is defined as (see www.physics.sfasu.edu).

Graphical conversion

Table conversion

Conversion of absolute magnitude to diameter (in km) H [mag] albedo 0.50 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.5 1493 1574 1669 1784 1927 2111 2361 2726 3338 4721 1.0 1186 1250 1326 1417 1531 1677 1875 2165 2652 3750 1.5 942.0 992.9 1053 1126 1216 1332 1489 1720 2106 2979 2.0 748.2 788.7 836.6 894.3 966.0 1058 1183 1366 1673 2366 2.5 594.3 626.5 664.5 710.4 767.3 840.5 939.7 1085 1329 1879 3.0 472.1 497.6 527.8 564.3 609.5 667.7 746.5 861.9 1056 1493 3.5 375.0 395.3 419.3 448.2 484.1 530.3 592.9 684.7 838.5 1186 4.0 297.9 314.0 333.0 356.0 384.6 421.3 471.0 543.9 666.1 942.0 4.5 236.6 249.4 264.5 282.8 305.5 334.6 374.1 432.0 529.1 748.2 5.0 187.9 198.1 210.1 224.6 242.6 265.8 297.2 343.1 420.3 594.3 5.5 149.3 157.4 166.9 178.4 192.7 211.1 236.1 272.6 333.8 472.1 6.0 118.6 125.0 132.6 141.7 153.1 167.7 187.5 216.5 265.2 375.0 6.5 94.20 99.29 105.3 112.6 121.6 133.2 148.9 172.0 210.6 297.9 7.0 74.82 78.87 83.66 89.43 96.60 105.8 118.3 136.6 167.3 236.6 7.5 59.43 62.65 66.45 71.04 76.73 84.05 93.97 108.5 132.9 187.9 8.0 47.21 49.76 52.78 56.43 60.95 66.77 74.65 86.19 105.6 149.3 8.5 37.50 39.53 41.93 44.82 48.41 53.03 59.29 68.47 83.85 118.6 9.0 29.79 31.40 33.30 35.60 38.46 42.13 47.10 54.39 66.61 94.20 9.5 23.66 24.94 26.45 28.28 30.55 33.46 37.41 43.20 52.91 74.82 10.0 18.79 19.81 21.01 22.46 24.26 26.58 29.72 34.31 42.03 59.43 10.5 14.93 15.74 16.69 17.84 19.27 21.11 23.61 27.26 33.38 47.21 11.0 11.86 12.50 13.26 14.17 15.31 16.77 18.75 21.65 26.52 37.50 11.5 9.420 9.929 10.53 11.26 12.16 13.32 14.89 17.20 21.06 29.79 12.0 7.482 7.887 8.366 8.943 9.660 10.58 11.83 13.66 16.73 23.66 12.5 5.943 6.265 6.645 7.104 7.673 8.405 9.397 10.85 13.29 18.79 13.0 4.721 4.976 5.278 5.643 6.095 6.677 7.465 8.619 10.56 14.93 13.5 3.750 3.953 4.193 4.482 4.841 5.303 5.929 6.847 8.385 11.86 14.0 2.979 3.140 3.330 3.560 3.846 4.213 4.710 5.439 6.661 9.420 14.5 2.366 2.494 2.645 2.828 3.055 3.346 3.741 4.320 5.291 7.482 15.0 1.879 1.981 2.101 2.246 2.426 2.658 2.972 3.431 4.203 5.943 15.5 1.493 1.574 1.669 1.784 1.927 2.111 2.361 2.726 3.338 4.721 16.0 1.186 1.250 1.326 1.417 1.531 1.677 1.875 2.165 2.652 3.750 16.5 0.942 0.993 1.053 1.126 1.216 1.332 1.489 1.720 2.106 2.979 17.0 0.748 0.789 0.837 0.894 0.966 1.058 1.183 1.366 1.673 2.366 17.5 0.594 0.626 0.664 0.710 0.767 0.841 0.940 1.085 1.329 1.879 18.0 0.472 0.498 0.528 0.564 0.609 0.668 0.746 0.862 1.056 1.493 18.5 0.375 0.395 0.419 0.448 0.484 0.530 0.593 0.685 0.839 1.186 19.0 0.298 0.314 0.333 0.356 0.385 0.421 0.471 0.544 0.666 0.942 19.5 0.237 0.249 0.265 0.283 0.305 0.335 0.374 0.432 0.529 0.748 20.0 0.188 0.198 0.210 0.225 0.243 0.266 0.297 0.343 0.420 0.594 20.5 0.149 0.157 0.167 0.178 0.193 0.211 0.236 0.273 0.334 0.472 21.0 0.119 0.125 0.133 0.142 0.153 0.168 0.188 0.217 0.265 0.375 21.5 0.094 0.099 0.105 0.113 0.122 0.133 0.149 0.172 0.211 0.298 22.0 0.075 0.079 0.084 0.089 0.097 0.106 0.118 0.137 0.167 0.237 22.5 0.059 0.063 0.066 0.071 0.077 0.084 0.094 0.109 0.133 0.188 23.0 0.047 0.050 0.053 0.056 0.061 0.067 0.075 0.086 0.106 0.149 23.5 0.038 0.040 0.042 0.045 0.048 0.053 0.059 0.068 0.084 0.119 24.0 0.030 0.031 0.033 0.036 0.038 0.042 0.047 0.054 0.067 0.094 24.5 0.024 0.025 0.026 0.028 0.031 0.033 0.037 0.043 0.053 0.075 25.0 0.019 0.020 0.021 0.022 0.024 0.027 0.030 0.034 0.042 0.059 25.5 0.015 0.016 0.017 0.018 0.019 0.021 0.024 0.027 0.033 0.047 26.0 0.012 0.013 0.013 0.014 0.015 0.017 0.019 0.022 0.027 0.038 26.5 0.009 0.010 0.011 0.011 0.012 0.013 0.015 0.017 0.021 0.030 27.0 0.007 0.008 0.008 0.009 0.010 0.011 0.012 0.014 0.017 0.024 27.5 0.006 0.006 0.007 0.007 0.008 0.008 0.009 0.011 0.013 0.019 28.0 0.005 0.005 0.005 0.006 0.006 0.007 0.007 0.009 0.011 0.015 28.5 0.004 0.004 0.004 0.004 0.005 0.005 0.006 0.007 0.008 0.012 29.0 0.003 0.003 0.003 0.004 0.004 0.004 0.005 0.005 0.007 0.009 29.5 0.002 0.002 0.003 0.003 0.003 0.003 0.004 0.004 0.005 0.007 30.0 0.002 0.002 0.002 0.002 0.002 0.003 0.003 0.003 0.004 0.006 30.5 0.001 0.002 0.002 0.002 0.002 0.002 0.002 0.003 0.003 0.005 31.0 0.001 0.001 0.001 0.001 0.002 0.002 0.002 0.002 0.003 0.004 0.50 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 H [mag] albedo