FAR SIDE OF THE MOON

[bknight]

Perhaps Father Ted will be able to help us. The magic start at the 30 second mark. But do watch the whole clip!

 

I don't think tarkus gets it

[ka9q]

Black Brown Red Orange Yellow Green Blue Violet Green White.

No, it's Black Brown Red Orange Yellow Green Blue Violet *Gray* White.

Now I have a little ditty that acts as an memory aid for that but it is so NON PC I couldn't repeat it on here.

I suspect I learned the same ditty you did. Begins with "Bad boys", right?

The first three bands are the number 4th band is the multiplier you can sometimes have 5th the tolerance followed by the 6th temp co-efficient.

Only the high precision resistors. Most have two bands for the mantissa. E.g., brown-black-red
is 1 k ohm and yellow-violet-orange is 47 k ohm. The fourth band is the tolerance; none = 20%, silver = 10%, gold = 5%. A temp coefficient band must be really rare; I've never seen one.

[ka9q]

Not quite the same, but there's a video or two going around showing local youth listening to AM radio broadcasts from a tower by jamming a dry weed against the metal.

You mean the tower that's the antenna?

AM radio stations use an entire tower as an antenna element. (Some have several towers in a line, driven in such a way that they produce a directional beam.) They are insulated from ground and fed with up to 50 kW, so you can be seriously burned just by touching it. I wouldn't be surprised if the dry weed in question burst into flames after a while.

[bknight]

Black Brown Red Orange Yellow Green Blue Violet Green White.

No, it's Black Brown Red Orange Yellow Green Blue Violet *Gray* White.

Now I have a little ditty that acts as an memory aid for that but it is so NON PC I couldn't repeat it on here.

I suspect I learned the same ditty you did. Begins with "Bad boys", right?

The first three bands are the number 4th band is the multiplier you can sometimes have 5th the tolerance followed by the 6th temp co-efficient.

Only the high precision resistors. Most have two bands for the mantissa. E.g., brown-black-red
is 1 k ohm and yellow-violet-orange is 47 k ohm. The fourth band is the tolerance; none = 20%, silver = 10%, gold = 5%. A temp coefficient band must be really rare; I've never seen one.

I remember an electronic lab where we fabricated black boxes to do certain tasks.  The resister code was posted on the wall, but I don't remember any saying that went with I.  I do suffer from CRS.

[Bryanpoprobson]

No, it's Black Brown Red Orange Yellow Green Blue Violet *Gray* White.

gray* ? I speak the real version of English, do you mean "Grey?" 

I'm sorry I couldn't resist, you are quite correct of course.

PS. My version was even less PC than that.

[nomuse]

Not quite the same, but there's a video or two going around showing local youth listening to AM radio broadcasts from a tower by jamming a dry weed against the metal.

You mean the tower that's the antenna?

AM radio stations use an entire tower as an antenna element. (Some have several towers in a line, driven in such a way that they produce a directional beam.) They are insulated from ground and fed with up to 50 kW, so you can be seriously burned just by touching it. I wouldn't be surprised if the dry weed in question burst into flames after a while.

It most certainly did. As far as I can figure out, the twig is grounded through their bodies (they comment on the video about feeling a shock, which becomes outright pain as the stick gets too hot to hold.) Actually, I suspect the twig in questing is WET, not dry -- that thermal expansion of the wet fibre and/or water evaporating off is what is pushing the air to make audible sound from the AM. And once the water content gets too low, it carbonizes, the conductivity goes WAY up, and all sorts of exciting things start to happen...

[bknight]

No, it's Black Brown Red Orange Yellow Green Blue Violet *Gray* White.

gray* ? I speak the real version of English, do you mean "Grey?" 

I'm sorry I couldn't resist, you are quite correct of course.

PS. My version was even less PC than that.

Of course this all depends on your definition of real English!

[Jason Thompson]

As tarkus is back posting on other threads I'm just going to reiterate my earlier question for him: how big will earth appear from 800,000 km?

[bknight]

As tarkus is back posting on other threads I'm just going to reiterate my earlier question for him: how big will earth appear from 800,000 km?

He appears to be gish galloping through many "anomalies.

[JayUtah]

He appears to be gish galloping through many "anomalies.

Yes, he seems to have found Eric Hufschmid's stuff and has wrongly believed Eric is some kind of expert.

[bknight]

He appears to be gish galloping through many "anomalies.

Yes, he seems to have found Eric Hufschmid's stuff and has wrongly believed Eric is some kind of expert.

That's what he was  doing  in his recent absence finding other people to mimic

[tarkus]

After carefully examining both sectors identified for you, I must say that was a good try, but failed. If what you intend is to find matches, please point out identical sectors, not only similar. 

Examine them again, preferably AFTER you have been to your optician to have your eyesight checked.

The craters in the red box are Ostwald, Ibn Firnas and Ardeshir. Ostwald is the crater with the smaller crater lying on it's rim- crater Recht (Ostwald is the topmost of the trio in the left hand image and on the bottom right in the right hand image.

I admit that there is some similarity between the sectors that you point out, although the craters surrounding these selections do not match ... but to say that both images (Apollo and LRO) are equivalent, should you point out at least one full sector, portion that goes from north to south, but you do not because you have not found anything more than 2-3 doubtful craters, and thus believes he has disproved something.

[JayUtah]

I admit that there is some similarity between the sectors that you point out, although the craters surrounding these selections do not match

Yes they do.  As has been mentioned several times to you, the far side of the Moon is known geology.  All those craters and regions have actual names and are very familiar even to amateur astronomers.  Your inability to rectify the distortion caused by the spherical shape is your own problem.

... but to say that both images (Apollo and LRO) are equivalent, should you point out at least one full sector, portion that goes from north to south

Shifting the goalposts.  Further, you wrongly assume these photos have the same orientation, such that such a "sector" could arise.  Still more evidence of your copious ignorance and utter incompetence at spatial reasoning.

...but you do not because you have not found anything more than 2-3 doubtful craters, and thus believes he has disproved something.

Your claim has been thoroughly rebutted and you know it.  That's why you have to come back and invent new rules for the comparison.

[tarkus]

Meh.

Unless my brain has gone to porridge what with these hot days we've been having, lens length is only material in how wide the field of view is. It matters for "Earth should look bigger" (that is, take up more of the frame in some photograph in question) but not for any comparison of visual diameters. Aka "The Moon should look bigger than the Earth."

For that question, it is only about location, location, location. Camera matters not. It's all in the geometry.

Hi nomuse, yes you are right, if we are just considering relative sizes then cameras and focal lengths and focal points are not relevant.  You just need to compare Moon/Earth size ratios and relative distances to observer as I did in a couple of earlier posts and others have done in diagrams and photos.

To confirm 'in the field' the effect of focal length on relative size I went out this morning and shot the following:

70mm focal length, with the 'Moon' (small ruler) one metre from the 'Earth' (the big ruler).  The camera is positioned 6 metres further on from the 'Moon'. The relative distances match the Earth/Moon/DSCOVR positions



Using 10cm on the small ruler for the Moon diameter and 40cm on the big ruler for the Earth (sizes chosen to keep things simple) and after resizing and cropping to an image width of 1000 pixels we get:
Moon (168px) / Earth (498px) = Moon/Earth ratio of 0.337 = 33.7%.

Now at 100mm focal length (all objects and the camera unmoved):


Moon (152px) / Earth (454px) = Moon/Earth ratio of 0.335 = 33.5%.

200mm:


Moon (162px) / Earth (484px) = Moon/Earth ratio of 0.335 = 33.5%.

And finally 300mm:


Moon (236px) / Earth (710px) = Moon/Earth ratio of 0.332 = 33.2%.

Conclusion 1: So allowing for lens distortion through the zoom range, and margin of error from measuring the pixel lengths, the Moon and Earth ratio has remained constant regardless of focal length.

Now the effect of moving the camera forwards. We already have the 6m ratio at around 33% regardless of focal length.
So with camera at 3m from the Moon (at 70mm focal length):



Moon (171px) / Earth (423px) = Moon/Earth ratio of 0.404 = 40.4%.
So Moon has increased in size relative to Earth by moving nearer.

And with camera at 1m from the Moon (70mm):



Moon (353px) / Earth (473px) = Moon/Earth ratio of 0.746 = 74.6%.
The Moon has again increased substantially relative to the Earth.

Conclusion 2: Changing the relative distances between objects and observer changes the relative size of the objects.

You make the same mistake as the rest of their comrades in astrophotography these tricks with the focus not work, you can not make the planet that is in the background looks larger than the one in the foreground, and much unless a spacecraft is able to perform such tricks, as well, why do such a thing? only is a poor way to not accept the obvious: that animation is horrifying.

NASA has made other trash animated gif, in this case "Pluto" ... the New Horizons had focus problems during their journey? always it looks blurry !!!

[JayUtah]

You make the same mistake as the rest of their comrades in astrophotography these tricks with the focus not work

No, once again you fail to understand the problem at all.  The ratio of the distances between the photographer and various objects in the field of view is what determines, along with focal length, the apparent sizes.  You defeated that by cropping and resizing the image to make some selected object the same size in the frame, and then defeated it by studying only one effect in isolation.  You simply don't know what you're doing, and you're fudging the evidence to make it come out the way you need it to.

What's really sad is that in order to have staged this experiment, you had to have seen the effects we referred to.  But you've deliberately arranged for data points that appear to prove your point in defiance of that.