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I realized we didn't have a thread about this yet!
SpaceX made history with the Falcon 9 rocket by having the first stage separate, fly back to the launch pad, and land upright. A giant leap for engineering and the private space industry, and really the space program in general.
It's still going to be years before this technology will actually commonplace. Still, it's pretty fancy.
d-usa wrote: "When the Internet sends its people, they're not sending their best. They're not sending you. They're not sending you. They're sending posters that have lots of problems, and they're bringing those problems with us. They're bringing strawmen. They're bringing spam. They're trolls. And some, I assume, are good people."
It's still going to be years before this technology will actually commonplace. Still, it's pretty fancy.
Science is still cool...
I know it's all still future talk, but will this be something that could be useful for future Mars missions? If we could fabricate fuel and reuse the rocket to return from Mars, would that be a good step towards sustainable missions?
It's amazing the possibilities that open up for us with this. d put forward a huge notion about the Mars missions. Think about the possibilities of planet hopping probes and other such things.
It will be interesting to see what the next ten years of development bring.
Relapse wrote: It's amazing the possibilities that open up for us with this. d put forward a huge notion about the Mars missions. Think about the possibilities of planet hopping probes and other such things.
It will be interesting to see what the next ten years of development bring.
It actually opens up very little. The only thing it does is possibly lower the cost of launches a bit, since you can re-use more of the rocket. And the real market for that is routine commercial satellite launches, where you have a high volume to justify a reusable rocket and there's strong incentive to save money wherever possible.
There is no such thing as a hobby without politics. "Leave politics at the door" is itself a political statement, an endorsement of the status quo and an attempt to silence dissenting voices.
Relapse wrote: It's amazing the possibilities that open up for us with this. d put forward a huge notion about the Mars missions. Think about the possibilities of planet hopping probes and other such things.
It will be interesting to see what the next ten years of development bring.
It actually opens up very little. The only thing it does is possibly lower the cost of launches a bit, since you can re-use more of the rocket. And the real market for that is routine commercial satellite launches, where you have a high volume to justify a reusable rocket and there's strong incentive to save money wherever possible.
I'll have to disagree that it doesn't open up a lot once it's perfected. The cost savings alone gives way to many possibilities and hastens the motivation for further improvements.
The rocket is 90+% the cost of the launch, so even for missions from earth, commercial or exploration, it is a huge deal.
But it really seems like launches from the moon or Mars would be the big deal. Being able to send crews with out having to also send the first stage of a return vehicle with each trip would be a huge logistical benefit and would make travel a lot cheaper.
d-usa wrote: The rocket is 90+% the cost of the launch, so even for missions from earth, commercial or exploration, it is a huge deal.
But it really seems like launches from the moon or Mars would be the big deal. Being able to send crews with out having to also send the first stage of a return vehicle with each trip would be a huge logistical benefit and would make travel a lot cheaper.
Relapse wrote: I'll have to disagree that it doesn't open up a lot once it's perfected. The cost savings alone gives way to many possibilities and hastens the motivation for further improvements.
But money is not really a significant factor if you're talking about Big Projects like a manned Mars mission. We could easily afford to do it with expendable rockets if the political willpower existed to pay for such an expensive project. NASA's entire budget is tiny compared to the blank check we give the military, and a slight change of budget priorities would do more for space exploration than any reusable rocket design. But without that political willpower to make space exploration a priority it doesn't matter if there's a bit of a cost reduction in a theoretical mission that will never be funded.
d-usa wrote: The rocket is 90+% the cost of the launch, so even for missions from earth, commercial or exploration, it is a huge deal.
That might be true for routine satellite launches, but it wouldn't be true for a Big Exploration Project. For example the total cost of the Apollo program was about $20 billion, of which the Saturn V launches were about $7.5 billion (13 at $500 million each). And when you consider that the per-launch cost is not going to drop to zero it the total mission cost doesn't seem to change all that much. If there's the political willpower to spend $100 billion on a modern Apollo equivalent then it probably doesn't matter all that much if there's a +/- 20% difference based on rocket costs.
So, as I said, it's great if you're a corporation that needs to put stuff into orbit and maximize profits, it's less impressive if you're talking about government-funded scientific missions that do more than just boost stock prices a bit for a company.
But it really seems like launches from the moon or Mars would be the big deal. Being able to send crews with out having to also send the first stage of a return vehicle with each trip would be a huge logistical benefit and would make travel a lot cheaper.
Could you explain in more detail what you mean here? Because in pure capability terms, ignoring costs, a reusable rocket is a significant reduction in what you can do. You have to add weight to extend the fatigue life of all of the parts (or there's no point in recovering a used-up rocket that's only good for scrap metal). Then you have to add huge amounts of weight for the fuel required to slow down and make a safe landing. Then you need to add more fuel to carry that fuel. And then more fuel to carry that fuel. And now you need a bigger engine to lift it all, which adds weight and even more fuel required. And so on until you just give up and pay the extra money for a one-use rocket.
There is no such thing as a hobby without politics. "Leave politics at the door" is itself a political statement, an endorsement of the status quo and an attempt to silence dissenting voices.
The fuel is on Mars, the rockets aren't. You can do 10 big round trips to Mars, carrying all the parts required each time and paying all that extra money for every launch.
Or you can pay a little more the first time, and significantly less the other 9 times.
Which is something the scientists working on this realize.
d-usa wrote: The fuel is on Mars, the rockets aren't. You can do 10 big round trips to Mars, carrying all the parts required each time and paying all that extra money for every launch.
Ok, so you go for the "make your fuel at your destination" approach. You now have three choices:
1) Take an expendable rocket, dropping stages whenever convenient, with the return stages packed as cargo and fueled on Mars.
or
2) Take a re-usable rocket, saving some payload capacity (but not the full mass of the one-use stages you aren't taking, since the multi-use stuff is heavier) but now introducing the huge problem that your landing is now more complicated and if anything goes wrong you're stranded on Mars because you broke your only return vehicle.
or
3) Realize that manned Mars missions have little purpose beyond planting a flag and send robots on a one-way trip.
Now, #3 is the pretty obvious correct answer, but if you have to send humans it's far from certain that a reusable rocket is the right way to do it.
Or you can pay a little more the first time, and significantly less the other 9 times.
Which is a good thing, but it's not a decisive thing. It doesn't enable any mission that can't be done with expendable rockets because a reduction in launch cost is probably not going to make a huge difference in the political situation. If the US wants to go to Mars we'll go to Mars no matter what rockets we use. If we don't want to go to Mars it doesn't matter if you say "we can do it for 20% less money" because you're not getting any funding.
There is no such thing as a hobby without politics. "Leave politics at the door" is itself a political statement, an endorsement of the status quo and an attempt to silence dissenting voices.
