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Author Topic: Moon Walkers.  (Read 88064 times)

tinman

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Re: Moon Walkers.
« Reply #15 on: January 22, 2016, 11:42:09 PM »
http://lroc.sese.asu.edu/posts/379

The total cost of the mission is reported as US$583 million, of which $504 million pertains to the main LRO probe and $79 million to the LCROSS satellite.
Are we to believe that NASA spent 583 million dollars on a probe to take pictures of the moons surface,and forgot to put a high resolution camera on board that could take clear pictures of the lunar landers on the moon? ::) . Is that the best there is PW ?. Be honest with your self--if you were not told that the picture was of the lunar lander module,would you know what it was. Could i post some blurry pictures like that one of some object,and then have you tell me what it is?.

Here is a satellite picture from digital globe's satellite,from around 400km,-->and through the earths atmosphere.


Brad

scratchrobot

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Re: Moon Walkers.
« Reply #16 on: January 23, 2016, 12:11:23 AM »
Together we could build a rover with pulse motors powered by radiant energy  :P 

MileHigh

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Re: Moon Walkers.
« Reply #17 on: January 23, 2016, 12:11:24 AM »
The total cost of the mission is reported as US$583 million, of which $504 million pertains to the main LRO probe and $79 million to the LCROSS satellite.
Are we to believe that NASA spent 583 million dollars on a probe to take pictures of the moons surface,and forgot to put a high resolution camera on board that could take clear pictures of the lunar landers on the moon? ::) . Is that the best there is PW ?. Be honest with your self--if you were not told that the picture was of the lunar lander module,would you know what it was. Could i post some blurry pictures like that one of some object,and then have you tell me what it is?.

Here is a satellite picture from digital globe's satellite,from around 400km,-->and through the earths atmosphere.


Brad

This is just a classic example of failed logic and failure to think past one step.  TK already responded to this elsewhere.

"A satellite in orbit around the moon must have equal imaging resolution to a satellite in orbit around Earth."

Says who?

Duh!  Doh!

Who said that was in the "rule book?"   You, Brad?  You just invented that rule out of thin air because you don't want to think?

There are thousands of satellites in orbit around Earth with all sorts of different optical systems, imagers, design goals, budgets, weight restrictions, amounts of expendable fuel, and so on and so on.

So who the hell are you to "force your expectations of a certain optical and imaging performance" on a satellite in orbit around the moon that you probably know next to nothing about?

It's just beyond ridiculous.  It's like you want to force your "vision" of what the satellite *should* be like so that "your declarative statement makes sense."   You want that satellite to have a large 5-kilogram very powerful telescopic lens mounted on it and for all you know the optical team was given design constraints of 75 grams total for the mass of the lens and it had to fit into a very small space.

Yes, I pushed this one to show you how absolutely ridiculous your statement was to compare two completely different satellites orbiting around two different heavenly bodies with two different budgets and two different sets of design goals and two different sets of constraints.  And like a bull in a China ship you just blast through all of that and make a "declarative statement."  And you think that you can design a moon rover on the cheap like it would be a piece of cake when you think like that?

Joe is an Old Salt.
Salt dissolves in water.
Therefore, Joe dissolves in water.

tinman

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Re: Moon Walkers.
« Reply #18 on: January 23, 2016, 12:32:32 AM »
This is just a classic example of failed logic and failure to think past one step.  TK already responded to this elsewhere.

"

Says who?

Duh!  Doh!

Who said that was in the "rule book?"   You, Brad?  You just invented that rule out of thin air because you don't want to think?

There are thousands of satellites in orbit around Earth with all sorts of different optical systems, imagers, design goals, budgets, weight restrictions, amounts of expendable fuel, and so on and so on.

So the hell are you to "force your expectations of a certain optical and imaging performance" on a satellite in orbit around the moon that you probably know next to nothing about?

It's just beyond ridiculous.  It's like you want to force your "vision" of what the satellite *should* be like so that "your declarative statement makes sense."   You want that satellite to have a large 5-kilogram very powerful telescopic lens mounted on it and for all you know the optical team was given design constraints of 75 grams total for the mass of the lens and it had to fit into a very small space.

 And like a bull in a China ship you just blast through all of that and make a "declarative statement."  And you think that you can design a moon rover on the cheap like it would be a piece of cake when you think like that?

Joe is an Old Salt.
Salt dissolves in water.
Therefore, Joe dissolves in water.

Quote
A satellite in orbit around the moon must have equal imaging resolution to a satellite in orbit around Earth."

Once again MH,it is you that fails to see the big picture here. Now what brainless bunch of idiot's would send an imagery satellite to the moon that was not capable of taking clear high res picture's?. Some times you just do not think first,as your need to believe in something out weighs your own common sense.
Quote
Yes, I pushed this one to show you how absolutely ridiculous your statement was to compare two completely different satellites orbiting around two different heavenly bodies with two different budgets and two different sets of design goals and two different sets of constraints.


Perhaps you had better go read up a little on both satellites,and see which had the larger budget,and what was the goal for both satellites. Then i would like you to post 1 (just 1) nice clear picture of any equipment left behind on the moon by the moon walkers-->lets see you do that.

You are way to bias MH to even be commenting on this thread,as if it was any one else making a huge claim like this,and presented the evidence like NASA have,you would laugh in there face.

Show us some third party proof MH,that man went to the moon-->and not just word's MH,as we all know they mean nothing when it comes to scientific evidence.


Brad

picowatt

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Re: Moon Walkers.
« Reply #19 on: January 23, 2016, 02:01:38 AM »
The total cost of the mission is reported as US$583 million, of which $504 million pertains to the main LRO probe and $79 million to the LCROSS satellite.
Are we to believe that NASA spent 583 million dollars on a probe to take pictures of the moons surface,and forgot to put a high resolution camera on board that could take clear pictures of the lunar landers on the moon? ::) . Is that the best there is PW ?. Be honest with your self--if you were not told that the picture was of the lunar lander module,would you know what it was. Could i post some blurry pictures like that one of some object,and then have you tell me what it is?.

Here is a satellite picture from digital globe's satellite,from around 400km,-->and through the earths atmosphere.


Brad

Tinman,

The LRO can do 50cm/pixel as opposed to the 30cm/pixel image you post here.  Keep in mind that when looking at the LEM in the LROC images, you are looking at an object only slightly larger than the baggage carts seen in the airport photo you posted. 

The LRO has been another notable accomplishment, with more data returned than all other planetary missions combined.  Having both continued to perform beyond their original mission lifetimes, the LRO and Mars Opportunity Rover have received continued funding thru 2016.   

What is the resolution of the images being returned from the Australian lunar orbiter?

PW
« Last Edit: January 23, 2016, 08:25:23 AM by picowatt »

picowatt

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Re: Moon Walkers.
« Reply #20 on: January 23, 2016, 05:02:16 AM »
Check out these additional recent missions by NASA.

Also consider that the scientific data collected by these missions is available to scientists and researchers all over the world.   

https://en.wikipedia.org/wiki/THEMIS
https://en.wikipedia.org/wiki/Lunar_Atmosphere_and_Dust_Environment_Explorer
https://en.wikipedia.org/wiki/International_Lunar_Network

Space exploration is expensive and complicated. 

Imagine the cascade of design and cost issues that arise just from doubling the visible camera resolution.  Doubling the resolution would quadruple the number of pixels.  Given the same frame rate, that results in having to increase the data transmission rate by a factor of four.  The end result will likely more than quadruple the power requirement for the camera and the transmitter power required for the additional bandwidth.  This necessitates an increase of the size of the solar arrays which will add more weight to the orbiter.

In order to not sacrifice image quality and the S/N ratio, were gong to want to maintain the same pixel size as used at the lower resolution which means the sensor will be physically larger.  As well, to maintain the same S/N we will need to maintain the same lens speed (ratio of aperture to focal length).  Because the field of view requirements are likely dictated by orbital mechanics and the desired per pass coverage, it will also be necessary to maintain the same FOV.  In order to maintain the same lens speed and FOV using the larger and higher resolution sensor, the size of the lenses used in the optics will need to be made larger.  This will also add additional weight to the orbiter.

Because of the additional weight, orbital insertion and station keeping will require more fuel.  This means that unless one is willing to shorten the mission lifetime, extra fuel must be carried which will again add additional weight. 

Having to carry the weight of the additional fuel will also require having to burn even more fuel for at least the orbital insertion phase of the mission, so again, even a bit more fuel will have to be carried. 

Now we have to increase the size of the fuel tanks, which adds more weight and again requires more fuel.

Eventually we arrive at a compromise and now have a larger and heavier orbiter.

So, now we need to look at the launch platform and see what that additional size and weight is going to cost.  From there its about the same, more weight, more fuel, etc. 

Also consider that there are additional sensors on the orbiter.  Every group related to a given sensor wants theirs to receive a degree of priority, more bandwidth, more power, etc.  Imagine a meeting where engineers or department heads are begging for a few additional milliwatts or kilobytes of bandwidth.

Making anything but minor changes requires a complete review of how those modifications will affect everything from the orbiter's weight, power, fuel requirements, launch costs and mission life. 

In the end there are often compromises, but NASA does what it can with the budget it has.

PW

         

picowatt

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Re: Moon Walkers.
« Reply #21 on: January 23, 2016, 05:12:08 AM »

MileHigh

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Re: Moon Walkers.
« Reply #22 on: January 23, 2016, 06:26:59 AM »
Brad:

I will tell you up front that I never looked up the capabilities of the imaging systems on either satellite.  I was just reacting to what you stated.

I will pose the question to you:  Before you made your statement did you look up the capabilities of the imaging systems on the two satellites?

Beyond that, PW like usual made astute comments about the meters per pixel for the two imaging systems.  I also read his link about how the LRO dipped quite unusually low before they did the orbital correction and that gave them an opportunity to try to image one of the landing sites with better resolution.  I also skimmed through his earlier link with a 10-page scientific explanation and investigation into the Van Allen radiation belts.

PW also correctly pointed out how your image of the airport tarmac with the airplanes was of an outrageously larger object as compared to the LEM on the moon and the image comparison for all practical intents and purposes wasn't even valid.  I suppose that didn't occur to you.

My gut feel is telling me you did no research and just made a ridiculous inappropriate comparison to make a point.  In your mind you thought that was valid.  Let's see if you will answer the question.

My gut feel is also telling me that the imaging system on the LRO is a relatively wide-field camera system for scanning the entire moon's surface and just for fun the team tried to image the Apollo landing site even though the system was not designed to do that.

MileHigh

picowatt

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Re: Moon Walkers.
« Reply #23 on: January 23, 2016, 07:10:08 AM »
MH,

The LRO has two 50cm/pixel at 50km narrow field cameras and a separate "pushbroom" wide field sensor/camera (as well as several other sensors).

It might be interesting to see what the LRO team is willing to do later on regarding the orbital height as the LRO nears its end of life (fuel exhaustion).  Maybe they will try a closer pass of an Apollo site...

If you read the LADEE link in my earlier post, you will see that they intentionally impacted that orbiter onto the far side of the moon at the end of its life so as to prevent any possible damage to historical landing sites such as Apollo, Luna, etc.

The LRO and other missions I linked to openly provide data to researchers around the world.

I never complain about any of my tax dollars going to NASA.

PW

Added:  Read the links reposted below when you get the time, they are missions that most people probably never heard of that did a lot of interesting science.

https://en.wikipedia.org/wiki/THEMIS
https://en.wikipedia.org/wiki/Lunar_Atmosphere_and_Dust_Environment_Explorer

TinselKoala

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Re: Moon Walkers.
« Reply #24 on: January 23, 2016, 09:42:39 AM »
Fake, of course. Right, TinMan?


ramset

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Re: Moon Walkers.
« Reply #25 on: January 23, 2016, 10:54:35 AM »
Tinsel
can a terrestrial observatory get good images of these things ?

could the Hubble ?

tinman

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Re: Moon Walkers.
« Reply #26 on: January 23, 2016, 12:37:59 PM »
Tinman,

  Keep in mind that when looking at the LEM in the LROC images, you are looking at an object only slightly larger than the baggage carts seen in the airport photo you posted. 

The LRO has been another notable accomplishment, with more data returned than all other planetary missions combined.  Having both continued to perform beyond their original mission lifetimes, the LRO and Mars Opportunity Rover have received continued funding thru 2016.   

What is the resolution of the images being returned from the Australian lunar orbiter?

PW

Quote
The LRO can do 50cm/pixel as opposed to the 30cm/pixel image you post here.

Agreed-no problem there.
But lets not forget the distance difference between the two as well,and also the fact that one was shot through the earth's atmosphere,were as the other will experience no atmospheric disturbance or distortions at all. 

LRO distance from moon surface is 25km @ 50cm/pixels-->no atmospheric interference.
World view satellite distance from earth surface + atmospheric interference is 770km @ 30cm/pixels
It is not hard to work out which one should return the better/clearer images.


Brad

tinman

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Re: Moon Walkers.
« Reply #27 on: January 23, 2016, 01:12:08 PM »
Fake, of course. Right, TinMan?

As real as the next image TK.
As you can see,i have been to the moon as well :D
After all,there is a picture of it.

tinman

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Re: Moon Walkers.
« Reply #28 on: January 23, 2016, 01:23:37 PM »
Brad:

I will tell you up front that I never looked up the capabilities of the imaging systems on either satellite.  I was just reacting to what you stated.



Beyond that, PW like usual made astute comments about the meters per pixel for the two imaging systems.    I also skimmed through his earlier link with a 10-page scientific explanation and investigation into the Van Allen radiation belts.

PW also correctly pointed out how your image of the airport tarmac with the airplanes was of an outrageously larger object as compared to the LEM on the moon and the image comparison for all practical intents and purposes wasn't even valid.  I suppose that didn't occur to you.

My gut feel is telling me you did no research and just made a ridiculous inappropriate comparison to make a point.  In your mind you thought that was valid.  Let's see if you will answer the question.

My gut feel is also telling me that the imaging system on the LRO is a relatively wide-field camera system for scanning the entire moon's surface and just for fun the team tried to image the Apollo landing site even though the system was not designed to do that.

MileHigh

Quote
I will pose the question to you:  Before you made your statement did you look up the capabilities of the imaging systems on the two satellites?

Yes i did MH,although i had the orbit distance wrong with the world view satellite,as it turned out to be in a much higher orbit than the 400 odd km i stated.
As i said to PW-->
LRO distance from moon surface is 25km @ 50cm/pixels-->no atmospheric interference.
World view satellite distance from earth surface + atmospheric interference is 770km @ 30cm/pixels
It is not hard to work out which one should return the better/clearer images.

Quote
I also read his link about how the LRO dipped quite unusually low before they did the orbital correction and that gave them an opportunity to try to image one of the landing sites with better resolution.

Yes,down to 25km at one stage. But if you look at the image taken from 50km,and then the one that was suppose to be at 25km,they are the same image with the same resolution. ???

So you tell me MH-->which !should! give the better/clearer image.

Brad



tinman

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Re: Moon Walkers.
« Reply #29 on: January 23, 2016, 02:01:24 PM »
Check out these additional recent missions by NASA.

Also consider that the scientific data collected by these missions is available to scientists and researchers all over the world.   

https://en.wikipedia.org/wiki/THEMIS
https://en.wikipedia.org/wiki/Lunar_Atmosphere_and_Dust_Environment_Explorer
https://en.wikipedia.org/wiki/International_Lunar_Network

Space exploration is expensive and complicated. 

Imagine the cascade of design and cost issues that arise just from doubling the visible camera resolution.  Doubling the resolution would quadruple the number of pixels.  Given the same frame rate, that results in having to increase the data transmission rate by a factor of four.  The end result will likely more than quadruple the power requirement for the camera and the transmitter power required for the additional bandwidth.  This necessitates an increase of the size of the solar arrays which will add more weight to the orbiter.

In order to not sacrifice image quality and the S/N ratio, were gong to want to maintain the same pixel size as used at the lower resolution which means the sensor will be physically larger.  As well, to maintain the same S/N we will need to maintain the same lens speed (ratio of aperture to focal length).  Because the field of view requirements are likely dictated by orbital mechanics and the desired per pass coverage, it will also be necessary to maintain the same FOV.  In order to maintain the same lens speed and FOV using the larger and higher resolution sensor, the size of the lenses used in the optics will need to be made larger.  This will also add additional weight to the orbiter.

Because of the additional weight, orbital insertion and station keeping will require more fuel.  This means that unless one is willing to shorten the mission lifetime, extra fuel must be carried which will again add additional weight. 

Having to carry the weight of the additional fuel will also require having to burn even more fuel for at least the orbital insertion phase of the mission, so again, even a bit more fuel will have to be carried. 

Now we have to increase the size of the fuel tanks, which adds more weight and again requires more fuel.

Eventually we arrive at a compromise and now have a larger and heavier orbiter.

So, now we need to look at the launch platform and see what that additional size and weight is going to cost.  From there its about the same, more weight, more fuel, etc. 

Also consider that there are additional sensors on the orbiter.  Every group related to a given sensor wants theirs to receive a degree of priority, more bandwidth, more power, etc.  Imagine a meeting where engineers or department heads are begging for a few additional milliwatts or kilobytes of bandwidth.

Making anything but minor changes requires a complete review of how those modifications will affect everything from the orbiter's weight, power, fuel requirements, launch costs and mission life. 

In the end there are often compromises, but NASA does what it can with the budget it has.

PW

       

Well apparently there is no problem with the Mars Reconnaissance Orbiter launched on August 12, 2005, . The picture is of a track left after a boulder rolled down a hill !apparently!. The boulder is said to be about only 3.5 meters wide.

Out of every satellite and telescope ever launched,not one has the capability to take a clear shot of any of the equipment left behind on the moon by the moon walkers--not one. Even other countries that have sent satellites and rovers to the moon have never taken one clear picture of any of the equipment left behind by the U.S.