Artemis 2 will be doing its moon flyby today. Including the dark side of the Moon 👀
(media.greatawakening.win)
🍿 POPCORN 🍿
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Every earth pic from nasa shows us as a perfect sphere. Yet, when planes fly around the world many head north as it is shorter than around the equator. My understanding is we are a spherical globe misshapen.
We're a bit pear shaped.
The shape is called an "oblate sphere". Because the planet is spinning, quite fast I might add, the planet bulges at the equator a bit. The deviation is such, that to calculate your position on the planet using GPS signals, you need to account for this bulging, i.e. the diameter of the planet is not a constant, it depends on the direction, so the north-south diameter is smaller than the east-west diameter. The difference is 0.338%; not visible with the naked eye. The standard globe model used in GPS-positioning "WGS84" uses a 0.336% difference.
The reason planes fly north often is two-fold; the northern hemisphere is where most developed countries are located. It is also the hemisphere where most landmass is located. Take a globe (or use Google Earth) and draw the shortest line on the sphere connecting, say, New York and Moscow. The shortest route along the sphere is across Maine and the lower tip of Greenland, Iceland, Scandinavia, etc. It is fairly easy to see why this is the case.
Another example; Fly from Tokio to Boston. You will pass Alaska on the left!
Get a globe. It is fun!
Oh and before anyone asks; When flying from Johannesburg to Perth, one would pass over the antarctic as well, however, in practice, sometimes due to rules concerning diversion / ETOP, other routes, closer to airports may be chosen.