Size of the Earth as seen from the Moon

The Size of the Earth as seen from the Moon

The size of the Earth in Lunar photographs seems very small. To find out the actual size of the Earth as seen from the moon some calculations are needed.

Firstly there is a formula: a=2 arctan (d/2D)

a is the angular diameter of the moon (~1.9)

d is the actual diameter of the Moon (~3500K)

D is the distance from the Moon to the Earth (~400,000K)

From this we get 3.75. So the Earth as seen from the Moon WILL look 3.75 times larger than the Moon appears from Earth.

There are NO Apollo photographs that show this. All the photographs of the Earth from the Moon show the Earth at the same size the Moon looks from Earth. This is part of the conspiracy. By showing the Earth at the familiar size of the Moon in the Earth's sky, people comfortably believed that the astronauts must be on the Moon's surface.

Image: NASA 1969

The image above shows the Earth as a crescent. This is correct, however, the size is too small.

Image: NASA

Image above shows the Earth at waxing gibbous. Again the Earth is too small. All pictures should show the Earth 3.75 times larger than this when seen from the Moon.

The flag and moon above is so unbelievable.

New Image

Rescently, NASA released the image below. It shows the Earth at its correct size. Why? Did our planet grow in the last 50 years?

NASA's Lunar Reconnaissance Orbiter (LRO) recently captured a unique view of Earth from the spacecraft's vantage point in orbit around the moon [NASA].

And below is a photograph taken by a satellite from ~1.6M kilometers out.

Image: NASA

Original Images Credit: NASA.

So the Earth as seen from the Moon WILL look 3.75 times larger than the Moon appears from Earth.

[Cudnik]Unlike the moon, which rises and sets regularly as seen from the Earth, the Earth is only visible from one lunar hemisphere, and for that hemisphere the Earth hangs
motionless in the black Lunar sky, slowly going through its phases while it sits there. The full Earth is some four times wider and eighty times brighter than the full moon.
During a full Earth period, if you could stand on the Moon‘s surface and block out the Earth with your hand, the sky would appear very dark and very full of stars. Since the
moon has no atmosphere, the light scattered from the full Earth is nonexistent, unlike the situation on the Earth‘s surface with the full moon[Cudnik 2012].

References

The Art and Science of Visual Astronomical Observations, 1E
© 2012 Brian Cudnik http://www.poyntsource.com/New/Cudnik_The_Art_and_Science_of_Visual_Astronomy.pdf

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