Monday, 31 December 2012

Moony Business

The Moon's polar circumference is 27.3% the size of the Earth's polar circumference.

The Moon orbits the earth every 27.3 Earth days and turns 10920.8 km at the equator every 27.3 days.  This equates to a speed of 400 km/h.  The Earth turns at 100 times the rate and travels 40,000 km per rotation.  Conversely the Sun is 400 times larger than the Moon and 400 times further away from Earth, which is why we get to see such great eclipses.

Earth turns 366 times each orbit of the sun, and is 366% the measurement of the moon at the polar circumference.  The moon orbits earth 366 times every 10,000 days.

There are 109.2 Earth diameters across the Sun's diameter.
There are 109.2 Sun diameters between the Earth and the Sun when it is at the furthest reach of it's orbit around the sun.
There are 109.2 x 100 km across the circumference of the Moon.

Please feel free to check these sums and come to your own conclusions :).

Friday, 28 December 2012

So you're telling me...


Diameter of Earth (km)  /  Diameter of Moon (km)  =  3.6668
12472  /  3475  =  3.6668

Strangely enough, the earth rotates 366 times in a single orbit of the sun.  And if you divide that recurring 400 by 3.66, you get that recurring 109.28.

More on 366 another time.  When I figure it all out....

400 and things


Wikipedia lists the moon's rotational speed at the equator as 4.627 m/s.  This works out as 16.6572 km/h.  Which means that in one earth day of 24 hours, it covers 399.728 km.  Which is about as close to that recurring "400" mentioned in the previous posts as can be.

Wikipedia also lists the earth's rotational speed at the equator as 1674.4 km/h.  That's pretty close to 100 times the moon's speed.

1674.4 km/h  /  16.6572 km/h =  100.521095

Therefore, in 24 hours the earth rotates 40185.6 km.

The moon covers 400 km  of ground in a day.
The earth covers near enough 40,000 km in a day.

Diameters and Things

Following on from the previous post, the moon has an equatorial circumference of according to Nasa, and 10921 if you get your figures from Wikipedia.

The Sun's Diameter is roughly 109 times the Earth's Diameter.  In fact, most peculiarly, it almost perfectly mirrors the figure in kilometres for the Moon.

Using NASA's data:

Sun's Diameter - 1,391,016km
Earth's Diameter - 12,742km
Moon's Diameter - 3,475km

Sun's Diameter divided by the Earth is 1,391,016 / 12,742 = 109.1678

And interestingly, the Diameter of the Sun divided by the Diameter of the Moon works out at 400.2923

So the Moon is 400 times smaller than the sun.

Luckily for us, it's also 400 times closer to us than the sun, so in the sky from Earth, they look exactly the same size.  Which is why we get eclipses.

There's no logical reason for this other than coincidence... but the coincidences just keep piling up...

Earth Moon and Sun Number Play

Circumference of the Moon - 10,917.0km (according to NASA)
Circumference of the Earth - 40,030.2km (according to NASA)

Circumference of the Sun - 4,370,005.6km (according to NASA)

(Earth's circumference x Moon's circumference)/100 = 4,370,096.934km

Now call me mad, but why on earth would the circumference of our planet multiplied by the circumference of our moon match the circumference of the sun so very closely?  Just a tad weird isn't it?
Maybe it's just a small coincidence?