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Moon landing dialogue

Duke:  You are go you are go to continue powered descent. You are go to continue powered descent.

Aldrin:  Roger . We got the earth right out our front window.

[Altitude 33,500 feet.]

Armstrong:  Program alarm . It's a 12 02 . Give us the reading on the 12 02 program alarm.

[The 12 02 alarm, called an executive overflow, signaled that the Eagle's computer was overloaded. Mission Control concluded that the overload would not jeopardize the landing.]

Duke:  Roger. We got you. We're go on that alarm . Throttle down.

Ward:  Altitude now 21,000 feet. Still looking very good. Velocity down now to 1,200 feet per second . Seven minutes 30 seconds into the burn. Altitude 13,500, velocity now reading 760 feet per second. Descent rate 129 feet per second.

Duke:  Eagle, you're looking great, coming up 9 minutes.

Ward:  Altitude 4,200.

Duke:  Eagle. Houston. You're go for landing. Over.

Aldrin:  Roger, understand. Go for landing. Three thousand feet. Program alarm! 12 01.

Armstrong:  12 01.

Duke:  Roger. 12 01 alarm. [Pause.] We're go. Hang tight. We're go.

[Because the program alarms and the possibility of aborting the mission were the greatest concerns, Armstrong and Aldrin had up to this point been unable to evaluate landing sites. In a technical debriefing after the mission, Armstrong noted, "It wasn't until we got below 2,000 feet that we were actually able to look out and view the landing area." When they did, they saw that the Eagle's computerized guidance system was taking the craft toward a football-field-size crater surrounded by car-size boulders.]

Armstrong:  Pretty rocky area.

Aldrin:  600 feet.

[Two minutes of fuel left for the landing.]

Armstrong:  I'm going to

[Armstrong switched the guidance control out of automatic and began to direct the landing manually, positioning the Eagle at approximately zero pitch to slow its descent as he maneuvered past the crater.]

Armstrong:  I got a good spot.

Aldrin:  You're looking good . Five percent [fuel remaining]. Quantity light.

[Only 60 seconds' worth of fuel left for the landing.]

Duke:  Sixty seconds.

Aldrin:  40 feet, down 2 _. Picking up some dust.

[Armstrong would later report, "This blowing dust became increasingly thicker. It was very much like landing in a fast-moving ground fog."]

Aldrin:  Contact light.

[Three 10-foot-long probes attached to the Eagle's footpads touched the moon's surface.]

Armstrong:  Shut down.

Aldrin:  Okay. Engine stop.

Armstrong:   Engine arm is off. [Pause.] Houston, Tranquility Base here. The Eagle has landed.

The time was 4:18 EDT on July 20, 1969.

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