Moonwalk :
India is about to land its rover on the lunar surface if everything else goes right. Right now it's orbiting the moon riding the satellite it was originally launched with.
Question : if the rover wants to travel the whole perimeter on the surface of the moon and return back to its starting point, how many kilometers does it have to travel?
We know that for going around the earth it's 40,000 km. As that's how the kilometer was defined initially.
For a rough calculation on moon, we have two data, the diameter of the moon in night sky, which is half a degree. And distance of the moon which is 400,000 km.
Calculating from these two give a number of 10,000 km. Which is almost what the actual figure is.
Ending with a moonwalk video going viral on social media. Even though it might look like it's in BD, it's actually from India.
https://www.facebook.com/9NewsMelbourne/videos/2498905736842116/
Old timer's nostalgia : in the 80s "moonwalk" actually meant MJ seemingly walking forward while actually moving backward.