Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Andrew K Fletcher on 10/01/2012 00:49:23
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Approx Location: ARISTARCHUS
http://www.lpl.arizona.edu/sic/journal/pdfs/121_Hartmann_CommLPL_1968.pdf
Intriguing flickering lights from an area approximately 9 o'clock which corresponds to ARISTARCHUS location using Google Earth.
What you think?
Andrew
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Aristarchus is a small to medium sized crater that is extremely bright and is probably one of the most recent large impact craters in the moon. It has long been suggested that there are occasional changes or activity in this region.
The video shown on youtube has rather poor resolution, focus and seeing and was taken using a very high degree of digital zoom so the pixels are quite large in the image. The slightly regularly flickering bright spot is the result of pixel integration as the bright area of the crater Aristarchus moves moves across the image because the camera has been fixed in position to get the best possible stability. the image is also slightly flickering generally due to the atmospheric seeing conditions which seem to be very poor although on a second viewing they may be due to the same effect of pixel integration on contrast edges. unfortunately there are no significantly straight lines on the picture which would clearly show what is going on by having spots moving along them.
What is happening is that when the crater is filling one pixel this pixel is very bright. when it is half in one and half in another it is much dimmer because if the inclusion if dimmer areas in the single pixel and therefore not so distinctly visible. When it is fully in the next pixel it is bright again. When looked at again in the context of the whole image it seems to move backwards and forwards a bit as well as flickering, this is another typical visual effect of this process.
The simplest example of the a similar visual process that I can think of to illustrate what I am talking about are the Moire fringes on sees when you view the word through two sets of railings while moving. you can se a mathematica demonstration here
http://demonstrations.wolfram.com/TimeAveragedMoireFringes/
Sorry no volcanic eruptions just a normal artefact of your way of creating the video.
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It's a combination of shimmer, (an atmospheric effect), and pixilation, (maybe some digital compression artifacts too (https://en.wikipedia.org/wiki/Compression_artifact#Video)) .
[ At 72x there may be some digital zoom (https://en.wikipedia.org/wiki/Digital_zoom) (in addition to optical zoom) which makes the image more pixilated than usual ].
There is free software called registax (http://www.astronomie.be/registax/index.html) which converts video blurred by shimmer into a single sharp still image by averaging-out the video frames ...
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Soul and RD
Apologies for poor quality video, Original footage prior to Youtube conversion is clearer and shows changing colours that looks like smoke / dust is distorting the light, almost as if the lights are rotating.
Could someone with better equipment take a closer look at the moon tonight, using the image from mine as a location guide?
You may be correct about pixels but it would be great to know for sure.
Best wishes and thanks for your thoughts
Andrew
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... looks like smoke / dust is distorting the light
Digital video compression artifacts can look like a cloud of mosquitos ...
Video compression artifacts include cumulative results of compression of the comprising still images, for instance ringing or other edge busyness in successive still images appear in sequence as a shimmering blur of dots around edges, called mosquito noise, as they resemble mosquitoes swarming around the object
https://en.wikipedia.org/wiki/Compression_artifact#Mosquito_noise
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You must note that your camera records colour images with a single sensor and this requires each pixel to be in triplicate with a set of red green and blue filters if this means that sub pixel bright patches passing through the image can create colour shifts as well as brightness shifts. I did not add this comment because the youtube video did not show strong colour shifts
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I agree with both of you that the chances of this being something other than a problem with the way digital cameras record light is remote. However, it appears that this particular area is under some debate as to whether it remains active or not.
Sci/Tech
Moon not quite dead
Clementine image of the Aristarchus region
By BBC News Online Science Editor Dr David Whitehouse
The Moon may not be the dead and unchanging world that many scientists believe. From time to time, parts of it may stir in a pale reminder of the volcanic and meteoric violence of its youth.
Some astronomers, who claim to have seen what they term as transient lunar phenomena (TLP) on its surface, have long suspected that there is some activity on the Moon.
For more than 450 years, there have been reports of TLP's - bright flashes to reddish or bluish glows hovering over certain craters and valleys. There are several explanations for them - weak volcanic activity, perhaps, or the escape of gasses trapped beneath the Moon's surface, or even impact by meteors.
More:
http://news.bbc.co.uk/1/hi/sci/tech/481455.stm
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... reddish or bluish glows hovering over certain craters and valleys. There are several explanations for them -
e.g. chromatic aberration ... https://en.wikipedia.org/wiki/File:Chromatic_aberration_%28comparison%29.jpg
There are precedents for optical phenomena being misinterpreted as structures/activity on heavenly bodies:
e.g Percival Lowell's Martian canals (https://en.wikipedia.org/wiki/Percival_Lowell#Astronomy_career), which don't exist on Mars and were probably the blood vessels in his eye.
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Thanks RD
closer footage from an independent viewer