[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: AO-40 Orbital Stability



Stacey:

Your pictures bear out WHY it is important to have
a burn of the 400 N motor.  The instability (perigee
bouncing around) is a real problem when your
perigee is 360 km.  The graphs are so busy that
I can't make out the units.  What are the maxima
and minima of the perigee heights AND what
was the apogee of the spacecraft.  It was not
clear that your graphs assumed the current
conditions.

Thanks!
Bob


Bob

----- Original Message -----
From: "Jon Ogden" <na9d@mindspring.com>
To: "Stacey E. Mills, M.D." <w4sm@cstone.net>; "Amsat Bulletin Board"
<amsat-bb@AMSAT.Org>
Sent: Monday, December 25, 2000 12:35 AM
Subject: Re: [amsat-bb] AO-40 Orbital Stability


> on 12/24/00 6:17 PM, Stacey E. Mills, M.D. at w4sm@cstone.net wrote:
>
> >
> > I'll take a shot at this one.  The orbit is incredibly stable.  It's not
> > the eccentricity per se that creates instability.  It's the combination
of
> > eccentricity and high inclination, along with RAAN and ArgP that has the
> > potential for instability due to solar/lunar forces.  The current low
> > inclination orbit is highly stable.
>
> Stacey,
>
> Thanks for the explanation.  That's good to know.  It was also a good
quick
> lesson in orbital mechanics!  :-)
>
> Good luck to you and the rest of the command team.  This has got to be
hard
> and I am sure that you guys all would love to get that bird to reset and
> come back in operation on Christmas day.  It would be a great Christmas
> present.  But I, at least, would rather have you enjoy the day with your
> family than trying to get AO-40 back on line.  We can do that on Tuesday!
>
> Have a great Holiday!  Thank you again.
>
> 73,
>
> Jon
> NA9D
>
> -------------------------------------
> Jon Ogden
> NA9D (ex: KE9NA)
>
> Member:  ARRL, AMSAT, DXCC, NRA
>
> http://www.qsl.net/ke9na
>
> "A life lived in fear is a life half lived."
>
> ----
> Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
> To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
>

----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home