Accelerations

Kurt Jonckheere (kjonckheere@unicall.be)
Tue, 9 Jan 96 21:00:07 +0000 (GMT)

Paul Maley wrotes:
>Kurt reports possible accelerations in 18096 (87-49B),...

After processing my obs from the end of 1995 I can add:
[sa: small amplitude]
>87-49B 95-12-23 [95357] 01:16     PM  271     1.0    8    34.0
 87-49B 95-12-24 [95358] 17:23     KJ   59.9   5.0    2    30     long max, sa
 87-49B 95-12-27 [95361] 17:28     KJ  120.2   0.5    6    20.0
>87-49B 96-01-09 [96009] 11:37     PM  184.2   1.0   31     6.0
Orbital elments of 87049_B = 18096:
YYDDD.FFF       MMdot      Mean Motion
95345.15726151  .00000088  14.33015880
95349.13648559  .00000038  14.33016531
95349.69497286  .00000042  14.33016642
95354.09306003  .00000064  14.33017025
95361.56280107  .00000612  14.33026164
95362.60994688  .00000940  14.33030740
96001.51922929  .00002666  14.33061997

It seems that we have catched up this acceleration from the very beginning!

Allen Thomson sent me some additional elements (thanks), but I still
have a gap between 95354 and 95361 during which the acceleration seems
to have started.

>
>Per Kurt's message of January 7, I would offer up the thought that the 
>accelerations may be caused by a leaky propellant valve rather than fuel 
>corrosion.
I wonder if you or someone else knows the exact mechanism of opening and
closing the valves to see it this is possible.

Some years ago we thought that another reason for accelerations might be
a fuel leak through a hole formed by an impact of a meteorite.  

Although I didn't check all accelerations and elements (it takes a long
time to do so and I don't have old elements) some "conclusions" are:
- there seems to be no relation with major meteor showers 
( something against this it that over the year the showers are still
  in minority compares with the daily activity)
-  a lot of objects have multiple accelerations! This is again confirmed
by 87- 49 B and 88-53B.  I should think that this is difficult to explain
with a hole because when a hole is formed all fuel escapes and there remains
no fuel for later accelerations.  The idea of Paul can solve this if we 
assume that when pressure lowers (as fuel escapes through the valve) the
valve can close again.  When the valve mechanism suffers more from its age
it might open again.

I'm not sure but think that we assumed the thickness of the rocket 
to be about 1 to 2 millimeters.

[Bart and others discussed this some years ago, but maybe some people
of the list can give us new insights!]
Maybe it is a combination of valve-corrosion-impacts over the years...???

>
These very fast reactions (I mean observations from all over the world
of peculiar objects) was something I hoped for when Bart started with
this list.  Thanks to all and go on!

Greetings,

Kurt Jonckheere (kjonckheere@unicall.be)