[geocentrism] Re: Geosynchronous satellites paper
- From: "Robert Bennett" <robert.bennett@xxxxxxx>
- To: <geocentrism@xxxxxxxxxxxxx>
- Date: Sun, 1 Jul 2007 19:09:46 -0400
Neville,
The new version has problems. The speed of the GS geosat is not zero, using
your g(x) function.
By equating the centripetal force to your gravity force , mg(x), the equivalent
of your eq (3) becomes
V2 = Rg(x)
Using the value of R and x given: at the GeoStationary Distance, GSD, => V2
~= .0081 => V ~= 0.09 km/s
The time to circle the Earth is the period, T = circ/V = 812 hrs = 33.8 days….
An advance of 10.7 degrees/day.
If the geosat were overhead now, it would disappear below the horizon in 9
days….. hardly a geostationary object or descriptive of the actual geosats.
The fundamental problem is that any g(x) you dream up must be zero at the GSD:
g(x=GSD) = 0
Also, according to the citations, the Artemis team decided to slow down the
satellite by ~200 m/s by firing RITA continuously in the opposite direction of
motion for 340 days. Since the velocity is inversely proportional to the square
root of the radius from Eq(3), this operation would cause the satellite to rise
~ 5000 km.
From the Artemis site; F= 0.015 N (the constant thrust of Rita) and payload
plus propellant mass ~ 2000 kg. So Acc = F/m = 7.5 *10-6 m/s2
Thus the final velocity, vf =at = 7.5 *10-6 m/s2 * 340 days ~ 220 m/s.
This approximate calculation is sufficiently close to the target speed of 200
m/s to confirm the validity both of the Artemis description of the orbit
adjustment and of Newton’s Laws.
Robert
-----Original Message-----
From: geocentrism-bounce@xxxxxxxxxxxxx
[mailto:geocentrism-bounce@xxxxxxxxxxxxx]On Behalf Of Neville Jones
Sent: Friday, June 29, 2007 11:20 AM
To: geocentrism@xxxxxxxxxxxxx
Subject: [geocentrism] Re: Geosynchronous satellites paper
Robert,
My original version of the paper did not make it clear enough the difference
between the firing of an ion thruster in the MS case and in the GS case.
I hope that the new version (23.06.07) does clear this up and I thank you for
drawing my attention to it.
Neville.
-----Original Message-----
From: robert.bennett@xxxxxxx
Sent: Wed, 13 Jun 2007 09:31:58 -0400
To: geocentrism@xxxxxxxxxxxxx
Subject: [geocentrism] Re: New paper
Neville,
From the Artemis site; F= 0.015 N (the constant thrust of Rita) and payload
plus propellant mass ~ 2000 kg. So Acc = F/m = 7.5 *10-6 m/s2
For const acc, the final velocity is vf = at.
Suppose Rita is aimed radially down for 12 hours, then up for 12 hours, for 340
days. After each day it will stop rising.
After 12 hours :
vf = at = 7.5 *10-6 m/s2 * 12hrs * 3600sec/hr = .32 m/s
The average velocity v is half of this, v = .16 m/s. (for both the first and
last 12 hours).
The distance traveled in 12 hrs is d=vt = .16 m/s * 12hr * 3600 sec/hr ~= 7 km;
each day Artemis rises ~ 14 km. (The site says 15 km/day)
14 km/day* 340 days ~= 4800 km = 4.8 Mm. The site gives the change in
altitude as (3.6 – 3.1) Mm = 5 Mm.
The simple alternation of thrust direction every half day explains the motion
described for Artemis, using the 2nd law and the kinematic equations for
constant acceleration.
Robert
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