Parachutes give little or no control over where and how the rocket lands, are unreliable (unfurling fabric behaves chaotically; modern spacecraft still don't have 100% reliability on their parachutes), and are surprisingly heavy.
Wings and landing gear are useless extra weight during launch, and excess weight on the booster has a super-linear reduction weight delivered to orbit. (the Tyranny of the Rocket Equation)
During the 1960s, NASA investigated using inflatable Rogallo Wings (basically hang gliders) to land the Gemini capsule. It worked fine, but was more complicated than parachutes, and re-use was not one of the goals of the Gemini or Apollo programs.
None of those give much margin for error on landing. Without any kind of propulsion, there's no option to come to a hover or do another go-around if the landing isn't going well. Space Shuttle pilots had to do extensive training in simulators for the landing because they only got one shot at it during the mission.
Propulsive landing doesn't require any hardware that isn't already on the launch vehicle, only a little excess propellant. (And it is a small amount; Super Heavy is like a soda can that's full of liquid at launch and only has a swig at the bottom during landing.) Propulsive landing gives Falcon 9 and Super Heavy the ability to overcome wind and other weather conditions to make pinpoint landings. Engine throttling gives Super Heavy the ability to hover, so it has a huge margin for error when coming in for a landing.
Super Heavy could have had legs, like Falcon 9, but it has such a huge payload capacity that they can simply choose to always launch with enough propellant to come back to the tower, and it saves a lot of flying weight and complexity by simply not having them. The arms on the tower can be massively overbuilt to ensure however much reliability SpaceX wants.
at two millihertz of bandwidth, you could transmit a 30-pixel line in only 7500 seconds, so you could transmit an entire 30×30 frame in 225 000 seconds, less than three days
but plausibly the millihertz notation was an error and megahertz was meant
Full blown color NTSC managed with 6mhz channels! Digital broadcasts have a terrible user experience: Instead of providing the same channel they always did, but to vastly more receivers in much more marginal conditions using advances in digital signal processing and encoding power and methodology, broadcasters were allowed to cut up their frequency into 6 "subchannels", so they crunch the streams to the shittiest quality they can (as low as 3mb/s, DVD is 10!) legally get away with, provide almost zero redundancy in the broadcast, so now TVs that were well in the broadcast area of analog signals are straining to get every last bit out of the digital stream so it can hope to recover a picture.
They did this because 6 channels that most people cannot actually receive over the air gives them more advertisement slots than the 1 previous channel. Good old enshittification.
Not only did it manage, it looked fantastic, at least at the source. Back in the 80s I had a chance work with high-end analog video gear at a broadcast production studio. You wouldn't believe the detail and color fidelity of a full 6 Mhz composite video signal coming straight out of a broadcast studio camera through a Grass Valley video switcher to a studio reference monitor. It had a lot of the subjective character audiophiles use to describe tube amplifiers like: depth, warmth, etc. After being recorded on a 2-inch broadcast quad tape machine (the size of a dishwasher!), the playback looked identical to my eyes.
Of course, by the time these pristine images lost several generations through editing and dubbing, were sent through RF distribution, up a transmitter, down an antenna and through 75 ohm coax house cable, they could look decidedly less amazing. :-)
In the 90s, analog component video looked even more impressive still and we could record and dub it digitally on D1 digital VTRs with no generational loss (and no compression!). Since so much of the analog standard definition TV historical footage we see today was recorded post-edit & dubbing and then captured on VHS or 3/4-inch U-Matic tape air checks, it doesn't reflect the remarkable quality we had back then. And worse, much of what we see today of analog video is also not properly de-interlaced during digital conversion and then is further degraded through over-compression for streaming or broadcast. The worst of all worlds...
To your point, the quality we had back then makes the peggish mess created by today's over-compression all the more egregious. I have a high-end 4K HDR10 home theater with top notch components all properly interfaced, calibrated and tested - and yet, outside of 4K Ultra HD discs, much of what I see on OTA broadcast, cable, satellite and streaming looks pretty awful.
> and yet, outside of 4K Ultra HD discs, much of what I see on OTA broadcast, cable, satellite and streaming looks pretty awful.
And that's why I keep my grandfathered Netflix 720p subscription. Shitty compression with low resolution vs shitty compression with higher resolution means the same amount of artifacts anyway.
Liftoff was published January 3, 2023
Reentry was published September 2024
https://www.harpercollins.com/products/liftoff-eric-berger?v...
https://benbellabooks.com/shop/reentry/
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