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I've previously asked about how the recordings from the Apollo missions were originally recorded, and then transcribed; but I forgot about the video as well! It's well known that for some of the Apollo missions, when things didn't go awry, that video of the Lunar EVA's were broadcast live. However, when you think about it, it seems highly unlikely that NASA didn't have a back-up plan for the lunar footage.

For Apollo 16 and 17 there were problems with the Antennas which prevented the recording of the first steps on the moon from being transmitted for these missions. Does that footage exist on "tapes" brought back from the moon or something analogous? Or was the live stream being backed up at mission control and when the antenna went down, did all hope of getting that footage go with it? What was their backup plan?

My question is: Was the live stream back to Earth the only stream of data being recorded and the only life-line for the sending of visual images back to Earth? Was there any of the following:

  • A "tape-deck" on the LM (I don't know what format this would be in).
    • Physically recorded at the time of capture, to the Rover or LM.
    • Tapes brought back to Earth with the return of the capsule.
  • A recorder on the CM or back at mission control recording the live stream?
    • Would still suffer from black-outs of the live stream.
  • Something else?
  • Nothing else?

I don't know what data-compression looked like during these missions, but it wouldn't shock me if no local recordings were taken. The reels for the sound recordings alone were huge, I can't imagine what an AV reel looked like back then.

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The live broadcasts from the Moon were not recorded on the LEM/CM. Video tape recorders were too large at the time to make this practical. They usually came in the shape of an open-reel tape recorder with 2" wide tape.

This is the Ampex VR-660, a "portable" VTR that weighed 50 kg:

enter image description here

NASA used the VR-660 at ground stations to store slow-scan video.

The first video cassette recorder came on the market in 1971.

The first generation of U-matic VCRs were large devices, approximately 30 in (76 cm) wide, 24 in (61 cm) deep, and 12 in (30 cm) high

The astronauts did bring photo and film cameras, these images could not be transmitted live so they had to be brought back in the spacecraft.

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  • $\begingroup$ Space VCRs were still pretty huge in the year 2000. The black box behind Janet Voss's right elbow is a PHRR - basically a fancy VCR. spaceflight.nasa.gov/gallery/images/shuttle/sts-99/hires/… $\endgroup$ – Organic Marble Jul 23 at 16:49
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    $\begingroup$ I'm actually glad NASA didn't replace its 16mm film cameras with video recorders. Video quality was pretty bad in those days. $\endgroup$ – Hobbes Jul 23 at 17:59
  • $\begingroup$ Thanks for the history lesson on media formats too- super useful as to why! 50kg?! Might as well have a child stowaway! $\endgroup$ – Magic Octopus Urn Jul 23 at 18:37
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    $\begingroup$ Edit: The capstan tape speed is 3.7 inches per second, which provided a long record time of up to five hours on large reels. Oh my... that is... god awful. 300 minutes (5 hrs) for a 12-1/2 inch reel (5540 feet, 1 mile+) at 25 pounds. So not only was it 50kg for the recording equipment, but an additional 25kg per 5 hours.... brutally inefficient. $\endgroup$ – Magic Octopus Urn Jul 23 at 19:41
  • $\begingroup$ And the LEM after a moonwalk would be the worst possible environment for an open-reel tape recorder. Moon dust would quickly damage the tape and recording heads (the recorder uses helical scanning, the drum in the middle contains a set of heads that spin at high speed). $\endgroup$ – Hobbes Jul 24 at 6:05
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Hobbes' answer is correct, but here is some supplemental information.

The Erectable S-Band Antenna was a parabolic dish that was folded and stowed in the descent stage. Page 4-86 of the Apollo Program Summary Report describes the diameter as 10 feet and this NASA webpage says 3 meters. It was carried on Apollo 11-14. Although the LM could broadcast with its own S-Band antenna, it was believed the Erectable Antenna would be better for TV broadcasts. On Apollo 11, the smaller S-Band antenna mounted on the LM was deemed satisfactory and time was short, so they skipped erecting the 10-foot antenna. Apollo 13 didn't get to land or deploy the antenna. But the antenna was deployed on Apollo 12 and 14.

After egress, the astronauts set up this antenna on a tripod on the lunar surface. The TV camera and the 10-foot antenna were both connected to the Lunar Communications Relay Unit, which was kept in a drawer on the descent stage. The block diagrams of the LCRU do not show any recording mechanism.

During Apollo 15-17, the TV camera, LCRU, and a smaller replacement for the dish antenna were taken along on the lunar rover. TV broadcasts were sent directly to Earth. Carrying a video recorder would mean less weight available on the rover for tools and samples.


The command module actually had a TV monitor so the astronauts could see what their TV camera was recording. During some of the later flights, the CM TV camera could be attached to a boom which was in turn attached to the open hatch; I think that's why the monitor was needed. This monitor malfunctioned during Apollo 16, as documented in section 14.3.1 of its mission report.

Anyway, in an alternate reality, one could use a film camera to record what was on the CM TV monitor. That would preserve the TV images even if their broadcast failed. But that wasn't actually done. Nor would this have helped on the lunar surface, which had no TV monitor.

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    $\begingroup$ @JCRM: Thanks for your help. The answer has been updated and comments cleaned up. $\endgroup$ – DrSheldon Jul 24 at 0:28
  • $\begingroup$ I'm accepting Hobbes' answer, but wanted to thank you for the addition as well, all of that was new information to me. $\endgroup$ – Magic Octopus Urn Jul 24 at 15:18

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