APPARENT HORIZON

The table lists the distance of the apparent horizon measured along the curved surface of the Earth. I suppose the Earth's globe spherical and I neglected the effect of the atmospheric refraction.

 

 H                D
Heigt of       Distance
the observer
(m)           (km)

 1             3.569
 2             5.047
 3             6.181
 4             7.137
 5             7.98
 6             8.741
 7             9.442
 8             10.093
 9             10.706
 10            11.285
 11            11.836
 12            12.362
 13            12.867
 14            13.352
 15            13.821
 16            14.274
 17            14.714
 18            15.14
 19            15.555
 20            15.959
 21            16.353
 22            16.738
 23            17.114
 24            17.482
 25            17.843
 26            18.196
 27            18.543
 28            18.883
 29            19.217
 30            19.546
 31            19.869
 32            20.187
 33            20.5
 34            20.808
 35            21.112
 36            21.411
 37            21.707
 38            21.998
 39            22.286
 40            22.57
 41            22.85
 42            23.127
 43            23.401
 44            23.671
 45            23.939
 46            24.203
 47            24.465
 48            24.724
 49            24.98
 50            25.234
 51            25.485
 52            25.733
 53            25.98
 54            26.224
 55            26.465
 56            26.705
 57            26.942
 58            27.177
 59            27.411
 60            27.642
 61            27.871
 62            28.099
 63            28.325
 64            28.549
 65            28.771
 66            28.991
 67            29.21
 68            29.427
 69            29.643
 70            29.857
 71            30.069
 72            30.28
 73            30.49
 74            30.698
 75            30.905
 76            31.11
 77            31.314
 78            31.517
 79            31.718
 80            31.918
 81            32.117
 82            32.315
 83            32.511
 84            32.706
 85            32.901
 86            33.094
 87            33.285
 88            33.476
 89            33.666
 90            33.854
 91            34.042
 92            34.228
 93            34.414
 94            34.599
 95            34.782
 96            34.965
 97            35.146
 98            35.327
 99            35.507
 100           35.686
 200           50.467
 300           61.809
 400           71.370
 500           79.793
 600           87.409
 700           94.412
 800           100.93
 900           107.051
 1000          112.841
 1200          123.61
 1400          133.512
 1600          142.729
 1800          151.384
 2000          159.571
 2500          178.4
 3000          195.421
 3500          211.072
 4000          225.638
 4500          239.318
 5000          252.255
 6000          276.313
 7000          298.433
 8000          319.017
 9000          338.347
 10000         356.625