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They need to be able to stabilize the rocket's landing in all sorts of conditions if they want to have any hope of landing it on another planet. It's not like

They need to be able to stabilize the rocket's landing in all sorts of conditions if they want to have any hope of landing it on another planet. It's not like interplanetary launches will be able to schedule launches to choose optimal weather conditions for the landing. Maybe, if they're lucky, they'll be able to orbit briefly to avoid bad weather at the landing site, but moderate winds and wind gusts are going to be a problem. If it's impossible to reliably land under those conditions, the whole idea is flawed for the purposes of interplanetary flight. You can't have rockets going to Mars, and only have 50% or 75% surviving for relaunch. That's not the kind of cost reduction that will make interplanetary travel and resupply feasible. It would obviously help with LEO launch costs, though, or any return landings on Earth. Even if rocket stages are only recovered some of the time, and not reliably, that's a significant cost savings and well worth doing. It's just that Musk is so intent on interplanetary travel driving all this technology. If it's only for cost savings for Earth landings, a parachute system or a specially designed (more accommodating) landing complex/barge could work too, right? > (paraphrasing multiple comments) "but this is to re-land rocket stages on Earth" Here's an interview where he specifically talks about his long term goal of landing rocket stages on other planets. He says parachutes negatively affect reusability, I'm not sure how much of that is potential damage or off-site landing and how much is the necessity to reinstall a parachute for the next launch. The point here is that he is clearly not thinking only of Earth landings in developing this technology. I think some sort of assisted landing or more developed landing site could increase chance of recovery and reusability for Earth landings, decreasing total launch costs for Earth orbit missions, at the cost of not being applicable to landings on other planets. [1] https://www.youtube.com/watch?v=SOpmaLY9XdI?t=11m30s https://www.youtube.com/watch?v=SOpmaLY9XdI?t=11m30s

gfodor 12y ago
At the same time, getting to a point where SpaceX has a 10X pricing advantage over there competitors could have a nice effect on their R&D budget for solving problems that may not be immediately applicable on Earth.
daeken 12y ago
> They need to be able to stabilize the rocket's landing in all sorts of conditions if they want to have any hope of landing it on another planet. Well, not really. Dragons (and Red Dragons, for interplanetary travel) are way, way less sensitive to the whims of weather. The issue with the first stage is that you have a very large, very fragile, very bottom-heavy tin can that you're trying to balance on a moving platform. This is entirely different than trying to land a pod, which is what we'll be doing on other planets. Dragon v2 will be landing on land (though doing parachute recovery from water for initial CCS missions, as per NASA spec), and we'll see how stable it is then.
- deleted 12y ago
  [deleted]
  - segacontroller 12y ago
    OK that may be the long term goal, but what is the short term goal? What is the goal of landing this rocket stage on earth? Is it to use this model to land on another planet, or is it to use this model to reduce costs and reuse the first stage of the rocket?
    - deleted 12y ago
      [deleted]
    - _broody 12y ago
      It's the later. Every other possible use of the technology is just speculation at this point.
    - TeMPOraL 12y ago
      Short term and primary goal? Significantly cut down the costs of access to space. But long term goal is landing and taking off from another worlds, and this project produces important engineering insights that may prove useful for that goal. SpaceX has a habit of hitting multiple targets at once.
  - daeken 12y ago
Cshelton 12y ago
I agree, but I think right now, even more important, is getting the model for private space flight/exploration right. Currently, the majority of SpaceX's revenue is through government contracts. Cost savings through reuse-ability should be the number one focus, not the technology on how to land on another planet through adverse and unpredictable conditions. The ASDS is really cool and all, and could definitely be something interesting down the road...like a spaceport sitting right off the coast of a major city, ready to take you to the moon hotel...or the other side of the world in under an hour. But I think achieving major cost savings by landing the rocket in such a way that it could be launched the next day, that should be our first goal right now. Which is why it makes sense to now attempt an over land landing. They had to make sure it wouldn't miss and accidental land in the middle of Miami or something.
- netcan 12y ago
  I'm not sure... Is Miami important to our overall goal of becoming a multiplanetary civilization? I don't see what Miami adds to the mission and I am quite sick of everyone being so precious about it. I have an ex girlfriend from Miami and honestly, I think we would all be better off if we stopped making excuses for her, defending her, covering for her and just let Elon give her what's coming to her!
  - netcan 12y ago
    wow. I guess I overstepped a line. *I don't really have an ex from Miami. Never been there. No ill wishes for the city. ..just to be clear.
    - jccooper 12y ago
      HN does not take well to joke comments. It's not specifically mentioned in the guidelines, but falls generally under "off-topic". Feeling is "this isn't Reddit."
      - mikeash 12y ago
        Especially un-funny joke comments. Of course that line is vague and hard to spot, but I'm comfortable in saying that this particular attempt was way on the wrong side of it. I think it could have been rather amusing if it had stopped about a third of the way in.
benkuykendall 12y ago
Yeah, weather is an interesting point. I wonder if having numerous back-up landing sites worldwide would give a robust enough system.
- danielweber 12y ago
  It's been less than 10 minutes from launch to land, so they know exactly where they are going to land when launching.
vectorjohn 12y ago
Uh, we've already had a few near landings in non-ideal Earth weather. Mars barely has weather. It has wind, sure, but the air on Mars is about 150 times less dense. I.e., it won't be blowing over any rockets. So basically, landing anywhere on Mars is easy compared to Earth if they just find a flat spot.
- cma 12y ago
  That also makes air-braking more challenging. The first stage isn't coming in at orbital velocities, but I'm assuming they are shedding a good amount of velocity using the air?
  - ItsDeathball 12y ago
    The Falcon first stage actually does less aerobraking than a returning capsule. Due to its lack of heat shielding, it's necessary for the first stage to slow its descent with the engines before it hits thicker atmosphere.

gfodor 12y ago

At the same time, getting to a point where SpaceX has a 10X pricing advantage over there competitors could have a nice effect on their R&D budget for solving problems that may not be immediately applicable on Earth.

daeken 12y ago

> They need to be able to stabilize the rocket's landing in all sorts of conditions if they want to have any hope of landing it on another planet. Well, not really. Dragons (and Red Dragons, for interplanetary travel) are way, way less sensitive to the whims of weather. The issue with the first stage is that you have a very large, very fragile, very bottom-heavy tin can that you're trying to balance on a moving platform. This is entirely different than trying to land a pod, which is what we'll be doing on other planets. Dragon v2 will be landing on land (though doing parachute recovery from water for initial CCS missions, as per NASA spec), and we'll see how stable it is then.

deleted 12y ago
[deleted]
- segacontroller 12y ago
  OK that may be the long term goal, but what is the short term goal? What is the goal of landing this rocket stage on earth? Is it to use this model to land on another planet, or is it to use this model to reduce costs and reuse the first stage of the rocket?
  - deleted 12y ago
    [deleted]
  - _broody 12y ago
    It's the later. Every other possible use of the technology is just speculation at this point.
  - TeMPOraL 12y ago
    Short term and primary goal? Significantly cut down the costs of access to space. But long term goal is landing and taking off from another worlds, and this project produces important engineering insights that may prove useful for that goal. SpaceX has a habit of hitting multiple targets at once.
- daeken 12y ago

Cshelton 12y ago

I agree, but I think right now, even more important, is getting the model for private space flight/exploration right. Currently, the majority of SpaceX's revenue is through government contracts. Cost savings through reuse-ability should be the number one focus, not the technology on how to land on another planet through adverse and unpredictable conditions. The ASDS is really cool and all, and could definitely be something interesting down the road...like a spaceport sitting right off the coast of a major city, ready to take you to the moon hotel...or the other side of the world in under an hour. But I think achieving major cost savings by landing the rocket in such a way that it could be launched the next day, that should be our first goal right now. Which is why it makes sense to now attempt an over land landing. They had to make sure it wouldn't miss and accidental land in the middle of Miami or something.

netcan 12y ago
I'm not sure... Is Miami important to our overall goal of becoming a multiplanetary civilization? I don't see what Miami adds to the mission and I am quite sick of everyone being so precious about it. I have an ex girlfriend from Miami and honestly, I think we would all be better off if we stopped making excuses for her, defending her, covering for her and just let Elon give her what's coming to her!
- netcan 12y ago
  wow. I guess I overstepped a line. *I don't really have an ex from Miami. Never been there. No ill wishes for the city. ..just to be clear.
  - jccooper 12y ago
    HN does not take well to joke comments. It's not specifically mentioned in the guidelines, but falls generally under "off-topic". Feeling is "this isn't Reddit."
    - mikeash 12y ago
      Especially un-funny joke comments. Of course that line is vague and hard to spot, but I'm comfortable in saying that this particular attempt was way on the wrong side of it. I think it could have been rather amusing if it had stopped about a third of the way in.

benkuykendall 12y ago

Yeah, weather is an interesting point. I wonder if having numerous back-up landing sites worldwide would give a robust enough system.

danielweber 12y ago
It's been less than 10 minutes from launch to land, so they know exactly where they are going to land when launching.

vectorjohn 12y ago

Uh, we've already had a few near landings in non-ideal Earth weather. Mars barely has weather. It has wind, sure, but the air on Mars is about 150 times less dense. I.e., it won't be blowing over any rockets. So basically, landing anywhere on Mars is easy compared to Earth if they just find a flat spot.

cma 12y ago
That also makes air-braking more challenging. The first stage isn't coming in at orbital velocities, but I'm assuming they are shedding a good amount of velocity using the air?
- ItsDeathball 12y ago
  The Falcon first stage actually does less aerobraking than a returning capsule. Due to its lack of heat shielding, it's necessary for the first stage to slow its descent with the engines before it hits thicker atmosphere.