Wednesday, June 8, 2022

A step even farther out

Longtime readers will no doubt be shocked to find out that I am a nerd, and have been for a long time.  Back in the 1970s I subscribed to Galaxy science fiction magazine in no small measure because of Jerry Pournelle's monthly column "A Step Farther Out" about space and space technology.

I've just run across a blog that is basically this for the modern age: Casey Handmer is a former JPL techie who seems to be in one of the many space exploration companies that are popping up everywhere these days*.  I think I ran across his blog via a link at The Silicon Graybeard, but Handmer doesn't focus on "what's the space news from this week" - rather, it's in-depth discussion of fascinating topics that I either didn't know, or topics that I thought I did know but actually knew wrong.  Here is a smattering of some of the most interesting ones:

OMG space is full of radiation, and why I’m not worried
Domes are over-rated
Modular space stations don’t save time or money
The Moon’s water is less exciting than you might think
There are no known commodity resources in space that could be sold on Earth


And the most important of his posts (IMHO) is this one: .  Here's the key bit:
Historically, mission/system design has been grievously afflicted by absurdly harsh mass constraints, since launch costs to LEO are as high as $10,000/kg and single launches cost hundreds of millions. This in turn affects schedule, cost structure, volume, material choices, labor, power, thermal, guidance/navigation/control, and every other aspect of the mission. Entire design languages and heuristics are reinforced, at the generational level, in service of avoiding negative consequences of excess mass. As a result, spacecraft built before Starship are a bit like steel weapons made before the industrial revolution. Enormously expensive as a result of embodying a lot of meticulous labor, but ultimately severely limited compared to post-industrial possibilities.

Starship obliterates the mass constraint and every last vestige of cultural baggage that constraint has gouged into the minds of spacecraft designers. There are still constraints, as always, but their design consequences are, at present, completely unexplored. We need a team of economists to rederive the relative elasticities of various design choices and boil them down to a new set of design heuristics for space system production oriented towards maximizing volume of production. Or, more generally, maximizing some robust utility function assuming saturation of Starship launch capacity. A dollar spent on mass optimization no longer buys a dollar saved on launch cost. It buys nothing. It is time to raise the scope of our ambition and think much bigger.
He then goes on to think bigger.  There's all sorts of things wrong in this world, but what's happening in space is not on that list.  We are witnessing the birth of The industry of the 21st Century, just like aviation was the industry of the 20th.

Pournelle wrote a column when the Space Shuttle Enterprise first flew, comparing it to the DC-3 "Gooney Bird".  I think that Starship is the actual space DC-3.  It will make space travel routine, in ways that we can't imagine any better than someone looking at the first DC-3 in 1935 could.  They would never have figured on Freddy Laker's People's Express; we can't imagine what a Moon Shuttle will be.

* Now this is the 21st Century I was promised. 

5 comments:

Beans said...

Comparing cargo capacities, going aviation isn't the way to do it.

Unless you're comparing pre-WWI aircraft to said DC3.

It's more like comparing Liberty ships with a day-sailor or john-boat.

That is the true difference. One can carry minimal cargo and people, that would be Legacy Aerospace products. The other can carry people and cargo and whatever, and do it continuously with little futzing with (once all the kinks are out.)

Educated Savage said...

Your footnote about the 21st century is my thought exactly. There might be a lot going wrong, but private space flight isn't part of it. I had the same response the first time I used a die casting mold that had 3D printed cooling channels in it.

Joe Texan said...

I still have my copy of Pournelle's book, "A Step Farther Out." It must be a compilation of those columns he wrote. I used to re-read and be saddened by how much we haven't accomplished. Elon Musk has changed my mindset, so when I read it now, I'm excited about the prospects again.

Unknown said...

I'm grateful to SiG for linking to Mr. Handmer's blog. That is a rabbit hole that I dare not go down too far at any given point if I want to get any work done.
My one "criticism" is that he is making me reassess some of my postulations in my hard sf alternate history series about a more technology based response to the events of 9-11.(Though not the politics, which is intended to be more of an Allen Drury Advise and Consent novel, written by an engineering designer and historian instead of Drury's journalism background).

jabrwok said...

The sooner I can emigrate to a Bishop Ring space habitat, the better.