BRAINDUMP
Amazing answers to your curious questions
Are Buzz Aldrin’s footprints still on the Moon? If so, why?
Bryn Biggs
We consider the Moon to have no atmosphere. There may be very small traces of some elements, but not enough to constitute an atmosphere. If there’s no atmosphere there can be no wind, as there will be no air to move around. With no wind there’s nothing to blow the footprints away, so yes, Buzz Aldrin’s footprints will still be there on the Moon, as well as any other footprints left by the 11 other astronauts who have been there.
WHY DO WE HAVE A KNEECAP, BUT NOT AN ‘ELBOWCAP’?
Cameron James
The kneecap is a sesamoid bone, which means that unlike most bones in the body it grows within the tendons that attach muscles to certain joints. Sesamoid bones form where a tendon passes over a joint, and their purpose is to protect the tendon and to increase its mechanical effect. Human knees are placed under a great amount of stress due to walking upright, and the kneecap is there to help maintain the knee’s movement and ability to flex in the correct manner. The elbow doesn’t suffer these stresses, as most humans don’t walk on our hands. Also, it would seem reasonable th at since our knees face forwards – the same direction that we crawl and walk – and our elbows face backwards, the kneecap evolved to protect the knee, whereas the elbow didn’t require such protection.
Did you know?
The kneecap is called the patella
CAN YOU HAVE TOO MUCH SLEEP?