Apollo 8 - Navigation musings
Re: Apollo 8 - Navigation musings
Just finished reading "Carrying The Fire" by Michael Collins.
Not too technical but a good read.
Pulls few punches regarding fellow astronauts.
PP
Not too technical but a good read.
Pulls few punches regarding fellow astronauts.
PP
Re: Apollo 8 - Navigation musings
Sidevalve:
Read it and agree.
PP
Read it and agree.
PP
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Re: Apollo 8 - Navigation musings
A small correction. Vehicles lifting a body into equatorial earth orbit do not rise vertically. In order to take advantage of the earth's rotational speed a y axis shift to the east is made shortly after lift off. This is why launch sites are as near as possible to the equator where the perceived rotational speed of the earth is at a maximum. Polar insertions launch directly south, there is also a y axis rotation, but for different reasons, and they lift smaller payloads for the same fuel expended as they cannot take advantage of the earth's rotation.
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Re: Apollo 8 - Navigation musings
Hence (for example) the reasoning for positioning of the French rocket launch site and European spaceport to the northwest of Kourou in French Guiana!OFSO wrote: ↑Sun Feb 23, 2020 6:17 amA small correction. Vehicles lifting a body into equatorial earth orbit do not rise vertically. In order to take advantage of the earth's rotational speed a y axis shift to the east is made shortly after lift off. This is why launch sites are as near as possible to the equator where the perceived rotational speed of the earth is at a maximum. Polar insertions launch directly south, there is also a y axis rotation, but for different reasons, and they lift smaller payloads for the same fuel expended as they cannot take advantage of the earth's rotation.
While it is irrelevant, on the basis of the fact that the effect is negligible in the context of the rocket loads lifted, is is interesting to note that gravity is also less at the equator due to the greater distance between the earth's surface and the centre of the earth on account of the bulge there as a result of the greater rotational speed (angular momentum) as the the earth shape is that of an oblate spheroid.
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."
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Re: Apollo 8 - Navigation musings
So that's what caused my dizzy spells when I was on Gan!TheGreenGoblin wrote: ↑Sun Feb 23, 2020 9:18 amWhile it is irrelevant, on the basis of the fact that the effect is negligible in the context of the rocket loads lifted, is is interesting to note that gravity is also less at the equator due to the greater distance between the earth's surface and the centre of the earth on account of the bulge there as a result of the greater rotational speed (angular momentum) as the the earth shape is that of an oblate spheroid.
I thought it was the duty free booze!
Cynicism improves with age
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Re: Apollo 8 - Navigation musings
ian16th wrote: ↑Sun Feb 23, 2020 10:35 amSo that's what caused my dizzy spells when I was on Gan!TheGreenGoblin wrote: ↑Sun Feb 23, 2020 9:18 amWhile it is irrelevant, on the basis of the fact that the effect is negligible in the context of the rocket loads lifted, is is interesting to note that gravity is also less at the equator due to the greater distance between the earth's surface and the centre of the earth on account of the bulge there as a result of the greater rotational speed (angular momentum) as the the earth shape is that of an oblate spheroid.
I thought it was the duty free booze!
You should also age faster at the equator in relation to a person at higher latitudes due to the special relativistic effects due to the lower gravity (arising from the rotational bulge) but due to the time dilation effect resulting from the higher rotational speed of the earth as a result of the earth's bulge there, this effect is neatly cancelled out. One extra nano second gained to have another drink might have been good!
The Lord giveth and the Lord taketh away.
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."
Re: Apollo 8 - Navigation musings
Another larger-than-life former astronaut - mentioned in "Riding Rockets" is 'Hoot' Gibson (F-14s)..
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Re: Apollo 8 - Navigation musings
Flew as a pilot for Southwest airlines until he was forced to retire at 60!
Though you remain
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."
Convinced
"To be alive
You must have somewhere
To go
Your destination remains
Elusive."