水曜日, 12月 13, 2017

The Hammer and the Feather 1971

https://i.imgur.com/txweovp.gif
1971年、重力が地球の1/6の月面でハンマーと羽毛を同時に落下させる有名な実験。
動画音声ではガリレオについての解説がある。

I was watching Apollo 15 Astronauts Dave Scott and Jim Irwin busily loading the lunar module with exposed film and dusty moonrocks. As if cued by an invisible director, Dave turned and moved toward the television camera.

 "Well, in my left hand I have a feather; in my right hand a hammer. I guess one of the reasons we got here today was because of the gentleman named Galileo. A long time ago, he made a rather significant discovery about falling objects in gravity fields; and we thought - where would be a better place to confirm his findings than on the Moon? And, so, we thought we'd try it here for you. The feather is, appropriately, from an Air Force Academy falcon. I'll drop the hammer and the feather and, hopefully, they'll hit the ground at the same time."

Well, Dave let them go and, since there is no atmosphere on the Moon, they fell side by side. They did fall more slowly than on Earth because the gravity is one-sixth that of Earth's.

Dave continued, "How about that. This proves that Mr. Galileo was correct in his findings."




 At the end of the final moonwalk of the Apollo 15 mission in July 1971, Commander David Scott stood in front of the remote- controlled television camera to perform a live demonstration for viewers back on Earth. ... 

“In my left hand, I have a feather,” 
 “in my right hand, a hammer. I guess one of the reasons we got here today was because of a gentleman named Galileo a long time ago, who made a rather significant discovery about falling objects in gravity fields. ……The feather happens to be, appropriately, a falcon’s feather, for our Falcon, and I’ll drop the two of them here and hopefully they’ll hit the ground at the same time.”
“How about that?” 
 “Mr Galileo was correct in his findings!”


Audio: [Scott] "And I'll drop the two of them here and hopefully they'll hit the ground at the same time" [He drops them] "How about that?" "Looks like mister Galileo was correct in his findings."

The Hammer and the Feather - YouTube

https://youtube.com/watch?v=4mTsrRZEMwA




Apollo 15 Hammer-Feather Drop - the NSSDCA! - NASA

nssdc.gsfc.nasa.gov/.../lunar/apollo_15_feather_drop.ht...

At the end of the last Apollo 15 moon walk, Commander David Scott (pictured above) performed a live demonstration for the television cameras. He held out a geologic hammer and a feather and dropped them at the same time. Because they were essentially in a vacuum, there was no air resistance and the feather fell at the same rate as the hammer, as Galileo had concluded hundreds of years before - all objects released together fall at the same rate regardless of ...

APOD: 2011 November 1 - Hammer Versus Feather on the Moon

apod.nasa.gov/apod/ap111101.html

A good place free of air resistance to test this equivalence principle is Earth's Moon, and so in 1971, Apollo 15 astronaut David Scott dropped both a hammer and a feather together toward the surface of the Moon. Sure enough, just as scientists including Galileo and Einstein would have predicted, they reached the lunar surface at the same time. The demonstrated equivalence principle states that the acceleration an object feels due to gravity does not depend on its ...


David Scott ,Galileo

http://www.dailymail.co.uk/sciencetech/article-2819205/Testing-gravity-world-s-BIGGEST-vacuum-chamber-Watch-Brian-Cox-prove-bowling-ball-feathers-fall-together.html

https://books.google.co.jp/books?isbn...
Below Astronomer with astrolabe. At the end of the final moonwalk of the Apollo 15 mission in July 1971, Commander David Scott stood in front of the remote- controlled television camera to perform a live demonstration for viewers back on Earth. ... hand and a feather in the other. He released them at the same time, and, being in a vacuum with no air resistance, the feather and the hammer struck the lunar soil at exactly the same speed. "How about that," said Scott, "Galileo was correct.

One of the reasons we got here today was becouse of a gentleman named Galileo.
 "How about that," said Scott, "Galileo was correct.



http://www.americaspace.com/2012/07/29/mr-galileo-was-correct-the-legacy-of-apollo-15/

Back at the lander, with the minutes of the final Moonwalk rapidly winding down, Scott had one last opportunity to give a scientific demonstration to an audience of millions back home. It came from a suggestion by Joe Allen, who was inspired by the experimental work of Galileo Galilei. More than three centuries earlier, Galileo had stood atop the Leaning Tower of Pisa and dropped two weights of different sizes, proving that gravity acted equally on them, regardless of mass. Now, in front of his own Leaning Tower – the slightly-tilted Falcon – Scott performed his own version of the experiment.

“In my left hand, I have a feather,” he told his audience, “in my right hand, a hammer. I guess one of the reasons we got here today was because of a gentleman named Galileo a long time ago, who made a rather significant discovery about falling objects in gravity fields. The feather happens to be, appropriately, a falcon’s feather, for our Falcon, and I’ll drop the two of them here and hopefully they’ll hit the ground at the same time.”

They did…and applause echoed throughout Mission Control.

Standing in front of the lunar module Falcon, Dave Scott prepares to drop a feather and hammer in demonstration of Galileo Galilei’s famous experiment of falling objects in gravitational fields. Photo Credit: NASA

“How about that?” Scott concluded triumphantly. “Mr Galileo was correct in his findings!” He originally planned to try it first, to check that it would work, but was worried that it might get stuck to his glove. He decided to ‘wing it’ and, thankfully, it worked. In his autobiography, Irwin would relate that Scott had actually carried two feathers on Apollo 15, one from the falcon mascot at the Air Force Academy. Unfortunately – and much to Scott’s irritation – Irwin accidentally stepped on it! They searched for the feather, but could only find his big bootprints. “I’m wondering,” wrote Irwin, “if hundreds of years from now somebody will find a falcon’s feather under a layer of dust on the surface of the Moon and speculate on what strange creature blew it there.”