Forse un'esplosione per il Delta 4 - DMSP F17?

Sembra ci sia stato qualche problema con il lanciatore Boeing, SpaceCom ha infatti catalogato oltre 60 oggetti relativi al lancio, avvenuto il 4 Novembre scorso in cui è stato immesso in orbita il satellite meteo militare DMSP F17, segno questo, quasi inequivocabile, di un’esplosione. L’esplosione è avvenuta probabilmente dopo il rilascio del satellite, qualche secondo dopo l’ultima accensione dell’ultimo stadio che avrebbe dovuto essere inserito in un orbita di rientro.

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Spacecom has cataloged 60 debris objects associated with the Delta 4 rocket that placed DMSP F17 into orbit. The catalog numbers are 29540 to 29599. My analysis of the elsets for a few of these objects leads me to the conclusion that an explosive event happened many minutes after the rocket performed its maneuver to enter a decay orbit. So I believe that the main rocket body did re-enter and that all these pieces of debris are very tiny.

Mike McCants

There are now almost 300 tles for the 60 objects that first showed up on Nov. 14.

The mean motion for the payload and its rocket were approximately
14.13 revs/day. The mean motions for the debris objects range from
14.17 through 14.25 to about 14.34 revs/day. This seems like a fairly
small “dispersion”. So my theory (today) is that the rocket started
its disposal/re-entry burn and burned for only a very short time
and changed its mean motion from 14.13 to 14.25 revs/day. Then some
time later, the rocket exploded. The main piece of the rocket (yet
to be cataloged) would remain in a 14.25 revs/day orbit. When it
is cataloged, it will have a much lower drag term compared to the
60 tiny pieces.

The theory of multiple objects with different velocities (but the
same energy) leaving from a single point could lead to orbits that
intersect twice - once at that point of origin and again about
one-half of an orbit later. But objects with higher or lower energies
should be above or below the objects with the same energy at the point
that is about one-half way around the orbit. Because I am extrapolating
backwards in time from Nov. 14, 15, or 16 to Nov. 4 with tles that
have non-zero and changing drag terms, the agreement among the
extrapolated orbits on Nov. 4 is not very high.

Many of these tles seem to go through the following two volumes
in time and space:

Nov. 4, from 15:55 to 16:05 UT - height 500 to 520 miles
latitude 30 to 35 south, longitude 162 west.

Nov. 4, from 17:00 to 17:10 UT - height 500 to 520 miles
latitude 65 to 80 degrees north, longitude 40 east -20/+70 degrees.

Note that the launch was at 13:53 UT and the disposal burn was
scheduled for 15:44 UT. So 16:00 is only 16 minutes later than that.
The predicted position for the rocket at 16:00 UT would have been:
height 526 miles, latitude 28.9 south, longitude 161 west if no
burn took place.

However, there are a number of pieces that fit the 17:05 UT time
better than the 16:00 UT time and only a few pieces that fit the
16:00 time better than the 17:05 time. Of course the 17:05 time
is 81 minutes after the scheduled burn.

Mike McCants

It looks like the third stage uses LH2/LOX. Wikipedia has a picture at I would suspect the failure mechanism to be overpressure. Perhaps the relief valves had some problem?

It seems that an overpressure would be more likely to occur further away
from shutdown than closer to it (i.e. 81 minutes after the burn more likely
than 16 minutes). Perhaps there was some thermal soak back from the engine
into the LOX tank? Just speculating.

Bill Bard

Quindi se ho capito bene è stato l’ultimo stadio del vettore ad esplodere ma soltanto dopo aver rilasciato il satellite che quindi sarebbe stato inserito regolarmente in orbita…
Allora DMSP-17 è salvo?

e se fosse un depistaggio?

http://www.space.com/businesstechnology/technology/mystery_monday_050103.html

c’è il sospetto che la messa in orbita del misty (satellite stealth) sia stata coperta con un falso lancio fallito. Tu nelle tue notti di osservazione hai mai visto qualcosa di strano?

Quindi se ho capito bene è stato l'ultimo stadio del vettore ad esplodere ma soltanto dopo aver rilasciato il satellite che quindi sarebbe stato inserito regolarmente in orbita... Allora DMSP-17 è salvo?

Si sembra sia così, il satellite è regolarmente in orbita, e per ora anche i detriti, che fino ad ora sono 60 catalogati.

e se fosse un depistaggio?

http://www.space.com/businesstechnology/technology/mystery_monday_050103.html

c’è il sospetto che la messa in orbita del misty (satellite stealth) sia stata coperta con un falso lancio fallito. Tu nelle tue notti di osservazione hai mai visto qualcosa di strano?

Non ho capito cosa intendi, qui il satellite c’è ed è regolarmente in orbita e ci sono regolarmente anche i detriti dell’upper stage, anche perchè non era un satellite classificato (infatti i tle non sono classificati ma liberi), era un “regolare” satellite meteo… il misty era poi stato lanciato con lo shuttle e si era parlato di un malfunzionamento, mi sembra di capire, cosa ovviamente non osservabile da terra…

questo è il satellite catalogato (il primo), con relativi rottami al seguito (gli altri):

2006-050A 29522 US 101.9 98.8 855 842 3.5241 DMSP 5D-3 F17 Launched (11/04/2006) 2006-050D 29525 US 101.9 98.8 851 845 N/A DMSP 5D-3 F17 DEB Launched (11/04/2006) 2006-050C 29524 US 101.9 98.8 853 845 0.0662 DMSP 5D-3 F17 DEB Launched (11/04/2006) 2006-050B 29523 US 101.9 98.8 863 831 0.0062 DELTA 4 R/B Launched (11/04/2006) Decayed [11/04/2006] 2006-050BS 29600 US NO ELEMENTS AVAILABLE N/A DMSP 5D-3 FLT 17 DEB Launched (11/04/2006)

qui c’è la lista di detriti dell’upper stage:

2006-050BR 29599 US 101.6 98.8 851 814 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BQ 29598 US 101.5 98.8 847 814 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BP 29597 US 101.5 98.8 861 799 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BN 29596 US 101.4 98.8 860 791 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BM 29595 US 101.0 98.8 848 766 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BL 29594 US 100.4 98.7 853 703 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BK 29593 US 101.6 98.8 848 820 0.0560 DELTA 4 DEB Launched (11/04/2006) 2006-050BJ 29592 US 101.5 98.8 853 811 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BH 29591 US 101.3 98.8 853 789 0.0150 DELTA 4 DEB Launched (11/04/2006) 2006-050BG 29590 US 101.3 98.8 852 790 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BF 29589 US 101.2 98.8 854 775 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BE 29588 US 101.1 98.8 849 769 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BD 29587 US 101.0 98.9 851 763 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BC 29586 US 100.5 98.6 856 704 0.0450 DELTA 4 DEB Launched (11/04/2006) 2006-050BB 29585 US 100.4 98.7 861 698 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050BA 29584 US 100.0 98.7 846 668 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AZ 29583 US 101.2 98.7 854 775 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AY 29582 US 101.0 98.8 856 754 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AX 29581 US 101.1 98.7 853 770 0.0220 DELTA 4 DEB Launched (11/04/2006) 2006-050AW 29580 US 101.0 98.8 849 767 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AV 29579 US 101.3 98.8 852 793 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AU 29578 US 101.3 98.8 853 784 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AT 29577 US 101.3 98.6 862 776 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AS 29576 US 99.9 98.6 847 657 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AR 29575 US 100.5 98.7 853 714 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AQ 29574 US 101.0 98.8 854 754 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AP 29573 US 100.9 98.7 850 752 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AN 29572 US 101.0 98.8 848 766 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AM 29571 US 100.8 98.8 848 741 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AL 29570 US 100.8 98.7 860 733 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AK 29569 US 100.3 98.6 851 699 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AJ 29568 US 100.2 98.8 850 684 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AH 29567 US 100.0 98.7 848 672 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AG 29566 US 100.0 98.6 851 664 0.0110 DELTA 4 DEB Launched (11/04/2006) 2006-050AF 29565 US 95.8 98.6 750 365 0.0020 DELTA 4 DEB Launched (11/04/2006) 2006-050AE 29564 US 101.6 98.8 851 819 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AD 29563 US 101.6 98.8 852 820 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AC 29562 US 100.9 98.9 851 750 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AB 29561 US 100.1 98.6 849 675 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050AA 29560 US 99.9 99.1 845 666 0.0110 DELTA 4 DEB Launched (11/04/2006) 2006-050Z 29559 US 101.0 98.8 849 768 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050Y 29558 US 101.7 98.8 847 829 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050X 29557 US 101.5 98.8 847 811 0.0590 DELTA 4 DEB Launched (11/04/2006) 2006-050W 29556 US 101.2 98.9 852 774 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050V 29555 US 101.1 98.8 851 771 0.0250 DELTA 4 DEB Launched (11/04/2006) 2006-050U 29554 US 100.9 98.8 850 754 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050T 29553 US 100.8 99.0 849 739 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050S 29552 US 100.8 98.5 857 736 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050R 29551 US 100.7 98.8 864 718 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050Q 29550 US 100.6 98.7 860 715 0.0820 DELTA 4 DEB Launched (11/04/2006) 2006-050P 29549 US 100.5 98.9 852 718 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050N 29548 US 101.6 98.8 851 817 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050M 29547 US 101.6 98.8 847 819 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050L 29546 US 101.5 98.8 849 815 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050K 29545 US 101.6 98.8 850 819 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050J 29544 US 100.4 98.7 854 698 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050H 29543 US 101.6 98.8 850 816 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050G 29542 US 98.0 98.5 835 487 N/A DELTA 4 DEB Launched (11/04/2006) 2006-050F 29541 US 91.0 98.5 367 277 0.0430 DELTA 4 DEB Launched (11/04/2006) 2006-050E 29540 US 99.6 98.5 845 635 N/A DELTA 4 DEB Launched (11/04/2006)