If you perform a search for "flat earth" on youtube one of the top videos that comes up is a piece from National Geographic, which claims to have tested the curvature of the earth and found it to be round. Specifically, they brought in the Independent Investigations Group who were promoted as a group of science professionals to "test" the matter. They determined that the earth was curved and this was heavily promoted and featured by National Geographic in the video.
This is the National Geographic video:
Specifically, they lied about how many lines were seen when the boat and the board went into the distance:
At 7:54 the CFI Investigations Group says:
"We've lost about one and a half stripes; so this can only
happen because of the curvature of the earth"In the video preview on the YouTube search page there is also a teaser for the video featuing the Independent Investigation Group stating that this can only happen because of the curvature of the earth.
However, it is clearly not the case that one and a half stipes were missing. If you look at the striped board from other views before it went into the distance the red line was always at the bottom.
Close up; boat leaves and begins going into the distance:
In the distance:
There are no other shots of the boat in the distance. From this they concluded that one and a half stripes went missing. There is a little compression there, and it is possible that a very small portion of the bottom red line nearest the water might be missing for whatever reason, but it is clearly not the case that one and a half stripes went missing.
It is also apparent that the horizon is still behind the boat and the and the striped board, still intersecting it. If the boat and board were sinking into the horizon, then the bottom edge of the board is the waterline horizon and that is where the water would end. There should not be additional water seen behind the boat and the board cutting through behind it. If the bottom of the board and boat was the horizon then the surface of the water should curve away at that point.
If the boat is curving behind the horizon, you should not see a water horizon further in the distance. There is a diagram animated scene in the National Geographic video showing the boat receding from the observer, showing the surface of the Earth curving away into the red beneath the line of sight:
Embarassing.
It is possible that all of this is a simple mistake. But considering all of the National Geographic production effort put into this, the hiring and promotion of an independent "science" group, and the fact that this was played on television as an educational video; the inability to count the lines on the target, or look at their own diagrams and see that the water horizon is still behind the boat, can be interpreted as a lie via negligence. If it is a matter of severe negligence then it is still a lie because they claimed to the public that they at least performed basic due diligence on the matter and did not. The video eggregously promotes this as the science truth.
Especially if this is pointed out to them and they still do not remove the video; if YouTube and National Geographic keeps the video up and promoted then it is a heinous lie to the public. I would go as far as to advocate that tfes makes this one of its next front page posts, demanding an apology and retraction of the video content from National Geographic. If they do not remove it then it is clear evidence of a lie to the public by a high profile science and education organization.