Newton's law of gravitation: Apollo 15 gravitation experiment
Apollo 15 commander David Scott dropping a 1.32-kg (2.91-pound) aluminum geological hammer and a 0.03-kg (0.07-pound) falcon feather on the surface of the Moon and proving that objects undergo the same acceleration in gravity, August 2, 1971.
NASA
-
Encyclopædia Britannica, Inc.Erik Gregersen, astronomy and space exploration editor, discusses space junk—material left floating in space after past space missions—and how the problem is getting worse every day.
-
Encyclopædia Britannica, Inc.This was a game-changer.
-
Encyclopædia Britannica, Inc.Understanding energy flow in ecosystems.
-
Contunico © ZDF Studios GmbH, MainzWatch a German air force pilot training to withstand the stresses of flight in a centrifuge that produces centrifugal force as great as 9g.
-
Encyclopædia Britannica, Inc.Learn what determines whether an object in water will float or sink.
-
© MinutePhysics (A Britannica Publishing Partner)Learn how the solar system, which formed from a roughly spherical cloud, became flat.
-
Contunico © ZDF Studios GmbH, MainzLearn how sea level is measured.
Transcript
ALLEN: Jim, we copied both solar wind and penetrometer drum in the ETB.
IRWIN: Not quite yet. I haven't put the solar wind in yet; but I will, shortly. I want to watch this.
SCOTT: Joe, I hope you have a good picture there. I've got . . .
ALLEN: Beautiful picture, Dave.
SCOTT: Well, in my left hand I have a--a feather; in my right hand, a hammer. And 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. And we thought that 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 happens to be appropriately a falcon 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?
ALLEN: How about that!
SCOTT: Which proves that Mr. Galileo was correct in his findings.
ALLEN: Superb.
IRWIN: Not quite yet. I haven't put the solar wind in yet; but I will, shortly. I want to watch this.
SCOTT: Joe, I hope you have a good picture there. I've got . . .
ALLEN: Beautiful picture, Dave.
SCOTT: Well, in my left hand I have a--a feather; in my right hand, a hammer. And 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. And we thought that 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 happens to be appropriately a falcon 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?
ALLEN: How about that!
SCOTT: Which proves that Mr. Galileo was correct in his findings.
ALLEN: Superb.