Recently, I came across an old UFO story with descriptions that strongly suggested a misidentified re-entry from Earth orbit, which I believe correlates with the known re-entry of a piece of hardware from a Russian rocket stage. 1. Sightings The sightings occurred in Morocco on the night of 1976 Sep 18-19 UTC, over an area spanning about 600 km. King Hassan requested the assistance of the U.S. Government to explain them, which resulted in the following message from the U.S. embassy in Morocco to the State Department: http://aad.archives.gov/aad/createpdf?rid=234239&dt=2082 I found the following excerpts most useful analytically: "1. ... the object was on a generally southwest to northeast course, it was a silvery luminous circular shape and gave off intermittent trails of bright sparks and fragments, and made no noise ..." "3. The times of the sightings varied from 0100 to 0200 hours on the morning of 19 September, with the majority of them occurring between 0100 and 0130 hours. Sightings were reported from Agadir, Kalaa-Sraghna, Essaouira, Casablanca, Rabat, Kenitra, Meknes and the Fez region. There was general agreement that the UFO was proceeding on an approximately south to north course, generally parallel to the Moroccan Atlantic coast, at an estimated altitude of 1,000 meters, and that there was absolutely no sound from the UFO." "4. Descriptions of the UFO fell into two general categories, i.e., a type of silver colored luminous flattened ball (disc-shaped), or a large luminous tube-shaped object. Observers reported that the object intermittently emitted bright sparks from the rear." "5. Major Lissaoui said he was sent to brief Datt [U.S. defense attache] on the subject because he had himself sighted the UFO while returning from the city of Kenitra at about 0115 in the morning. He described the UFO as flying parallel to the coast at a relatively slow speed, as if it were an aircraft preparing to land. It first appeared to him as a disc-shaped object, but as it came closer he saw it as a luminous tubular-shaped object." This appears to be a fine example of a re-entry that was perceived as a saucer or cylindrical/cigar-shaped craft, at much closer range than reality. From the context, I took the reported times as local standard, which happened to be the same as UTC. Therefore, I looked for decays that could have occurred on 1976 Sep 19 between 01 h and 02 h UTC. 2. Correlation with 1976-074C / 09051 My query of USSTRATCOM's Space Track database revealed decays listed on each of 1976 Sep 18, 19 and 20 UTC. The decays for the latter two dates do not correlate with the UFO sightings, but the one on Sep 18 did. The object in question is 1976-074C / 09051. Apparently it remained in orbit a bit longer than reported. It was the BOZ ullage motor assembly ejected from the third stage of the Molniya rocket that orbited Molniya 1-35 in July 1976. Mark Wade reports mass of 700 kg, but it is unclear how much of this is fuel. Empty mass as little as 50 to 100 kg would be sufficient to produce a visually impressive re-entry. (It was the re-entry of an ullage motor of the Zond IV launch in 1968 (1968-013C / 03136), that resulted in what became the prototypical saucer/cigar UFO sightings.) http://www.astronautix.com/craft/blo8k78m.htm USSTRATCOM recorded the date of decay as 1976 Sep 18, but my analysis placed it early on Sep 19, within a few minutes of 01:30 UTC, consistent with the time of the sightings. I obtained the TLEs (2-line orbital element sets) for my analysis from Space Track, but they are also available on Jonathan McDowell's site: http://www.planet4589.org/space/elements/09000/S09051 I estimated the date and time of decay using the combination of Alan Pickup's Satevo and Satana decay propagators, which are based on the published research of Dr. Desmond King-Hele, who was among the leading investigators into the mathematics and physics of Earth satellite orbits during the first three decades of the space age. Satevo quickly and reliably propagates a TLE to decay, reports the estimated date and time, and generates propagated TLEs for each revolution up to decay. Satana is a pre-processor for Satevo, that uses the same decay algorithms to fit more accurate decay rates to USSTRATCOM's TLEs, which I have found helps to improve the accuracy of decay estimates. The user specifies three TLEs, ideally spanning several revolutions, and the program generates improved versions. Alan recommends feeding the Satana result to Satevo to make the final decay estimate. I fed USSTRATCOM's final three TLEs to Satana, which yielded this improved estimate of the final TLE: 76074C 173 x 152 km 1 09051U 76074 C 76262.69174196 .11501936 94379-1 44144-3 0 90590 2 09051 62.8815 351.7629 0016273 58.0891 302.0689 16.41174274 9060 Feeding it into Satevo yielded estimated time of decay on Sep 18 at 23:08 UTC, and a TLE propagated to the start of the final revolution: 76074C 137 x 129 km 1 09051U 76074 C 76262.93484476 .71707607 81111+1 54560-3 0 90593 2 09051 62.8782 350.7463 0006829 58.1326 301.9338 16.52439450 9104 Further propagating this TLE using SGP4, revealed that the object would likely have survived well into Sep 19, with the final descent beginning around 01:10 UTC. The re-entry debris train passed the Moroccan coast, moving toward the north-northeast, consistent with items 1 and 3, and it would have been visible from all eight UFO sighting locations. Below is a plot of the ground track: http://satobs.org/seesat_ref/76074C/76074C_track.jpg It should be noted that the altitude profile and point of terminal descent (where the trajectory ends and any surviving fragments descend nearly vertically) is quite uncertain, so although the track is plotted through western Europe, it may not have actually extended that far. If it did, and if the weather was favourable, then sighting reports may exist. The following spreadsheet enables estimating the ephemeris (sky track) of the re-entry train from any location within range. Simply enter the site coordinates on the first sheet. Any portion that rises at least 3 deg above the horizon will be highlighted in red. http://satobs.org/seesat_ref/76074C/76074C_decay_ephemeris.xlsm The second sheet provides the ephemerides for the eight locations in Morocco from which sightings were reported. Below is a summary, listing the coordinates of each location, and the estimated elevation of the re-entry debris train at culmination: N W HASL Culm deg deg m deg Agadir 30.42 9.59 40 18 Essaouira 31.51 9.76 5 27 Kalaa-Sraghna 32.06 7.40 401 13 Casablanca 33.57 7.58 5 20 Rabat 34.01 6.83 10 18 Kenitra 34.26 6.58 10 17 Meknes 33.89 5.55 480 12 Fez Region 34.04 5.00 298 10 The re-entry would have culminated well above the horizon and been easily seen from all of these locations, which span a range of about 600 km across Morocco. It should be noted that the estimated altitude during this period - about 85 km - is somewhat uncertain, but even reducing it to 50 km by the time of closest approach to the Fez region would not invalidate the findings. 3. U.S. Government Response The U.S. government failed to identify the exact cause of the UFO sightings, but it did narrow down the possibilities very well, per this report attributed to Secretary of State Henry Kissinger: http://aad.archives.gov/aad/createpdf?rid=250871&dt=2082 His concluding comment: "8. In order to analyze the Moroccan event thoroughly, further descriptions or photographs from the local area would be needed. In the meantime, one would tend to believe that the event was a meteor, and probably a spectacular one or on account of the description of slow velocity, no noise, and burning fragments, a decaying satellite part, of which there is no precise re-entry record." I do not know whether consideration was given to the possibility that 1976-074C / 09051, which reportedly decayed on Sep 18, could have survived long enough to cause the UFO reports early on Sep 19. I am reasonably confident in my estimate that it did, but make no claim to infallibility; therefore, I welcome and encourage alternative analyses. I would be especially interested to know the results of semi-analytic or numerically integrated re-entry propagations, which may yield a more confident estimate of the time of descent and the altitude profile. Ted Molczan _______________________________________________ Seesat-l mailing list http://mailman.satobs.org/mailman/listinfo/seesat-l
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