Flat earth: Water sticking to a rotating ball

Spinning rock

This video shows a spinning rock which rotates. It’s covered with a thin layer of water. Could it be the Holy Graal of flat earthers? Water sticking to a spinning ball?

Checkmate again, flat earthers.

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Flat Earth: CGI and NASA pictures

I bought an old astronomy book, printed in 1974, long before modern CGI.

In it, at page 81, there is a picture of earth from space (Apollo 16, on april 16,1972);

Apollo 16 earth from space

and it matches exactly with this picture on the web (except for color, since in the book, it’s B&W).

Apollo 16 picture

The book is “Fundamental Astronomy, Solar System and Beyond” by Franklyn W. Cole John Wiley & Son 1974 ISBN 0 471 16472 0

Fundamental Astronomy, Solar system and beyond


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Flat earth, curvature from space

In this flat earth video: TERRE PLATE !! LA PREUVE sous vos nez 👃 !!

We see a U2 plane in the edge of space, where we can see the earth. Flat earthers say there’s no curve. But compressing the image horizontally, the curve is there. Here’s a snapshot, intact.


Here is the same image, compressed horizontally.


Here’s another snapshot with the intact image and compressed, side by side.


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FE reflections on curved surfaces

For some reason, flat earthers say that reflection on a curved surface is impossible. Some attempted to prove this with a mirror inside a box and shooting a laser at it. However, his setup was incomprehensible as much as his explanation. I tried a little experiment to show that such reflections are possible on a curved surface. I don’t know if it disproves the flat earth claim.

Reflections on a curved surface

The video shows a reflection on a flat screen monitor and on a couple of curved screen monitors.

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Z80 Monsputer: Bus manager and probe


There are 2 new boards for the Z80 Monsputer; one is a bus manager (at top) and the other is a bus probe for a logic analyser.

The bus manager can be used for single stepping through the code by pulling down the Ready/!Wait line of the Z80 CPU. The management is done by an Atmel ATmega328pb clocked at 16 MHz. The other chip is a CPLD implementing a 48-bit SPI shift register to read the bus signals and controling the Ready/!Wait line.

The user interface is done with a serial port.

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Z80 Monsputer: CPU board cleanup

I posted some pictures of the Monsputer CPU board, which had numerous ugly patches. By substituting a smaller chip with more pins, I was able to put all the glue logic in the CPLD. Here is the top and bottom pictures. Much cleaner … well, for a manually routed PCB. Also, a Dallas DS1312 makes a better circuit for powering the CMOS 8K RAM.


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Earth’s orbit

Here is a common concept among flat earthers: the Earth circles the Sun. In order to keep up and pass it (circle it) Earth must speed up to pass, and then slow down once it’s passed (circled).

It’s partly true. That’s the acceleration component along one axis.

There is also another component of this acceleration along a perpendicular axis: once it’s passed the sun (in one side) it accelerates and slows down to get to the other side.

These 2 components combine into a circle, or a vector that’s oriented towards the center of the orbit. You can see clearly the principle here:



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