I guess doing just a bit of research would be too hard.
As the descent began, Armstrong and Aldrin found that they were passing landmarks on the surface 4 seconds early and reported that they were "long" (they would land miles west of their target point).
Five minutes into the descent burn, and 1,800 m above the surface, the LM navigation and guidance computer distracted the crew with the first of several unexpected "1202" and "1201" program alarms. Inside Mission Control, computer engineer Jack Garman told guidance officer Steve Bales it was safe to continue the descent and this was relayed to the crew. The program alarms meant the guidance computer could not complete all of its tasks in real time and had to postpone some of them.
When Armstrong again looked outside, he saw that the computer's landing target was in a boulder-strewn area just north and east of a 300-metre diameter crater. Armstrong took control and, with Aldrin calling out altitude and velocity data, landed at 20:17 UTC on July 20 with about 25 seconds of fuel left.
Because there was a pretty big boulder at the original location, and if they had landed there the lunar module would have tipped over and landed on its side instead of the landing pads.
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I guess doing just a bit of research would be too hard.
As the descent began, Armstrong and Aldrin found that they were passing landmarks on the surface 4 seconds early and reported that they were "long" (they would land miles west of their target point).
Five minutes into the descent burn, and 1,800 m above the surface, the LM navigation and guidance computer distracted the crew with the first of several unexpected "1202" and "1201" program alarms. Inside Mission Control, computer engineer Jack Garman told guidance officer Steve Bales it was safe to continue the descent and this was relayed to the crew. The program alarms meant the guidance computer could not complete all of its tasks in real time and had to postpone some of them.
When Armstrong again looked outside, he saw that the computer's landing target was in a boulder-strewn area just north and east of a 300-metre diameter crater. Armstrong took control and, with Aldrin calling out altitude and velocity data, landed at 20:17 UTC on July 20 with about 25 seconds of fuel left.
Because there was a pretty big boulder at the original location, and if they had landed there the lunar module would have tipped over and landed on its side instead of the landing pads.
http://www.lpi.usra.edu/lunar/missions/apollo/apol...
http://next.nasa.gov/alsj/a11/a11.landing.html
Somewhere in that transcript and all that technical jargon is the answer to your question.
Radar data overwhelmed the LEM computer ... Armstrong had to take manual control to land.