Talk:2428: Mars Landing Video

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When I saw "full speed landing" I thought it meant failed landing, as in a 2000-mph rover landing. --Char Latte49 (talk) 19:53, 22 February 2021 (UTC)

I thought that too. Elektrizikekswerk (talk) 07:55, 23 February 2021 (UTC)
Are you talking about lithobraking? -- Hkmaly (talk) 02:09, 24 February 2021 (UTC)
Yes, but without the airbags ;) Elektrizikekswerk (talk) 07:37, 24 February 2021 (UTC)

Why the specification that the video is full-speed? Did we already have slow motion video of a Mars landing? Bischoff (talk) 09:35, 23 February 2021 (UTC)

full-speed in the context of video usually means 24 to 30 frames per second(FPS) (or 60 fields if interlaced) and slow motion is anything 60fps or faster, but it is the ratio of recording speed to playback speed that matters. Record at 120fps and play back at 30 and you get smooth 1/4 speed slow motion; record at 24fps and play back at 6 and you get a jerky almost stroboscopic effect. The NASA press briefing included a “1/3 speed” video, which implies 75 to 90fps, but for all I could tell they might have simply slowed down the playback of the “full speed” feed. I suspect that prior landings had at best a handful of images that would constitute a playback frame rate of less than 1 per second, and thus would best be described as time lapse.108.162.219.56 12:13, 23 February 2021 (UTC)
I've not been keeping track of what was released when, but it was essentially "a series of stills" (i.e time-lapse, when compiled into a short video) for most(/all?) recent missions. Sometimes at the speed of capture (low-FPS playback), sometimes at a better speed of comprehension (sped up), sometimes possibly a mix (the comet impact/sampling video, I think had notes about it actually being five seconds of contact, but only usable pictures were edjted into the 'flickerbook' view).
The problem these days is probably more the bandwidth to send captured data back. Hardware and storage are probably capable, these days, as long as all vital science/navigation information can also be bit-shifted alongside the interest-raising videos more tuned to publicity. But once settled down, and while everything mission-critical is now being assessed back home it can probably trickle some HD video back (ready to re-use the memory space, shortly) to let them entertain the masses. ;) 162.158.155.204 13:07, 23 February 2021 (UTC)
Maybe some of this information about the "full-speed"ness of the video belongs in the main explanation body? --Markjreed (talk) 14:22, 23 February 2021 (UTC)

"The comic plays on the fact that if there is only one of something in a set, that one thing is the most/least in that set by lack of comparison." This is the math perspective. There are grammarians who insist that you shall not use superlatives* if there are less than three examples. When the math teacher calls the English teacher "My dearest wife" she slaps him and files for divorce on the grounds of trigamy.

  • OTOH both view accept that comparators must apply to exactly two examples.

162.158.78.108 17:32, 26 February 2021 (UTC)

A "sky-hook" is (according to the OED), "An imaginary device for or means of suspending something in the sky." (first citation 1888). (This is something I have heard of before). I thought that Randell might have meant that imaginary device, but then discovered that he was just referring to the Mars landing device - shame - sky-hook might have been better! Kulath (talk) 20:21, 27 February 2021 (UTC)

Not sure that would have been an improvement. Sky-hooks apply to every situation/no situation in particular (or perhaps best for a talk on the historic Fulton Surface-To-Air Recovery System), and makes little sense in intruding into a NASA presser. This was a "they used a sky-crane, I shall use a sky-crane!" situation. That's definitely apt. (Maybe he can bring up actual sky-hooks when NASA is unveiling some plan for a momentum-exchange tether to use for orbital lofting..?) 141.101.99.115 22:15, 27 February 2021 (UTC)