Ground track for UDA34A3 = UW8551D = WT1190F

The following is based on all 2015 data received as of 31 October. The uncertainty is itself uncertain, since leftover rocket bodies have non-gravitational forces that are not entirely predictable. But it should be good to within a dozen kilometers or so.

The speed is in km/s, relative to the nominal impact point. You'll notice the rather sudden decrease at about 6:19:00 UTC, as the object plows into the atmosphere. (In computing the object's trajectory from its observations, I had to figure out how much solar radiation pressure was pushing it around; that gives you the "AMR", or area/mass ratio. By a lucky coincidence, that's exactly the parameter that tells you how much the object will decelerate at a given altitude and velocity.)

However, that area/mass ratio is only roughly determined. It could easily be wrong by a factor of two. The drag follows standard formulae that involve a coefficient of drag, which is a function of an object's shape. I'm using Cd=0.47, the drag coefficient of a sphere. But the object probably has some other shape.

The following ephemeris also assumes the object will remain intact. In reality, the object will presumably break into bits and pieces about then, which will have a higher level of atmospheric drag. So they'll take a bit longer to flutter down, probably mostly as bits too small to notice. I'm rather hoping somebody on Sri Lanka points a video camera at the object, on a tripod, so that positions can be measured and the object's actual deceleration can be computed.

Date (UT)  HH:MM:SS    lon      lat      alt (km)   svel
---- -- -- --------   -------- -------- ----------  -----
2015 11 13 06:10:00    46.6890 +11.7199   2607.795  8.899
2015 11 13 06:10:10    47.1348 +11.6675   2551.844  8.928
2015 11 13 06:10:20    47.5866 +11.6135   2496.027  8.958
2015 11 13 06:10:30    48.0444 +11.5580   2440.352  8.989
2015 11 13 06:10:40    48.5084 +11.5009   2384.824  9.019
2015 11 13 06:10:50    48.9786 +11.4422   2329.449  9.050
2015 11 13 06:11:00    49.4551 +11.3818   2274.233  9.080
2015 11 13 06:11:10    49.9380 +11.3197   2219.183  9.112
2015 11 13 06:11:20    50.4275 +11.2559   2164.305  9.143
2015 11 13 06:11:30    50.9236 +11.1903   2109.607  9.174
2015 11 13 06:11:40    51.4264 +11.1229   2055.095  9.206
2015 11 13 06:11:50    51.9360 +11.0536   2000.777  9.238
2015 11 13 06:12:00    52.4525 +10.9823   1946.660  9.270
2015 11 13 06:12:10    52.9761 +10.9092   1892.751  9.302
2015 11 13 06:12:20    53.5067 +10.8339   1839.059  9.335
2015 11 13 06:12:30    54.0446 +10.7567   1785.593  9.367
2015 11 13 06:12:40    54.5899 +10.6773   1732.359  9.400
2015 11 13 06:12:50    55.1425 +10.5957   1679.367  9.433
2015 11 13 06:13:00    55.7027 +10.5119   1626.625  9.466
2015 11 13 06:13:10    56.2705 +10.4259   1574.143  9.500
2015 11 13 06:13:20    56.8460 +10.3375   1521.931  9.533
2015 11 13 06:13:30    57.4294 +10.2468   1469.997  9.567
2015 11 13 06:13:40    58.0207 +10.1536   1418.351  9.601
2015 11 13 06:13:50    58.6201 +10.0580   1367.004  9.635
2015 11 13 06:14:00    59.2276 +09.9598   1315.966  9.669
2015 11 13 06:14:10    59.8434 +09.8591   1265.247  9.703
2015 11 13 06:14:20    60.4675 +09.7557   1214.859  9.738
2015 11 13 06:14:30    61.1001 +09.6496   1164.813  9.772
2015 11 13 06:14:40    61.7412 +09.5408   1115.120  9.807
2015 11 13 06:14:50    62.3909 +09.4291   1065.792  9.842
2015 11 13 06:15:00    63.0494 +09.3146   1016.841  9.877
2015 11 13 06:15:10    63.7167 +09.1972    968.279  9.912
2015 11 13 06:15:20    64.3929 +09.0768    920.120  9.947
2015 11 13 06:15:30    65.0782 +08.9533    872.375  9.982
2015 11 13 06:15:40    65.7725 +08.8268    825.059  10.02
2015 11 13 06:15:50    66.4760 +08.6972    778.185  10.05
2015 11 13 06:16:00    67.1887 +08.5644    731.767  10.09
2015 11 13 06:16:10    67.9108 +08.4283    685.818  10.12
2015 11 13 06:16:20    68.6423 +08.2890    640.354  10.16
2015 11 13 06:16:30    69.3833 +08.1464    595.388  10.19
2015 11 13 06:16:40    70.1338 +08.0003    550.937  10.23
2015 11 13 06:16:50    70.8939 +07.8509    507.015  10.26
2015 11 13 06:17:00    71.6636 +07.6980    463.637  10.30
2015 11 13 06:17:10    72.4430 +07.5416    420.820  10.33
2015 11 13 06:17:20    73.2322 +07.3817    378.580  10.37
2015 11 13 06:17:30    74.0311 +07.2182    336.933  10.40
2015 11 13 06:17:40    74.8399 +07.0511    295.896  10.44
2015 11 13 06:17:50    75.6584 +06.8804    255.485  10.47
2015 11 13 06:18:00    76.4868 +06.7061    215.718  10.51
2015 11 13 06:18:10    77.3251 +06.5281    176.611  10.54
2015 11 13 06:18:20    78.1731 +06.3464    138.183  10.57
2015 11 13 06:18:30    79.0310 +06.1610    100.450  10.61
2015 11 13 06:18:40    79.8970 +05.9723     63.503  10.52
2015 11 13 06:18:50    80.6357 +05.8084     32.756  5.479
2015 11 13 06:19:00    80.8375 +05.7551     23.897  1.005
2015 11 13 06:19:10    80.8843 +05.7340     20.992  0.427
2015 11 13 06:19:20    80.9032 +05.7187     18.899  0.286
2015 11 13 06:19:30    80.9120 +05.7055     16.981  0.240
2015 11 13 06:19:40    80.9156 +05.6934     15.166  0.217
2015 11 13 06:19:50    80.9165 +05.6819     13.485  0.202
2015 11 13 06:20:00    80.9160 +05.6707     11.953  0.189
2015 11 13 06:20:10    80.9148 +05.6596     10.559  0.179
2015 11 13 06:20:20    80.9134 +05.6486      9.278  0.172
2015 11 13 06:20:30    80.9119 +05.6377      8.077  0.168
2015 11 13 06:20:40    80.9104 +05.6267      6.935  0.164
2015 11 13 06:20:50    80.9089 +05.6158      5.844  0.161
2015 11 13 06:21:00    80.9073 +05.6048      4.800  0.158
2015 11 13 06:21:10    80.9058 +05.5939      3.796  0.155
2015 11 13 06:21:20    80.9043 +05.5830      2.830  0.153
2015 11 13 06:21:30    80.9027 +05.5721      1.899  0.151
2015 11 13 06:21:40    80.9012 +05.5612      0.998  0.149
2015 11 13 06:21:50    80.8997 +05.5503      0.126  0.147