Moon landing Query

I used to doubt that man walked on the moon . Then I accepted the OS , but there is one point that eats away at my logic and it is ....Why was there little or no delay in transmition between the moon and earth and vice versa ?

Even today , Interviews carried out via satellite , experince a delay of circa 4 seconds . Yet this delay is not present with the apollo missions . !!!

reply to post by tpg65


Someone explained it to me in a way that actually made sense.....though I can't quite remember the argument so I'll have to wing it from memory. Basically we are only hearing one side of the audio.....recorded on earth. It takes something like 4 seconds to get to the Moon..(I can't remember the exact numbers...but I think I'm in the ballpark)..then it obviously takes 4 seconds for the reply to come back to Earth. Well if you are recording it on Earth, then you will hear Ground Control reply as soon as they hear the Lunar Lander's message rather than hearing a delay.....because you are hearing it as it broadcast to the Moon, rather than after it reaches the Moon...there still will be a delay on the replies coming from the Moon itself...but on Earth, we hear the replies from Ground Control without a delay because it was recorded on Earth. The astronauts still have to wait another 4 seconds before they hear it of course. This explains at least some of the lack of delay. Hopefully that all made sense.

Even though there is still plenty of things that bother me.....The biggest in my mind is how we had a VTOL craft that was sophisticated enough to come shooting out of the lunar sky at thousands of miles an hour...right itself...come to a stop, and then land...all without the aid of aerodynamics to guide it....instead using only rocket thrusters...and in an environment that was completely Alien with less gravity, yet the same amount of inertia....How we can do that when our modern VTOL craft (other than those that use air such as helicopters) can barely lift off....hover ......and turn around 360 degrees.....baffles me,,,,,

reply to post by bhornbuckle75


It's actually 1.3 seconds. So, the total lag-time in round-trip Earth-to-Moon communication is 2.6 seconds. And, as you say, this lag is only present in the Apollo response to Mission Control. MC responds without delay to Apollo, due to the recording of the transmissions being made on the MC end.
I listened to much of the Apollo communications listening for just this effect. The correct lag-time is present throughout their communication.

reply to post by tpg65


The earth-moon distance averages about 1.2 light-seconds, therefore propagation delay will be just a little longer than that. Since the signal from the moon was an analog, dedicated channel there should be little additional latency.

Distance to a geosynchronous communications satellite averages about .25 light-seconds, but since a signal must travel up to the satellite then back down to the receiver, the total propagation delay is twice that, or half a second. In practice, the best-case delay is actually about 700ms due to latency introduced by digitizing the signal and multiplexing it.

In short, you should only see about 500ms difference between Earth-Moon and Earth-Satellite-Earth communications.

reply to post by CLPrime


Yeah, It think you are right...I think I was mistaking it for how long it took for a round trip (which I remembered as being something like 3 or 4 seconds) ......But like I said..I was winging it from memory...thanks for the correction

Thank you guys

The video feed of the moon landing was filmed in a studio.
Not to say we didn't actually land on the moon, because we did. But the video wasn't real

reply to post by Denali


Quite possible of course. That's quite a specific stance on the subject..... Could you go into your reason's for believing this a bit. (just your main points...you don't have to go over every tiny piece of evidence that brought you to this conclusion, as I know this can be quite an involved subject)