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Comment by agentkilo | Hacker News Reader

Congrats to everyone involved!

I planned to watch the live stream but wasn't able to. The moment of successful landing was quite modest, only a mostly-static screen with telemetrics was shown to the public, but it absolutely felt magical. It feels like the moon is well within humankind's reach by now.

Coincidentally, I found a copy of Uchu Kyodai (by Chuya Koyama) in my local library, and started reading it recently. It's fun to compare the perspectives from more than a decade ago, to the actual development we have right now, regarding space exploration.

(This was posted to another thread, but I moved it here after I realized comments were moved)

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> It feels like the moon is well within humankind's reach by now.

It has been for the last 65 years. ;)

Yeah that's true, but I haven't really experienced the Apollo era personally. After the "gap" between the old space race, and the new race inspired by private space agencies, I do feel we are getting closer, to the moon at least.

Something most people don't appreciate is that, outside of the distance, Mars is super easy mode compared to the Moon. The Moon has 2 week long nights cycling between highs and lows in the range of -130C to +120C, inhospitable terrain, constantly getting pounded by meteorites, no atmosphere whatsoever, much higher radiation, much less gravity, and so on. Mars, by contrast, is oddly similar to Earth - similar day/night cycle, even a similar axial tilt meaning similar seasonal cycles, relatively reasonable temperature ranges, some atmosphere, and more.

This is why the image of the Moon as a stepping stone to Mars doesn't really make any sense. The Moon is very much 'hard mode', but it's closer. So the main tech issue to make up (long distance travel) is not one that progress on the Moon will go much towards advancing.

Well, Mars is so much farther away and much more massive so you need a lot of fuel if you want to come back. This is much more difficult than the extra fuel needed for the moon landing due to lack of atmosphere. Speaking of which, Mars having an atmosphere means you need complex heat shields for the landing. Furthermore it's so far that unlike the case of the moon you can't make real time adjustments from earth, there's a delay of several minutes. Then again you have dust storms...

Atmospheres make landing easier and require less fuel! A big problem with landing is losing your speed which is going to be extremely high to begin with. On the Moon you can only do this by basically turning around in the opposite direction of your velocity and thrusting an equal but opposite amount. It's not only quite complex but also substantially complicates landing.

This is made even true on the Moon because its low gravity means that even a hair of velocity is going to make you 'bounce' after landing. This is why things like probes and rovers landing (or at least ending up) on their side or even upside down on the Moon is a fairly frequent affair. On Mars (and other places with an atmosphere) you can use atmospheric braking which is essentially just slowing down by bumping into the atmosphere in a controlled fashion. You can even get things like parachutes involved in the process.

The dust storms in Mars are also 'fake' at least as presented in movies/books like "The Martian." Mars has an extremely low atmospheric pressure (relative to Earth) so fiercest dust storm imaginable would feel like nothing more than a slight breeze. The only issue they pose is visibility, and dust accumulating on solar panels. Andy Weir, by the way, was well aware of this when writing "The Martian" which is otherwise a phenomenally well researched hard sci-fi book. I think it's highly telling that he had to intentionally fudge reality to create a crisis on Mars!

I think the big piece that is being overlooked here is the distance. The distance itself poses significant challenges. The obvious things like resupply and communication are much harder. But also the journey to mars is much harder on the human body.

Rescue and abort options are also much harder. The moon is close enough to easily resupply or rescue people on the surface, mars is much harder.

Completely agreed. Distance will impose substantial challenges, but the good thing is that that's really the "only" big challenge there is. I think many people have this mental model where the Moon is easy and Mars is hard, perhaps because we've already set foot on the Moon and so clearly it can't be that bad.

But if somehow both of these bodies were orbiting around Earth, Mars would be just orders of magnitude more straight forward than Mars, and I think it's relatively likely we'd already have permanent outposts, if not colonies, there. So the mental model of it being viewed as a stepping stone is somewhat misleading. The Moon is hard!

And also I don't think the distance will be that bad. We've already had 374 day ISS stays which is far longer than any possible transit to Mars (though nowhere near as long as a late-stage mission abort would entail) and the overall effects of such a stay were not markedly different than significantly shorter stays on the ISS. So it seems very unlikely that even a late stage emergency abort would be fatal.

It's now within reach for a medium sized corporation, largely ignored by humankind.

That's huge progress!

It's not any more or less out of reach for a medium-sized corporation than it's been since the 70s. The reason no corporation has gone is that there's no economic incentives to. And there's still not; this is a NASA mission, it's exploratory science funded by the public.

Since the 70s, costs have gone down by a factor 10-20x, and the technology is much better and safer.

If that made it "out of reach" back then depends on what you mean with those words, but it's undeniably far cheaper and safer now.

How do you expect to get to the Moon before SpaceX? The Space Shuttle ended up costing $2+ billion per launch, and given it's a government program - getting anything on it from an untested company who didn't already have major connections would be near to a nonstarter, and that's even if they could casually foot the billions of dollars it would have cost.

FireFly launched as a private company on a Falcon 9 so their cost was probably a peak of ~$0.07 billion (to maintain units) which may have been able to be privately negotiate downward given the nature of the mission.

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

Smallest lunar lander so far is 200kg/440lbs, that's the weight of a carry on full of lead. Besides the Space Shuttle can't go higher or deliver higher than LEO anyway.

That's not an answer as we're looking for choices available from "the 70s" to before SpaceX so let's say around 2000. This issue is literally why SpaceX was started. Elon looked into NASA's plans for sending humans to Mars, saw they didn't exist and wanted to get the public more excited in space. His idea was to use his money to fund the launch of a greenhouse to Mars, which would be live streamed. No company in America was willing/able to do this, and in Russia the costs were far too high. So SpaceX was born.

You're right that Space Shuttle was a nonstarter for technical reasons, but it doesn't change the core issue. Neither does the mass. Unless you can find other companies willing to share a launch with you, you're paying for a whole rocket. And that's if you can manage to contract a rocket in the first place. As an inconsequential nitpick, no lander weighs 200kg. You're conflating landing mass (of which there's been well smaller than 200kg) with total launched mass. Fuel, thrusters, and so on multiply the weight substantially.

The space shuttle isn't relevant to this conversation. Private industry has been putting things in space for decades, long before SpaceX existed. The reason no private company put a thing on the moon isn't because they couldn't, it was because nobody was paying them to, and because there is not otherwise any economic benefit to them for doing so. If your expected income is zero, it doesn't matter how low your costs are.

I agree that Space Shuttle is not relevant (as a peer poster mentioned it simply lacks the delta v to even get to the Moon), but do not agree that this capability has readily existed for decades. You needed (1) private industry (2) affordable (3) moon capable and (4) civilian availability. We were failing on various points at various times, but now a days none of those really pose an issue anymore.

Now that we've clearly nailed all 4 of those points, we're starting to see lots more interesting things in space from tourists visiting the ISS, people sending their ashes to space, to doing private space walks and going further into space than any human has since the 70s [1], and now even things like this with a private company landing a payload on the Moon. Many of these things are done with no return beyond doing them.

More specifically though, this is also literally why SpaceX was created. Elon was researching NASA's plans for getting men to Mars. They literally did not exist. He wanted to get society more interested in space and so his idea was to launch a greenhouse to Mars and live-stream it. The capability for that simply did not exist in America, and in Russia the costs were far too high. So SpaceX was born.

[1] - https://en.wikipedia.org/wiki/Polaris_Dawn

With US$100 million in taxpayer funding.

Yeah but that didn't pay for the vehicle development.

Fair point.

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