A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Astronomy and Astrophysics » Amateur Astronomy
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Astra geostationary satellites through telescope



 
 
Thread Tools Display Modes
  #1  
Old November 30th 18, 10:36 AM posted to sci.astro.amateur
StarDust
external usenet poster
 
Posts: 732
Default Astra geostationary satellites through telescope

https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are directly above the equator, they can be slightly inclined whether by design or insertion failure. The satellite's gyros will compensate for the movement to keep the footprint centered. Sirius XM sats do a huge "figure 8" from North to South and back to ensure a uniform footprint for moving vehicles. A. Kemp - Lockheed Martin Astronautics
  #2  
Old November 30th 18, 03:15 PM posted to sci.astro.amateur
Chris L Peterson
external usenet poster
 
Posts: 10,007
Default Astra geostationary satellites through telescope

On Fri, 30 Nov 2018 01:36:04 -0800 (PST), StarDust
wrote:

https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are directly above the equator, they can be slightly inclined whether by design or insertion failure. The satellite's gyros will compensate for the movement to keep the footprint centered. Sirius XM sats do a huge "figure 8" from North to South and back to ensure a uniform footprint for moving vehicles. A. Kemp - Lockheed Martin Astronautics?


By definition, all geostationary satellites are above the equator, and
do not oscillate. If they are inclined, by have a 24 hour orbit, they
are called geosynchronous, and show that north/south oscillation.

All geostationary satellites are geosynchronous, but not all
geosynchronous satellites are geostationary.
  #3  
Old November 30th 18, 05:23 PM posted to sci.astro.amateur
Gerald Kelleher
external usenet poster
 
Posts: 1,551
Default Astra geostationary satellites through telescope

On Friday, November 30, 2018 at 2:15:34 PM UTC, Chris L Peterson wrote:
On Fri, 30 Nov 2018 01:36:04 -0800 (PST), StarDust
wrote:

https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are directly above the equator, they can be slightly inclined whether by design or insertion failure. The satellite's gyros will compensate for the movement to keep the footprint centered. Sirius XM sats do a huge "figure 8" from North to South and back to ensure a uniform footprint for moving vehicles. A. Kemp - Lockheed Martin Astronautics?


By definition, all geostationary satellites are above the equator, and
do not oscillate. If they are inclined, by have a 24 hour orbit, they
are called geosynchronous, and show that north/south oscillation.

All geostationary satellites are geosynchronous, but not all
geosynchronous satellites are geostationary.


Cracks me up !, the nuisances will be along soon to tell the newsgroup that a geostationary satellite doesn't remain fixed to a longitude meridian as the planet 'doesn't' turn once each 24 hours or at a rate of 15 degrees per hour.

A geostationary satellite doesn't include information of the surface rotation parallel to the orbital plane as a function of the Earth's orbital motion and best understood by the motion of the North/South Poles in small circles coincident with the Arctic/Antarctic circles. Copernicus originally got it right -

" The third is the motion in declination. For, the axis of the daily rotation is not parallel to the Grand Orb's axis, but is inclined [to it at an angle that intercepts] a portion of a circumference, in our time about 23 1/2°. Therefore, while the earth's center always remains in the plane of the ecliptic, that is, in the circumference of a circle of the Grand Orb, the earth's poles rotate, both of them describing small circles about centers [lying on a line that moves] parallel to the Grand Orb's axis. The period of this motion also is a year, but not quite, being nearly equal to the Grand Orb's [revolution]." Copernicus , Commentariolus

http://copernicus.torun.pl/en/archiv...=transkrypcja&


Strange that this under-developed adult would venture into a thread where planetary rotation is being discussed after spending two decades hiding in the shadows.

  #4  
Old December 1st 18, 08:34 AM posted to sci.astro.amateur
Paul Schlyter[_3_]
external usenet poster
 
Posts: 1,344
Default Astra geostationary satellites through telescope

On Fri, 30 Nov 2018 07:15:34 -0700, Chris L Peterson
wrote:
On Fri, 30 Nov 2018 01:36:04 -0800 (PST), StarDust


wrote:


https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are

directly above the equator, they can be slightly inclined whether by
design or insertion failure. The satellite's gyros will compensate
for the movement to keep the footprint centered. Sirius XM sats do a
huge "figure 8" from North to South and back to ensure a uniform
footprint for moving vehicles. A. Kemp - Lockheed Martin
Astronautics?

By definition, all geostationary satellites are above the equator,

and
do not oscillate. If they are inclined, by have a 24 hour orbit,

they
are called geosynchronous, and show that north/south oscillation.


If so, geostationary satellites do not exist since it is impossible
to keep a satellite exactly above the equator at all times. There
will always be some small deviations.

All geostationary satellites are geosynchronous, but not all
geosynchronous satellites are geostationary.

  #5  
Old December 1st 18, 10:01 AM posted to sci.astro.amateur
Gerald Kelleher
external usenet poster
 
Posts: 1,551
Default Astra geostationary satellites through telescope

The whole point of geostationary is that it remains fixed to a surface longitude at the Equator. When set off against the ecliptic plane, the satellite will appear to trace the same path as the Equator as it turns as a function of the Earth's orbital motion -

http://afewbitsmore.com/img/2015_ecliptic.png

All the serious sounding voodoo only expose how uncomfortable people are when discussing rotational and orbital dynamics and orientations whereas those free of the celestial sphere constraints just view and judge these things without fear of offending the hapless RA/Dec enthusiasts whether theorists of magnification hobbyists.

It leads to a discussion on why satellites/moons of planets like Jupiter and Uranus follow their planet's Equator while the Earth's moon doesn't. Of course people don't do originality but at least this forum has been cleared out of those who are afraid to challenge outgrown and flawed perspectives.

  #6  
Old December 1st 18, 03:26 PM posted to sci.astro.amateur
Chris L Peterson
external usenet poster
 
Posts: 10,007
Default Astra geostationary satellites through telescope

On Sat, 01 Dec 2018 08:34:18 +0100, Paul Schlyter
wrote:

On Fri, 30 Nov 2018 07:15:34 -0700, Chris L Peterson
wrote:
On Fri, 30 Nov 2018 01:36:04 -0800 (PST), StarDust


wrote:


https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are

directly above the equator, they can be slightly inclined whether by
design or insertion failure. The satellite's gyros will compensate
for the movement to keep the footprint centered. Sirius XM sats do a
huge "figure 8" from North to South and back to ensure a uniform
footprint for moving vehicles. A. Kemp - Lockheed Martin
Astronautics?

By definition, all geostationary satellites are above the equator,

and
do not oscillate. If they are inclined, by have a 24 hour orbit,

they
are called geosynchronous, and show that north/south oscillation.


If so, geostationary satellites do not exist since it is impossible
to keep a satellite exactly above the equator at all times. There
will always be some small deviations.


Geostationary satellites exist because they have active systems to
maintain their position. Indeed, once those active systems fail they
do drift out of their geostationary orbit. In most cases,
geostationary satellites nearing the end of their life (or their fuel
supply) are deliberately pushed into a higher orbit in order to free
up valuable and limited space in the geostationary orbital band.
  #7  
Old December 1st 18, 03:51 PM posted to sci.astro.amateur
Gerald Kelleher
external usenet poster
 
Posts: 1,551
Default Astra geostationary satellites through telescope

On Saturday, December 1, 2018 at 2:26:08 PM UTC, Chris L Peterson wrote:
On Sat, 01 Dec 2018 08:34:18 +0100, Paul Schlyter
wrote:

On Fri, 30 Nov 2018 07:15:34 -0700, Chris L Peterson
wrote:
On Fri, 30 Nov 2018 01:36:04 -0800 (PST), StarDust


wrote:


https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are

directly above the equator, they can be slightly inclined whether by
design or insertion failure. The satellite's gyros will compensate
for the movement to keep the footprint centered. Sirius XM sats do a
huge "figure 8" from North to South and back to ensure a uniform
footprint for moving vehicles. A. Kemp - Lockheed Martin
Astronautics?

By definition, all geostationary satellites are above the equator,

and
do not oscillate. If they are inclined, by have a 24 hour orbit,

they
are called geosynchronous, and show that north/south oscillation.


If so, geostationary satellites do not exist since it is impossible
to keep a satellite exactly above the equator at all times. There
will always be some small deviations.


Geostationary satellites exist because they have active systems to
maintain their position. Indeed, once those active systems fail they
do drift out of their geostationary orbit. In most cases,
geostationary satellites nearing the end of their life (or their fuel
supply) are deliberately pushed into a higher orbit in order to free
up valuable and limited space in the geostationary orbital band.


Where are all the nuisances who, for the last 20 years, argue that the Earth's rotation is fixed to stellar circumpolar despite geostationary satellites maintaining a fix on longitude and one sunrise/sunset each 24 hour day ?.

Everyone learned the lesson, at least those who can despite all those fine academic institutions preaching a fiction of more rotations than 24 hour days.

  #8  
Old December 1st 18, 08:55 PM posted to sci.astro.amateur
Mike Collins[_4_]
external usenet poster
 
Posts: 2,824
Default Astra geostationary satellites through telescope

Gerald Kelleher wrote:
On Friday, November 30, 2018 at 2:15:34 PM UTC, Chris L Peterson wrote:
On Fri, 30 Nov 2018 01:36:04 -0800 (PST), StarDust
wrote:

https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are directly
above the equator, they can be slightly inclined whether by design or
insertion failure. The satellite's gyros will compensate for the
movement to keep the footprint centered. Sirius XM sats do a huge
"figure 8" from North to South and back to ensure a uniform footprint
for moving vehicles. A. Kemp - Lockheed Martin Astronautics?


By definition, all geostationary satellites are above the equator, and
do not oscillate. If they are inclined, by have a 24 hour orbit, they
are called geosynchronous, and show that north/south oscillation.

All geostationary satellites are geosynchronous, but not all
geosynchronous satellites are geostationary.


Cracks me up !, the nuisances will be along soon to tell the newsgroup
that a geostationary satellite doesn't remain fixed to a longitude
meridian as the planet 'doesn't' turn once each 24 hours or at a rate of
15 degrees per hour.

A geostationary satellite doesn't include information of the surface
rotation parallel to the orbital plane as a function of the Earth's
orbital motion and best understood by the motion of the North/South Poles
in small circles coincident with the Arctic/Antarctic circles. Copernicus
originally got it right -

" The third is the motion in declination. For, the axis of the daily
rotation is not parallel to the Grand Orb's axis, but is inclined [to it
at an angle that intercepts] a portion of a circumference, in our time
about 23 1/2°. Therefore, while the earth's center always remains in the
plane of the ecliptic, that is, in the circumference of a circle of the
Grand Orb, the earth's poles rotate, both of them describing small
circles about centers [lying on a line that moves] parallel to the Grand
Orb's axis. The period of this motion also is a year, but not quite,
being nearly equal to the Grand Orb's [revolution]." Copernicus , Commentariolus

http://copernicus.torun.pl/en/archiv...=transkrypcja&


Strange that this under-developed adult would venture into a thread where
planetary rotation is being discussed after spending two decades hiding in the shadows.



https://en.wikipedia.org/wiki/Dunnin...3Kruger_effect


  #9  
Old December 1st 18, 10:55 PM posted to sci.astro.amateur
palsing[_2_]
external usenet poster
 
Posts: 3,068
Default Astra geostationary satellites through telescope

On Saturday, December 1, 2018 at 6:51:49 AM UTC-8, Gerald Kelleher wrote:
On Saturday, December 1, 2018 at 2:26:08 PM UTC, Chris L Peterson wrote:
On Sat, 01 Dec 2018 08:34:18 +0100, Paul Schlyter
wrote:

On Fri, 30 Nov 2018 07:15:34 -0700, Chris L Peterson
wrote:
On Fri, 30 Nov 2018 01:36:04 -0800 (PST), StarDust

wrote:

https://www.youtube.com/watch?v=rIesWBTUeiI

It's called Geostationary Oscillation. Not all geo sats are
directly above the equator, they can be slightly inclined whether by
design or insertion failure. The satellite's gyros will compensate
for the movement to keep the footprint centered. Sirius XM sats do a
huge "figure 8" from North to South and back to ensure a uniform
footprint for moving vehicles. A. Kemp - Lockheed Martin
Astronautics?

By definition, all geostationary satellites are above the equator,
and
do not oscillate. If they are inclined, by have a 24 hour orbit,
they
are called geosynchronous, and show that north/south oscillation.

If so, geostationary satellites do not exist since it is impossible
to keep a satellite exactly above the equator at all times. There
will always be some small deviations.


Geostationary satellites exist because they have active systems to
maintain their position. Indeed, once those active systems fail they
do drift out of their geostationary orbit. In most cases,
geostationary satellites nearing the end of their life (or their fuel
supply) are deliberately pushed into a higher orbit in order to free
up valuable and limited space in the geostationary orbital band.


Where are all the nuisances who, for the last 20 years, argue that the Earth's rotation is fixed to stellar circumpolar despite geostationary satellites maintaining a fix on longitude and one sunrise/sunset each 24 hour day ?.

Everyone learned the lesson, at least those who can despite all those fine academic institutions preaching a fiction of more rotations than 24 hour days.


It's not "all those fine academic institutions" that is preaching the fiction...
  #10  
Old December 1st 18, 11:05 PM posted to sci.astro.amateur
Gerald Kelleher
external usenet poster
 
Posts: 1,551
Default Astra geostationary satellites through telescope

On Saturday, December 1, 2018 at 9:55:53 PM UTC, palsing wrote:


It's not "all those fine academic institutions" that is preaching the fiction...


No love for God then no love of God for you - no love of creation then no love of creation for you. It all comes down to kindness and sharing and not superiority/inferiority and if you come to the end of your productive and creative life without experiencing this great lesson, it is all worthless pretense.

https://apod.nasa.gov/apod/ap181201.html

It is true that stellar circumpolar motion is due to daily rotation , however, it is not possible to tie the rotation or the Earth directly to celestial sphere rotation using timekeeping as that system is already occupied by the 24 hour and Lat/Long systems.

The natural noon cycle is never 24 hours so using a sample of different total lengths of time taken over weeks or months it takes a location to turn to noon ,when they are combined and then divided evenly, the mean value generates the 24 hour day and equable hours,minutes and seconds. This 'average' day is then used as a substitute for 'constant' rotation at a rate of 15 degrees per hour, 4 minutes for each degree of rotation and one 360 degree rotation in 24 hours. The trick was switching 'average' for 'constant' as , for example, the average flow of water through a pipe is much the same as the constant flow of water through the same pipe.

What was left behind in trying to model 360 degree rotation to stellar circumpolar motion using timekeeping was the component which creates the natural inequality in the noon cycle in the first place before the variations in noon were converted into a equal 24 hour measure. This component is best understood through the Earth's polar day/ night cycle where Polar sunrise/sunset happens on the Equinoxes and Polar noon/midnight happens on the Solstices.

Geostationary satellites fixed to a longitude meridian follow the changes in orientation of the Equator to the ecliptic plane and not the orbital surface rotation parallel to the orbital plane.

All the institutions in the world can't create an astronomical composition no more than they can create a musical composition but then again beauty is in the eye and ear of the beholder.



 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Geostationary satellites Gerald Kelleher Amateur Astronomy 7 November 10th 18 07:44 AM
ASTRO: Geostationary satellites and Arp 146 Rick Johnson[_2_] Astro Pictures 1 May 24th 09 07:48 PM
How to calculate eclipse for geostationary satellites ? HJK UK Astronomy 3 October 10th 06 02:31 PM
How to calculate eclipse for geostationary satellites ? HJK Misc 0 September 30th 06 06:49 PM
geostationary satellites [email protected] Astronomy Misc 3 April 25th 06 09:26 PM


All times are GMT +1. The time now is 10:56 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.