383.387 21.731 48869.-383.998 21.755 48879.-384.610 21.777 48889.-385.223 21.800 48899.-385.837 21.821 48909.-386.451 21.842 48919.-387.066 21.862 48929.-387.682 21.881 48939.-388.300 21.898 48949.-388.918 21.915 48959.-389.536 21.932 48969.-390.156 21.947 48979.-390.776 21.962 48989.-391.396 21.977 48999.-392.017 21.991 49009.-392.639 22.005 49019.-393.260 22.018 49029.-393.882 22.031 49039.-394.504 22.044 49049.-395.126 22.057 49059.-395.748 22.070 49069.-396.370 22.083 49079.-396.992 22.096 49089.-397.614 22.109 49099.-398.236 22.122 49109.-398.858 22.140 49119.-399.480 22.158 49129.-400.101 22.176 49139.-400.722 22.194 49149.-401.344 22.212 49159.-401.965 22.230 49169.-402.585 22.249 49179.-403.205 22.268 49189.-403.825 22.288 49199.-404.445 22.307 49209.-405.065 22.327 49219.-405.685 22.346 49229.-406.304 22.366 49239.-406.924 22.386 49249.-407.543 22.406 49259.-408.163 22.426 49269.-408.783 22.445 49279.-409.403 22.465 49289.-410.023 22.484 49299.-410.644 22.502 49309.-411.265 22.521 49319.-411.886 22.539 49329.-412.508 22.556 49339.-413.130 22.574 49349.-413.752 22.591 49359.-414.375 22.607 49369.-414.998 22.623 49379.-415.622 22.639 49389.-416.245 22.655 49399.-416.869 22.671 49409.-417.492 22.686 49419.-418.116 22.702 49429.-418.739 22.718 49439.-419.362 22.735 49449.-419.985 22.751 49459.-420.608 22.768 49469.-421.231 22.784 49479.-421.852 22.802 49489.-422.474 22.820 49499.-423.095 22.838 49509.-423.716 22.856 49519.-424.337 22.875 49529.-424.958 22.893 49539.-425.578 22.912 49549.-426.199 22.931 49559.-426.819 22.950 49569.-427.440 22.969 49579.-428.061 22.987 49589.-428.681 23.006 49599.-429.303 23.024 49609.-429.924 23.042 49619.-430.546 23.059 49629.-431.168 23.077 49639.-431.790 23.094 49649.-432.412 23.111 49659.-433.035 23.128 49669.-433.657 23.145 49679.-434.280 23.162 49689.-434.902 23.179 49699.-435.525 23.195 49709.-436.147 23.213 49719.-436.769 23.230 49729.-437.391 23.248 49739.-438.012 23.266 49749.-438.633 23.284 49759.-439.254 23.302 49769.-439.874 23.321 49779.-440.494 23.340 49789.-441.113 23.359 49799.-441.732 23.379 49809.-442.351 23.399 49819.-442.969 23.419 49829.-443.587 23.440 49839.-444.204 23.460 49849.-444.822 23.480 49859.-445.439 23.501 49869.-446.056 23.522 49879.-446.673 23.542 49889.-447.289 23.563 49899.-447.906 23.583 49909.-448.523 23.603 49919.-449.140 23.623 49929.-449.757 23.642 49939.-450.375 23.662 49949.-450.992 23.681 49959.-451.610 23.700 49969.-452.229 23.717 49979.-452.847 23.735 49989.-453.466 23.752 49999.-454.084 23.769 50009.-454.703 23.787 50019.-455.322 23.804 50029.-455.941 23.820 50039.-456.559 23.836 50049.-457.178 23.852 50059.-457.797 23.869 50069.-458.415 23.886 50079.-459.033 23.903 50089.-459.650 23.920 50099.-460.267 23.937 50109.-460.883 23.955 50119.-461.499 23.973 50129.-462.115 23.992 50139.-462.730 24.011 50149.-463.344 24.030 50159.-463.958 24.049 50169.-464.571 24.069 50179.-465.184 24.089 50189.-465.797 24.110 50199.-466.409 24.131 50209.-467.021 24.152 50219.-467.633 24.173 50229.-468.244 24.194 50239.-468.855 24.215 50249.-469.466 24.237 50259.-470.076 24.259 50269.-470.687 24.280 50279.-471.297 24.302 50289.-471.908 24.323 50299.-472.518 24.344 50309.-473.128 24.366 50319.-473.738 24.387 50329.-474.348 24.408 50339.-474.957 24.429 50349.-475.567 24.450 50359.-476.177 24.470 50369.-476.786 24.492 50379.-477.395 24.513 50389.-478.003 24.534 50399.-478.611 24.555 50409.-479.219 24.576 50419.-479.827 24.597 50429.-480.434 24.619 50439.-481.041 24.641 50449.-481.648 24.663 50459.-482.254 24.684 50469.-482.861 24.705 50479.-483.466 24.727 50489.-484.072 24.749 50499.-484.677 24.772