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Comment by ChuckMcM | Hacker News Reader

Well that answers the question of why they were following the first stage and why it seemed like it still had its legs (you can see one sticking up in the tweeted photo).

Since I have to guess, I'm guessing it stayed closed up most of the way down, avoiding perhaps even grid fin erosion during high re-entry speeds. It is fun to see a company that has rockets it can expend for experiments like this because it is so far ahead of its nearest launch competitor in terms of costs.

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They're not expanding it for experiments. It's just an old model that costs too much to refurbish, and they've got a new one coming up which will be a lot cheaper and easier to refurbish than the current (which is one model ahead of the just-launched rocket).

And once you're throwing it out, might as well do some experiments.

> And once you're throwing it out, might as well do some experiments.

I understand what you're saying here, but the extent to which the aerospace industry just does not work this way is staggering.

This is a fairly unique quality of SpaceX.

.. not to mention the fact that "once you're throwing it out, might as well do some experiments" is not how the incumbent space companies was operating, before SpaceX came along. For them, it was more like "we've got a near-infinite supply of cash from the government, lets just submit another PO for the next round of experiments" ..

Gwynne Shotwell (CEO of SpaceX) stated near the end of this video[1] that the reason they had such good video coverage is that they usually follow the second stage, but in this case it was a classified mission and were forbidden to do so. The cameras followed the first stage return instead.

[1]https://www.youtube.com/watch?v=kjTHJzWPTnU

Those are great videos, in this case I was talking about the launch of GovSat-1 (non classified) which was a launch to GEO so a high delta-v launch. SpaceX has generally defined these as 'unrecoverable' for at least two reasons; the first stage is going too fast making reentry quite 'hot', and they have used all the fuel to boost mass rather than save some for landing.

So when they stood up the rocket and it had landing feet attached I was curious (why waste the weight of those feet if you aren't going to land it?). My guesses were that either it was too much work to remove them (it was a pre-flown booster) or some other experiment. It turns out they were experimenting with a different return profile that could allow them to land this type of mission's booster.

Your "following the first stage" made me think of the Zuma launch footage and I forgot this was about GovSat-1. Nice there are so many going on that it is easy to mix them up.

On further research I think it was the NROL-76 launch with a classified payload in spring 2017 that she was talking about.

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