[bangelo]

So I'm a fan of spacex in the sense that they're taking an atraditional approach to space exploration and colonization. However, our current ride to space has been operating reliably since 1978, we've been building and sending large space stations up since the early 70s. Spacex only very recently got their closed cycle engine working, the pinnacle of rocket efficiency, catching up to, again, early 1970s Russian technology. Taking the human out of the loop by automating Dragon is great, but remember, we sent three humans to the moon in, you guessed it, the 70s, with less computing power than my toaster oven. Hats off to the team for what they've done thus far. it's a momentous achievement for the private sector, but they have a ways to go before any kind of groundbreaking achievements. Fantastic marketing though |)

[InclinedPlane]

We sent people to the Moon decades ago for roughly a billion dollars per astronaut (adjusted for inflation). That's the incremental cost, not even including development costs. It's no wonder we never went back to the Moon, it wasn't sustainable. Even crewed spaceflight in general has been questionably sustainable. The ISS cost over $100 billion to assemble.

SpaceX has been driving not just innovation but a much faster pace of innovation. Landing rockets, reusing rocket stages of orbital launchers, developing crewed spacecraft on a budget roughly an order of magnitude cheaper than the way government procurement works. Etc, etc, etc. Ten years ago there had been zero Falcon 9 launches. Today the Falcon 9 makes up the majority of commercial orbital launch traffic, has flown over 60 times, has been landed over 20 times, and has been reused nearly 20 times. And the pace is accelerating. They're working on new engines, new vehicles, new ideas. All of which has dramatically shaken up spaceflight and opened up the possibility of a new space age where access to space is a lot cheaper and more routine than it has been.

[agildehaus]

I like how you list all these things and entirely leave out the landing an orbital class rocket, which no private company nor governmental agency has ever done.

They're also pretty much doing it all themselves for a fraction of the price due to vertical integration, which is also unique.

Raptor is a full-flow staged combustion engine. Others have been made, yes, but none have flown. Right now Raptor is the only methalox variety of such an engine to ever reach a test stand.

[avmich]

Agree. As it's usually the case, they achieve a lot by standing on the shoulders of giants, but they achieve nevertheless. Space Shuttle was splashing down solid boosters since early 80's - but SpaceX lands softly liquid first stages, which require much less pampering to prepare for the next flight. Capsules are built and flown since early 60's - but SpaceX first tests a capsule for more than 3 people. And reuses a cargo spacecraft after splashdowns. And has lots of launches per year of a rather heavy rocket (previously some years have seen similar activities with Soyuz rockets, but then a government was fully behind it). And all of that in commercial environment, not when a government first articulates the orders, even though SpaceX has to adapt to then a great deal.

[bangelo]

SpaceX has rekindled my childhood wonder for what we're capable of; for our ability to precipitate the greatest collective achievements of evolved primates from intangible dreams and relentless determination. I fear my initial post here betrayed my true intention as a simple reality check on our path to a grander future.

Credit where credit is due; landing an orbital booster should be lauded as a fantastic engineering achievement. Fingers crossed this is a step towards interplanetary exploration (a la that one episode of Stark Trek Enterprise). The flight we're currently celebrating is again a fantastical achievement for the sheer logistics involved. All I'm saying is this is technology (so far that's what it is) is still on its way to make tangible changes in our species' exploration beyond earth's orbit and I have a few thoughts and concerns as follows -

1) We've currently matched the performance of the RD-180 on a test stand, where they left off. Arguably this is part of the structure to achieve interplanetary whatever. (we're in 1970 with more advanced materials)

2) I'm extremely wary of the bias towards automation. As a robotics engineer by training and profession I've seen firsthand complications arising from the over reliance of machines and contemporary bias against human capabilities . If the full-flow combustion engine removes barriers to a interplanetary future this, I perceive this developmental philosophy is a setback to those efforts carrying catastrophic potential. We set up the entire Gemini Project to prove we could achieve milestones in orbit (an entire space program) and we still encountered number of issues in the subsequent ventures.

3) Every large-scale space project has been beset, often bested, by dramatic technological failures. Are engineers now somehow more capable then our forefathers? If not, we should expect massive setbacks in achieving truly novel accomplishment and I pray that the good men and women at SpaceX helming this burgeoning revolution overcome them. My fear is private enterprise without government support carries its own risks.

4) The space Shuttle program faced a dearth of expertise resulting from Apollo engineers retiring or otherwise. Poor documentation had us rebuilding lots of technology from scratch. Simply another barrier to overcome in progress.

Finally, what the heck do I know? I'm nothing more than an armchair observer and now a faceless internet pundit. As a somewhat technical Lazy-Boy inhabitant I'm simply voicing my thoughts in the hopes of a rewarding discussion.

-Brandon

[TimTheTinker]

> Spacex only very recently got their closed cycle engine working, the pinnacle of rocket efficiency, catching up to, again, early 1970s Russian technology.

The Raptor is the first functional full-flow staged-combustion methalox engine, and it's already been successfully fired. By some measures, that surpasses both Soyuz technology and the RS-25. Of course, we have yet to see what their true Isp and T/M numbers will turn out to be, but they do plan to use multi-stage (including a refuel in LEO) with separately tuned engines on each. The overall performance (i.e. tons to Moon and beyond) will be very interesting to see.

[bangelo]

How exciting will this be?

[bangelo]

Credit also to reinvigorating the world's interest in space exploration, certainly the driving factor in humanity's explorations efforts thus far.

[m000z0rz]

SpaceX lands and reuses orbital class rockets for real-life missions.