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Comment by dnautics | Hacker News Reader

I definitely get this feeling though: "congratulations you skilled superhero bastards, now never do it like this again".

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There were DARPA-funded projects back in 2004 to try to avoid doing it like this, while it was being built. They were funding investigations into assembling the satellite on orbit, e.g. send up the segments one at a time and dock them together on orbit. Those projects were cancelled in W. Bush's second term after he pushed for manned missions again. To this day, I still think in space assembly would have been cheaper and possibly lower risk.

JWST and most scientific instruments are extreme one offs that take a long time to build and don’t have backup parts. So if anything trying to dock multiple parts in orbit would have likely increased costs and risks.

There is a very small risk of a launchpad failure, but sending up multiple launches only increases those risks. Further, building a second one would have been much cheaper though still very expensive.

The basic technology of robotic space construction, though, could have far reaching benefits in its own right. So while it may not be strictly better for this one mission, it might still pay put dividends in the long run.

I think everyone felt that about the skycranes on Mars too (like... both times).

Were there delays caused by it, though?

I have no idea what the causes were specifically, but Curiosity was over two years late in launching (planned Sept 2009, actual Nov 2011), per:

https://en.wikipedia.org/wiki/Timeline_of_Mars_Science_Labor...

When it comes to Mars, though, even if you’re only a month late it will normally result in a 26-month delay due to how often (or rarely) launch windows open for Earth–Mars Hohmann transfers, and this is exactly what happened with Curiosity.

Here's more on why: https://www.thespacereview.com/article/1319/1

TLDR: It was not the EDL [edited to add: entry descent and landing] system, it was the fabrication and integration (putting together) of certain actuators that are used in low temperatures at Mars. People at a contractor, and at JPL, were putting in double shifts and they came within a very close margin of getting it together.

Additionally, there were flight software/avionics issues.

But if you're set to miss the launch window by even a week, you have to wait for the next one 26 months later.

I was actually surprised (happily) that they succeeded. It just seemed to be too many precise complicated manoeuvres that weren’t allowed to fail.

Is it that? Or is it maybe a sign that the current era is a little hyper-critical and in that hyper-criticality lost touch with what's actually possible and acceptable risks? This was no small engineering feat. It's also a good demonstration of the world of the possible.

Well the delays were a real thing, I don't think it is uncoupled from the engineering methodology

Seconded.

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