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Comment by forrestthewoods | Hacker News Reader

Is Blue Origin landing a booster that SpaceX is letting crash? Would their forces combined result in total re-use? I'm not sure what all the parts and roles are. Sorry for the dumb question.

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No. At one point, SpaceX has ambitions that they would recover the second stage of their Falcon 9, but then scrapped this idea as too difficult (until their next family of rockets). The reason is that the second stage is going much, much faster than the first stage, so it's a completely different problem to bring it back.

Blue Origins is not trying to get into orbit, and therefore is nowhere close to dealing with the issues that would confront a return of the Falcon 9 second stage. Quite the opposite; from a speed perspective, the Blue Origins rocket is more like an easy version of the already-recoverable Falcon 9 first stage (although as Bezos notes, some of the balancing issues may be harder by virtue of having a smaller moment arm).

I'd consider the goals similar. Both want to land and re-use orbital rocket boosters.

SpaceX landed an orbital booster, but they have yet to re-use that booster. I'm sure they would rather dissect that booster, since they have a factory and are continually building new ones.

Blue Origin landed a sub-orbital booster, and then re-used it. However, this booster is much smaller than what would be needed for orbit. So this rocket is more of a technology testbed (and potential fun ride). They'll have to build and design a whole new rocket in order to reach orbit - and they've already started doing so.

SpaceX is going 10x higher than Blue Origin. They can land on the ground, perfectly fine. They just haven't figured out how to do it on a moving barge, yet. Because launching from Houston means burning extra fuel to put the rocket over land. Fuel that could be used for boosting.

Not just higher, also faster. Much much much faster, to the tune of probably around 9000km/h faster.

Yeah, it's a bit like comparing stopping two cars running max speed into a parking spot with a wall in front: on car being a Bugatti Veyron and the other being a Smart TwoFour. It's certainly impressive to do it in the Smart, but it's rather much a different thing than the Bugatti.

Even that isn't a good analogy, because the speed difference between the Veyron and the TwoFour is only about 2.5x. So maybe if the 2nd car were my bicycle, then we'd be able to make a valid analogy.

To be fair, if you look at the video, you will see that they landed on the moving barge just fine. It was standing still on the platform, stable, with engine disabled.

Of the locks keeping the landing gear in place, 3 out of 4 succeeded. Whoops. Maybe they should simply switch to 5 or 6 landing gears. After all, they went for 9 engines and can boast multiple launches where one or two engines failed (including this latest one. One of the engines shit itself while the rocket was returning to the barge according to the twitter feed).

No, staying standing up is a part of landing. We don't know if that gear failed because of shock forces in landing. "Figure out landing" means "make the rocket survive" not "get the toes touching the ground". I think SpaceX is doing more advanced work, has many more impressive successes than Blue Origin, but ignoring Blue Origin completely, I'm also not going to give SpaceX a pass on their objective failings.

SpaceX is reporting that one of the leg locks failed to deploy, IIRC due to ice buildup while passing through low-atmosphere moisture after reentry. From everything I've read, the landing had a more or less expected touchdown velocity and would have been successful had all four locks functioned as expected.

To be fair, "learned to land" and "did successful landing once" aren't the same things. Similarly, "USA landed on the moon" and "USA now has a capability to land on the Moon" are different things.

And SpaceX will get from here to there faster than the government.

Actually, the altitude is quite irrelevant, the speed is the important part. Given a perfectly round planet with no atmosphere, you could even orbit 1m high.

Don't be pedantic. I'm sure assuming spherical cows we can make super efficient dairy farms. We don't have a perfectly round planet with no atmo. And we don't have rocket engineers who point rockets at the ground. Speed and altitude are practically the same thing.

No, they really aren't at all. The difference between a rocket that can reach 100km and 200km is tiny. The difference between one that can reach 100km, and a 100km orbit, is big.

https://what-if.xkcd.com/58/

They aren't going ten times higher, or launching from Houston. They launch from Florida and California, they are building a launch site in Texas, but its not in Houston.

The Falcon 9 1st stage will get over twice as high on some flights. Then height it self isn't a big deal, it's the extra time in free fall speeding up before it hits the atmosphere.

The big difference, is that the Falcon 9 is heading east at 1.7km/s, carrying as much mass as a fully fueled BO rocket when it stages.

> They aren't going ten times higher, or launching from Houston.

They're definitely going 10x higher (significantly more, in fact). The SES-8 launch saw the SpaceX second stage hit 79,130km - 790x higher than Blue Origin's vehicle has hit.

https://www.reddit.com/r/spacex/comments/1s33mz/ses8_deorbit...

The first stage does not go to orbit with the payload.

They already figured out how to land on a moving barge, and they just did it.

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