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Re: Planet X: ALTERNATIVE Garbage <= THOLEN! 1


David Tholen wrote:
> Nancy Lieder wrote:
>> You have NO comment on 2001 KX76 being called a REDISH OBJECT,
>> which is typical, in the press?  No comment whatsoever,
>
> Well, if you insist, I'll note that the V-R color published in
> IAU Circular 7657 on 2001 July 5 is 0.5 magnitudes with an
> uncertainty of 0.1 magnitudes; note that the V-R color of the
> Sun is 0.365, so this object is redder than the Sun by just
> 0.135 magnitudes, with an uncertainty of 0.1 magnitudes.  There
> are plenty of asteroids redder than that.  Much redder.  Nothing
> particularly unusual about this one.
>
> 2001 KX76 is not the "two red dots" (one bright and a fainter one
> to the left).  Rather, the object is the bright red dot and the bright

> cyan dot below it.  The coloration is an artifact of the method
> used to find the objects in the first place.  Two images are taken
> of the same piece of sky something like one hour apart.  One of
>  the images is loaded into the red plane of the computer display
> monitor.  The other image is loaded into the green and blue
> planes of the computer display monitor, but shifted, if necessary,
> to make the stars line up.  Once the stars are lined up, the red
> green and blue phosphors make the stars look white, but any
> object that has moved, such as an asteroid, won't have the red
> phosphors line up with the green and blue phosphors, so you
> wind up with one red dot and one cyan dot (cyan is the color
> you get when you mix the green and blue phosphors).
>
> So, what you're looking at isn't even a true color picture.
> It's a superposition of two black-and-white pictures loaded
> into the computer display memory in a way to make it easy for
> the human eye to pick out moving objects by visual inspection
> of the image.

Thanks for the clarification, Dave!  Bottom line, it is TYPICAL for
moving objects being recorded in this manner.

Magnus Nyborg wrote:
> By superimposing a red image on top of a cyan image (or vice
> versa) all stationary objects will appear as white dots, and all
> moving objects will appear as two colored dots, one dot
> representing the start and one dot representing the end.