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Re: Imagine the first landing strip on the moon

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  Re: Imagine the first landing strip on the moon wobbly <wobbly@dont-email.me> - 2015-07-28 22:20 +0000
    Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-07-29 03:14 +0200
      Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-07-30 22:38 +0200
        Re: Imagine the first landing strip on the moon wobbly <wobbly@dont-email.me> - 2015-08-02 17:02 +0000
          Re: Imagine the first landing strip on the moon kefischer <emoneyjoe@iglou.com> - 2015-08-02 14:40 -0400
            Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-08-04 04:32 +0200
              Re: Imagine the first landing strip on the moon John Gogo <jfgogo22@yahoo.com> - 2015-08-03 19:56 -0700
              Re: Imagine the first landing strip on the moon John Gogo <jfgogo22@yahoo.com> - 2015-08-03 19:58 -0700
              Re: Imagine the first landing strip on the moon Bohuš Matuška <bohu@paranetnet.net> - 2015-08-04 15:14 +0000
                Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-08-05 06:54 +0200
                  Re: Imagine the first landing strip on the moon Bohuš Matuška <bohu@paranetnet.net> - 2015-08-05 13:35 +0000
                    Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-08-06 06:42 +0200
                      Re: Imagine the first landing strip on the moon John Gogo <jfgogo22@yahoo.com> - 2015-08-05 22:24 -0700
                        Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-08-07 08:09 +0200
                          Re: Imagine the first landing strip on the moon kefischer <emoneyjoe@iglou.com> - 2015-08-07 02:41 -0400
                            Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-08-07 10:05 +0200
                            Re: Imagine the first landing strip on the moon Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-07 10:29 +0200
                              Re: Imagine the first landing strip on the moon kefischer <emoneyjoe@iglou.com> - 2015-08-07 06:21 -0400
                                Re: Imagine the first landing strip on the moon Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-07 13:42 +0200
                                  Re: Imagine the first landing strip on the moon Emmerich Schultheiß <emme@noemail.thx> - 2015-08-07 13:01 +0000
                                    Re: Imagine the first landing strip on the moon Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-07 16:00 +0200
                                      Re: Imagine the first landing strip on the moon Emmerich Schultheiß <emme@noemail.thx> - 2015-08-07 14:11 +0000
                                        Re: Imagine the first landing strip on the moon Thomas Heger <ttt_heg@web.de> - 2015-08-07 18:26 +0200
                                  Re: Imagine the first landing strip on the moon kefischer <emoneyjoe@iglou.com> - 2015-08-07 11:20 -0400
                                    Re: Imagine the first landing strip on the moon Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-07 18:07 +0200
                                    Re: Imagine the first landing strip on the moon Emmerich Schultheiß <emme@noemail.thx> - 2015-08-07 17:18 +0000
                                      Re: Imagine the first landing strip on the moon pnalsing@gmail.com - 2015-08-07 10:41 -0700
                                        Re: Imagine the first landing strip on the moon Emmerich Schultheiß <emme@noemail.thx> - 2015-08-07 17:49 +0000
                                          Re: Imagine the first landing strip on the moon pnalsing@gmail.com - 2015-08-07 11:15 -0700
                                            Re: Imagine the first landing strip on the moon Emmerich Schultheiß <emme@noemail.thx> - 2015-08-07 18:26 +0000
                                            Re: Imagine the first landing strip on the moon kefischer <emoneyjoe@iglou.com> - 2015-08-07 14:31 -0400
                                              Re: Imagine the first landing strip on the moon pnalsing@gmail.com - 2015-08-07 11:46 -0700
                                                Re: Imagine the first landing strip on the moon kefischer <emoneyjoe@iglou.com> - 2015-08-07 15:58 -0400
                                                  Re: Imagine the first landing strip on the moon pnalsing@gmail.com - 2015-08-07 19:43 -0700
                                                    Re: Imagine the first landing strip on the moon John Gogo <jfgogo22@yahoo.com> - 2015-08-07 20:47 -0700
                            Re: Imagine the first landing strip on the moon John Gogo <jfgogo22@yahoo.com> - 2015-08-07 18:49 -0700

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#358945 — Re: Imagine the first landing strip on the moon

Thomas Heger wrote:

> How much more the latter effect is compared to saving due to lower
> gravity, that is depending on velocity. So we had to assume some sort of
> velocity, like orbit velocity around the moon. This is still rather fast
> and most the fuel is required, to reduce the velocity to zero and a
> little to prevent the spaceship from dropping down.

Are you just saying that this task is not achievable without a computer?

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#358960

Am 29.07.2015 00:20, schrieb wobbly:
> Thomas Heger wrote:
>
>> How much more the latter effect is compared to saving due to lower
>> gravity, that is depending on velocity. So we had to assume some sort of
>> velocity, like orbit velocity around the moon. This is still rather fast
>> and most the fuel is required, to reduce the velocity to zero and a
>> little to prevent the spaceship from dropping down.
>
> Are you just saying that this task is not achievable without a computer?


No. It is possible without computers, but is difficult. Certainly the 
reverted thrust is not easy to control, since you have a set of 
difficult tasks:

point the engine in the right direction (opposite to the flight path)

make the spaceship slow down according to the desired flightpath 
(properly control the thrust)

target the planned landing zone

have exactly zero velocity in horizontal and vertical direction exactly 
at the surface

You would need to have an eye on the fuel used, since that is a critical 
point.

since you have not much additional fuel, you have only one try and no 
means for corrections while on descent


All of the tasks are quite difficult, but could be achieved without a 
computer (even if such a device would be helpful).

But VERY difficult is the problem of the needed fuel, since the craft 
cannot use a parachute to slow down. It could only decelerate by 
reversed thrust and that is something, that consumes a LOT of fuel.

TH

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#359117

Am 30.07.2015 15:34, schrieb Sylvia Else:

>>>> Are you just saying that this task is not achievable without a
>>>> computer?
>>>
>>>
>>> No. It is possible without computers, but is difficult. Certainly the
>>> reverted thrust is not easy to control, since you have a set of
>>> difficult tasks:
>>>
>>> point the engine in the right direction (opposite to the flight path)
>>
>> The spaceship had to point the thrust EXACTLY into the direction, where
>> it is flying, since even a few degrees off would make the ship rotate.
>> And that would be EXTREMELY dangerous.
>
> The thrust line has to pass through the craft's centre of gravity to
> avoid making the craft rotate. The direction of motion (which is
> ill-defined anyway) has nothing to do with it.

Actually no!

There are two components: inertia and gravity.

To decelerate the craft, the thrust should point directly into the 
direction, where the ships flies. (That's what I called 'direction of 
motion'.) This is caused by inertia, what is not altered by the lower 
gravity of Moon.

To compensate acceleration caused by gravity, the engine should generate 
a force in opposite direction (up), hence the thrust should point down.

This makes two accelerations that combine to the needed thrust, (what 
the crew had to direct properly).

Any minuscule error would cause a rotation or other unwanted features of 
the flight (like hitting the ground).

TH

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#359463

kefischer wrote:

>         In 1969, it might have had to be done
> manually, with the pilot watching to avoid craters or slopes, no
> electronics can do that, and the electronics then was not capable of all
> the inputs necessary.

A human pilot is an adaptive filter. A slow one. Without electronics 
(which are fast) flights are not possible nowadays. Disregard the flight 
mode, automatic or performed by a pilot. Among all the piano movers I 
know, you must be the most inexperienced one.

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#359466

On Sun, 2 Aug 2015 17:02:24 +0000 (UTC), wobbly <wobbly@dont-email.me>
wrote:

>kefischer wrote:
>
>>         In 1969, it might have had to be done
>> manually, with the pilot watching to avoid craters or slopes, no
>> electronics can do that, and the electronics then was not capable of all
>> the inputs necessary.
>
>A human pilot is an adaptive filter. A slow one. Without electronics 
>(which are fast) flights are not possible nowadays. 

         That's what Ben Rich claimed about his baby, 
but heck, anything with enough thrust and enough 
control surface _will_ fly, and can be flown by man;

https://www.youtube.com/watch?v=2Q24sjLUzF4

https://www.youtube.com/watch?v=Wf9Jfa5f1FA

https://www.youtube.com/watch?v=_iqqHAWJq_0

https://www.youtube.com/watch?v=sGWF7QTZZi0

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

       Scroll to 7:00

https://www.youtube.com/watch?v=Q7ohBpNCQ5s


       Now, change your name again, troll.


>Disregard the flight 
>mode, automatic or performed by a pilot. Among all the piano movers I 
>know, you must be the most inexperienced one.

      I  haven't moved a piano in 45 years.

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#359592

Am 02.08.2015 20:40, schrieb kefischer:
> On Sun, 2 Aug 2015 17:02:24 +0000 (UTC), wobbly<wobbly@dont-email.me>
> wrote:
>
>> kefischer wrote:
>>
>>>          In 1969, it might have had to be done
>>> manually, with the pilot watching to avoid craters or slopes, no
>>> electronics can do that, and the electronics then was not capable of all
>>> the inputs necessary.
>>
>> A human pilot is an adaptive filter. A slow one. Without electronics
>> (which are fast) flights are not possible nowadays.
>
>           That's what Ben Rich claimed about his baby,
> but heck, anything with enough thrust and enough
> control surface _will_ fly, and can be flown by man;

To slow down a lander from orbital velocity to zero velocity, while 
simultaneously land at a certain spot, that is fantastically difficult.


The pace was possibly about 5000 km/h in some kind of orbit at maybe 50 
km above ground.

The spaceship would circle around the Moon forever, if it is not slowed 
down.

Now you need to aim the engine into the right direction and fire it, to 
make the craft slow down.

Since you have no air to guide the lander, the direction of the lander 
needs to be manipulated into the right direction by pulses from 
additional engines or by directing the main engine.

Any miscalculation would cause a rotation.

That is something, you definitely don't like, since the main engine 
should point into the direction you are flying to. So, without 
prevention of such rotation you could not land.

To achieve this precision of flight is certainly a challenging task.


TH

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#359594

On Monday, August 3, 2015 at 9:32:52 PM UTC-5, Thomas Heger wrote:
> Am 02.08.2015 20:40, schrieb kefischer:
> > On Sun, 2 Aug 2015 17:02:24 +0000 (UTC), wobbly<wobbly@dont-email.me>
> > wrote:
> >
> >> kefischer wrote:
> >>
> >>>          In 1969, it might have had to be done
> >>> manually, with the pilot watching to avoid craters or slopes, no
> >>> electronics can do that, and the electronics then was not capable of all
> >>> the inputs necessary.
> >>
> >> A human pilot is an adaptive filter. A slow one. Without electronics
> >> (which are fast) flights are not possible nowadays.
> >
> >           That's what Ben Rich claimed about his baby,
> > but heck, anything with enough thrust and enough
> > control surface _will_ fly, and can be flown by man;
> 
> To slow down a lander from orbital velocity to zero velocity, while 
> simultaneously land at a certain spot, that is fantastically difficult.
> 
> 
> The pace was possibly about 5000 km/h in some kind of orbit at maybe 50 
> km above ground.
> 
> The spaceship would circle around the Moon forever, if it is not slowed 
> down.
> 
> Now you need to aim the engine into the right direction and fire it, to 
> make the craft slow down.
> 
> Since you have no air to guide the lander, the direction of the lander 
> needs to be manipulated into the right direction by pulses from 
> additional engines or by directing the main engine.
> 
> Any miscalculation would cause a rotation.
> 
> That is something, you definitely don't like, since the main engine 
> should point into the direction you are flying to. So, without 
> prevention of such rotation you could not land.
> 
> To achieve this precision of flight is certainly a challenging task.
> 
> 
> TH

Remember the moon lander hardly weighed anything.

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#359595

On Monday, August 3, 2015 at 9:32:52 PM UTC-5, Thomas Heger wrote:
> Am 02.08.2015 20:40, schrieb kefischer:
> > On Sun, 2 Aug 2015 17:02:24 +0000 (UTC), wobbly<wobbly@dont-email.me>
> > wrote:
> >
> >> kefischer wrote:
> >>
> >>>          In 1969, it might have had to be done
> >>> manually, with the pilot watching to avoid craters or slopes, no
> >>> electronics can do that, and the electronics then was not capable of all
> >>> the inputs necessary.
> >>
> >> A human pilot is an adaptive filter. A slow one. Without electronics
> >> (which are fast) flights are not possible nowadays.
> >
> >           That's what Ben Rich claimed about his baby,
> > but heck, anything with enough thrust and enough
> > control surface _will_ fly, and can be flown by man;
> 
> To slow down a lander from orbital velocity to zero velocity, while 
> simultaneously land at a certain spot, that is fantastically difficult.
> 
> 
> The pace was possibly about 5000 km/h in some kind of orbit at maybe 50 
> km above ground.
> 
> The spaceship would circle around the Moon forever, if it is not slowed 
> down.
> 
> Now you need to aim the engine into the right direction and fire it, to 
> make the craft slow down.
> 
> Since you have no air to guide the lander, the direction of the lander 
> needs to be manipulated into the right direction by pulses from 
> additional engines or by directing the main engine.
> 
> Any miscalculation would cause a rotation.
> 
> That is something, you definitely don't like, since the main engine 
> should point into the direction you are flying to. So, without 
> prevention of such rotation you could not land.
> 
> To achieve this precision of flight is certainly a challenging task.
> 
> 
> TH

I predict it will be 8 times harder than to land a plane on earth:>)

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#359621

Thomas Heger wrote:

> That is something, you definitely don't like, since the main engine
> should point into the direction you are flying to. So, without
> prevention of such rotation you could not land.

Quite difficult to land and control a quadcopter with a joystick, lots of 
buttons and a central processing unit. Ie 

http://www.quadhangar.com/how-to-correct-a-drifting-quadcopter/

I have no idea how they did it at that time, just by looking out of a 
window. I could not  do it, that's for sure.

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#359679

Am 04.08.2015 17:14, schrieb Bohuš Matuška:
> Thomas Heger wrote:
>
>> That is something, you definitely don't like, since the main engine
>> should point into the direction you are flying to. So, without
>> prevention of such rotation you could not land.
>
> Quite difficult to land and control a quadcopter with a joystick, lots of
> buttons and a central processing unit. Ie
>
> http://www.quadhangar.com/how-to-correct-a-drifting-quadcopter/
>
> I have no idea how they did it at that time, just by looking out of a
> window. I could not  do it, that's for sure.


"How a gyroscope guides a rocket"
https://www.youtube.com/watch?v=KToggTKa9Lk

http://www.npcap.ru/en/main-directions-of-activity/inertial-control-systems/creation-of-inertial-control-systems/development-of-inertial-measuring-devices-and-systems/

http://www.clavius.org/techsteer.html


TH

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#359699

Thomas Heger wrote:

> Am 04.08.2015 17:14, schrieb Bohuš Matuška:
>> Thomas Heger wrote:
>>
>>> That is something, you definitely don't like, since the main engine
>>> should point into the direction you are flying to. So, without
>>> prevention of such rotation you could not land.
>>
>> Quite difficult to land and control a quadcopter with a joystick, lots
>> of buttons and a central processing unit. Ie
>>
>> http://www.quadhangar.com/how-to-correct-a-drifting-quadcopter/
>>
>> I have no idea how they did it at that time, just by looking out of a
>> window. I could not  do it, that's for sure.
> 
> 
> "How a gyroscope guides a rocket"
> https://www.youtube.com/watch?v=KToggTKa9Lk
> 
> http://www.npcap.ru/en/main-directions-of-activity/inertial-control-
systems/creation-of-inertial-control-systems/development-of-inertial-
measuring-devices-and-systems/
> 
> http://www.clavius.org/techsteer.html

Didn't look, but quadcopter are felt with all kind of sensors as well, 
including 3d gyros, accelerometers and magnetic sensors.

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#359782

Am 05.08.2015 15:35, schrieb Bohuš Matuška:
> Thomas Heger wrote:
>
>> Am 04.08.2015 17:14, schrieb Bohuš Matuška:
>>> Thomas Heger wrote:
>>>
>>>> That is something, you definitely don't like, since the main engine
>>>> should point into the direction you are flying to. So, without
>>>> prevention of such rotation you could not land.
>>>
>>> Quite difficult to land and control a quadcopter with a joystick, lots
>>> of buttons and a central processing unit. Ie
>>>
>>> http://www.quadhangar.com/how-to-correct-a-drifting-quadcopter/
>>>
>>> I have no idea how they did it at that time, just by looking out of a
>>> window. I could not  do it, that's for sure.
>>
>>
>> "How a gyroscope guides a rocket"
>> https://www.youtube.com/watch?v=KToggTKa9Lk
>>
>> http://www.npcap.ru/en/main-directions-of-activity/inertial-control-
> systems/creation-of-inertial-control-systems/development-of-inertial-
> measuring-devices-and-systems/
>>
>> http://www.clavius.org/techsteer.html
>
> Didn't look, but quadcopter are felt with all kind of sensors as well,
> including 3d gyros, accelerometers and magnetic sensors.
>

Such model copters are actually a good example for the problems of rocketry.

The first landers had  gyroscopes to guide the crafts.

First use of gyroscopes was in the rocket 'V2', build by Germans under 
direction of Wernher von Braun. He was also the head of  the 'Apollo' 
program of the NASA, hence we can safely assume, he would use gyroscopes 
if necessary.

Those Apollo landers had only one engine, hence the deceleration is 
similar to balance a broom-stick on an ascending rocket. (certainly 
difficult)

The other problems are:

a LOT of fuel is required

the velocity should be zero (vertically and horizontal)  exactly at 
surface level (not a few meters above or below).

the landing zone has influence on the subsequent rendezvous, hence it is 
important to manage to land at a certain spot.

All of the tasks are interwoven, since e.g. corrections would require 
time and that would make the lander land somewhere else. It would also 
consume fuel.

To figure out the various consequences of a certain activity would 
require a fast calculator, who could do such calculations several times 
per second.


TH

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#359784

On Wednesday, August 5, 2015 at 11:42:45 PM UTC-5, Thomas Heger wrote:
> Am 05.08.2015 15:35, schrieb Bohuš Matuška:
> > Thomas Heger wrote:
> >
> >> Am 04.08.2015 17:14, schrieb Bohuš Matuška:
> >>> Thomas Heger wrote:
> >>>
> >>>> That is something, you definitely don't like, since the main engine
> >>>> should point into the direction you are flying to. So, without
> >>>> prevention of such rotation you could not land.
> >>>
> >>> Quite difficult to land and control a quadcopter with a joystick, lots
> >>> of buttons and a central processing unit. Ie
> >>>
> >>> http://www.quadhangar.com/how-to-correct-a-drifting-quadcopter/
> >>>
> >>> I have no idea how they did it at that time, just by looking out of a
> >>> window. I could not  do it, that's for sure.
> >>
> >>
> >> "How a gyroscope guides a rocket"
> >> https://www.youtube.com/watch?v=KToggTKa9Lk
> >>
> >> http://www.npcap.ru/en/main-directions-of-activity/inertial-control-
> > systems/creation-of-inertial-control-systems/development-of-inertial-
> > measuring-devices-and-systems/
> >>
> >> http://www.clavius.org/techsteer.html
> >
> > Didn't look, but quadcopter are felt with all kind of sensors as well,
> > including 3d gyros, accelerometers and magnetic sensors.
> >
> 
> Such model copters are actually a good example for the problems of rocketry.
> 
> The first landers had  gyroscopes to guide the crafts.
> 
> First use of gyroscopes was in the rocket 'V2', build by Germans under 
> direction of Wernher von Braun. He was also the head of  the 'Apollo' 
> program of the NASA, hence we can safely assume, he would use gyroscopes 
> if necessary.
> 
> Those Apollo landers had only one engine, hence the deceleration is 
> similar to balance a broom-stick on an ascending rocket. (certainly 
> difficult)
> 
> The other problems are:
> 
> a LOT of fuel is required
> 
> the velocity should be zero (vertically and horizontal)  exactly at 
> surface level (not a few meters above or below).
> 
> the landing zone has influence on the subsequent rendezvous, hence it is 
> important to manage to land at a certain spot.
> 
> All of the tasks are interwoven, since e.g. corrections would require 
> time and that would make the lander land somewhere else. It would also 
> consume fuel.
> 
> To figure out the various consequences of a certain activity would 
> require a fast calculator, who could do such calculations several times 
> per second.
> 
> 
> TH

Here's a moon nerd joke.  If landing on the moon is too harmful for mankind then why don't we just land on its' dark side?

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#359880

Am 06.08.2015 07:24, schrieb John Gogo:
..
>> the velocity should be zero (vertically and horizontal)  exactly at
>> surface level (not a few meters above or below).
>>
>> the landing zone has influence on the subsequent rendezvous, hence it is
>> important to manage to land at a certain spot.
>>
>> All of the tasks are interwoven, since e.g. corrections would require
>> time and that would make the lander land somewhere else. It would also
>> consume fuel.
>>
>> To figure out the various consequences of a certain activity would
>> require a fast calculator, who could do such calculations several times
>> per second.
>>
>>
>> TH
>
> Here's a moon nerd joke.  If landing on the moon is too harmful for mankind then why don't we just land on its' dark side?

Would be too dark. And it's actually quite cold there.

After sunrise, that would change very quickly and it gets really hot. 
Also sunlight is VERY bright there and completely unfiltered.

So, you could chose between being boiled or getting frozen. And you 
could chose between pitch black nothing and blazing brightness.

TH

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#359883

On Fri, 07 Aug 2015 08:09:06 +0200, Thomas Heger <ttt_heg@web.de> wrote:

>Am 06.08.2015 07:24, schrieb John Gogo:
>..
>>> the velocity should be zero (vertically and horizontal)  exactly at
>>> surface level (not a few meters above or below).
>>>
>>> the landing zone has influence on the subsequent rendezvous, hence it is
>>> important to manage to land at a certain spot.
>>>
>>> All of the tasks are interwoven, since e.g. corrections would require
>>> time and that would make the lander land somewhere else. It would also
>>> consume fuel.
>>>
>>> To figure out the various consequences of a certain activity would
>>> require a fast calculator, who could do such calculations several times
>>> per second.
>>>
>>>
>>> TH
>>
>> Here's a moon nerd joke.  If landing on the moon is too harmful for mankind then why don't we just land on its' dark side?
>
>Would be too dark. And it's actually quite cold there.
>
>After sunrise, that would change very quickly and it gets really hot. 
>Also sunlight is VERY bright there and completely unfiltered.
>
>So, you could chose between being boiled or getting frozen. And you 
>could chose between pitch black nothing and blazing brightness.
>
>TH

        There is no "dark side", there is a "day side"
and a "night side".

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#359892

Am 07.08.2015 08:41, schrieb kefischer:
>>> Here's a moon nerd joke.  If landing on the moon is too harmful for mankind then why don't we just land on its' dark side?
>> >
>> >Would be too dark. And it's actually quite cold there.
>> >
>> >After sunrise, that would change very quickly and it gets really hot.
>> >Also sunlight is VERY bright there and completely unfiltered.
>> >
>> >So, you could chose between being boiled or getting frozen. And you
>> >could chose between pitch black nothing and blazing brightness.
>> >
>> >TH
>          There is no "dark side", there is a "day side"
> and a "night side".
>



You certainly have noticed, that 'dark' was used as synonym for 'night'.

Well, maybe English more strict in such cases (compared to German).

But a 'day' on moon is not really a day (more month), hence I would like 
to call the dark side 'dark side'. (if you allow)


TH

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#359894

On 08/07/2015 08:41 AM, kefischer wrote:
> 
>         There is no "dark side", there is a "day side"
> and a "night side".

Day side is supposed to be bright,
same as night side to is supposed to be dark.

Physically, dark/bright side is even more appropriate,
referring to physical attributes,
than day/night, that is more human and social centric.

-- 
Poutnik ( the Czech word for a wanderer )

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#359901

On Fri, 07 Aug 2015 10:29:50 +0200, Poutnik <Poutnik4NNTP@gmail.com>
wrote:

>On 08/07/2015 08:41 AM, kefischer wrote:
>> 
>>         There is no "dark side", there is a "day side"
>> and a "night side".
>
>Day side is supposed to be bright,
>same as night side to is supposed to be dark.
>
>Physically, dark/bright side is even more appropriate,
>referring to physical attributes,
>than day/night, that is more human and social centric.

        Nonsense, the moon rotates about 13 times
a year, the words dark and light do not denote
a changing condition in light, day and night does.

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#359903

On 08/07/2015 12:21 PM, kefischer wrote:
> On Fri, 07 Aug 2015 10:29:50 +0200, Poutnik <Poutnik4NNTP@gmail.com>
> wrote:
> 
>> On 08/07/2015 08:41 AM, kefischer wrote:
>>>
>>>         There is no "dark side", there is a "day side"
>>> and a "night side".
>>
>> Day side is supposed to be bright,
>> same as night side to is supposed to be dark.
>>
>> Physically, dark/bright side is even more appropriate,
>> referring to physical attributes,
>> than day/night, that is more human and social centric.
> 
>         Nonsense, the moon rotates about 13 times
> a year, the words dark and light do not denote
> a changing condition in light, day and night does.
> 

Dark and bright is not black and white,
they do denote light conditions
as amount of light reflected.

Day and night are human centric terms.

-- 
Poutnik ( the Czech word for a wanderer )

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#359908

Poutnik wrote:

>>         Nonsense, the moon rotates about 13 times
>> a year, the words dark and light do not denote a changing condition in
>> light, day and night does.
>> 
>> 
> Dark and bright is not black and white, they do denote light conditions
> as amount of light reflected.
> 
> Day and night are human centric terms.

Dark and bright side of the Moon, doesn't mean those parts or regions are 
always in dark or light. Kefisher is stronger than you in dvergent matter.

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