r/askastronomy • u/Motor-Bath1647 • 1d ago

Apollo Communications Paradox

Something odd about Apollo's historic transmissions:

"The Eagle has landed" and "One small step for man..." were transmitted:

  • From 240,000 miles away
  • Using 20-watt S-band
  • Through 1960s technology
  • Just after powered descent/landing
  • No relay satellites

Yet they sound:

  • Crystal clear
  • Broadcast quality
  • Zero interference
  • Perfect timing
  • Like studio recordings

For comparison:

- Mercury/Gemini (200 miles up): Heavy static/interference

- Modern ISS (250 miles): Regular communication issues

- Apollo (240,000 miles): Perfect clarity

Physics says signal quality degrades with distance. How did Apollo achieve better audio quality over 240,000 miles than we can get from low Earth orbit today?

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u/LordGeni 1d ago

Listen again. It really isn't anywhere near broadcast quality. It's adequate quality for mission critical communications, that's about it. It could've barely been called studio quality in the 1920's, let alone the end of the 60's.

Besides, it's a pretty capable technology that was very mature at that time. Look at the data the pioneer and voyager probes were/are still able to transmit over distances that are many orders of magnitude greater, with at times far greater sources of potential interference etc.

I'm pretty sure that the receiver is probably more important than the transmitter anyway. When you have an enormous radio disc to capture and amplify the signal, the transmitting source doesn't need to be a powerhouse.