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SpaceX returns to flight with Falcon 9 rocket launch (bbc.co.uk)
621 points by thomseddon on Jan 14, 2017 | hide | past | favorite | 189 comments

"A few minutes later, the first stage of the rocket landed successfully on a platform in the Pacific Ocean." - They have made this so normal. Its not even news title worthy now. Exciting times we live in!!

Hell, SpaceX wasn't a trending topic on twitter less than 2 hours after the landing.

Humanity holds the record for the fastest awe to yawn delta.

> Humanity holds the record for the fastest awe to yawn delta.

Among what species?

Cats are still deeply awed by the laser pointer.

I'm sure aliens appreciated the effort longer.

Pretty sure it's just a joke.

Twitter does not represent humanity. Far from it.

Just because something is amazing doesn't mean we need to constantly be screaming about it.

Right, most people have seen this trick performed with a broom handle or maybe even done it themselves. This is the same trick done from edge of space to sea level with a much smaller margin for error and a gravity well.

To me it's fucking awesome. To everyone else it's just a large broomstick.

I came here to write exactly this! Just mentioned in passing, like it's the most natural thing in the world – amazing!

Also impressive to be flying again just 4 months after a blow up (granted it was on the launch pad the day before the launch).

Compared to what was achieved in the 60s it doesn't seem that impressive.

With unlimited money almost any engineering problem can be solved. It isn't a miracle men walked on the moon, we just decided to go.

>Compared to what was achieved in the 60s it doesn't seem that impressive.

Is all of computing since 1960 unexciting and pointless? It's just making computers faster and cheaper, so what? The internet? We already had networks, who cares? It turns out that scale matters. Cost matters. Access matters. Details matter. If you can't see the value of treating rockets more like airplanes then you have a small-minded worldview and I don't know what to tell you.

History is littered with inventions that didn't amount to a hill of beans until someone else found a way to turn that invention into an awesome product and sell it to a much wider audience.

When a trip into orbit costs $20,000 then a lot more people can go. When it costs $2,000 then anyone in the developed world can go. What impact that will have on our society?

With unlimited money almost any engineering problem can be solved.

A lot of them can be solved. Knowing which ones can be solved economically is the whole point of Elon Musk's First Principles approach.

(I should apply first principles to games and simulations.)

>When a trip into orbit costs $20,000 then a lot more people can go. When it costs $2,000 then anyone in the developed world can go. What impact that will have on our society?

Are you seriously implying that landing a rocket is an unprecedented step in that direction?

Do you think something like this would have been impossible if people had set their minds to do it, in the 60. I don't think so. I mean, we had missiles that could follow and destroy jets moving faster than a bullet...like, I don't know, 30 years back? Exactly that is why I think this is just marketing and PR (Not the actual stuff they are doing, but how it is seen and projected)...

>Are you seriously implying that landing a rocket is an unprecedented step in that direction? >Do you think something like this would have been impossible if people had set their minds to do it, in the 60.

It would have been impossible. They just didnt have the materials science to build lightweight engines, fuel tanks, landing legs and such. The computers needed to control the rocket would have been the size of a large building and have to be on the rocket to be responsive enough. Remote control wouldn't have been an option. Also GPS didn't exist and no contemporary positioning technology light enough was up to the precision required.

The 90s is another matter. The DC-X was pretty much a direct ancestor of the SpaceX and Blue Origin plans. Still, it would have required a manual or remote control landing, which would be horribly inefficient compared to an entirely computer controlled 'suicide burn' landing. Even so there's a world of difference between being able to do something and actually doing it.

I don't know if they could have reduced costs as agressively in the 60's. The market was then smaller and making things more expensive (as the world population was smaller and productivity was lower than today). I don't know if this matters though. I'm sure soviet russia could have manufactured space tourist busses in stead of all the nukes and launchers they did as they played by a bit different economic rules. That would have been awesome. Instead we got just an opportunity for thousand megadeaths.

Yes it is. The rocket costs 15 million. The Fuel is 200 thousand. Getting the rocket back is a huge potential realization in cost efficiency.

What was achieved in the 60s built on what had come before. Goddard worked out the principles of liquid-fuel rocketry in the 20s and 30s, John Clark (and presumably others, but he wrote the book) developed rocket fuels in the 50s and 60s, and Von Braun took Army money to build large rockets based on science other people had worked out between 1940 and the 1960s. Setting aside a certain amount of arguing about whose developments were more important, it's probably safe to say that most of the impressive developments of the 60s were actually developed earlier.

Well, why stop there? Could Goddard have powered his rockets without chemistry that was developed in the 1800s?

Literally all science is built incrementally on previous discoveries. In the words of Isaac Newton, "we stand on the shoulders of giants".


That said, SpaceX certainly isn't doing anything more than an incremental improvement on previous ideas, of course. Even the Space Shuttle used refurbished boosters, this is just the same idea with a much faster refurbishment cycle.

Well why stop there? The origin of the cosmos...

Newton's remark was mostly a backhanded slur against Hooke, as far as can be told. If you can point to some novel development in rocket fuel or rocket engine engineering of the 1950s that somehow contradicts my account, I am sure that I would be grateful of the correction. I wasn't alive then nor am I a particularly good scholar. But I did read Dr. Clark's book, which I understand to be the authoritative work on the subject, and the distinctions in the persons and nationalities involved in the periods in question do seem to be fairly distinct. Von Braun acknowledged the influence of Goddard explicitly, and the post-war and pre-Mercury/Apollo era of rocket science does seem to be quite an interesting one both scientifically and politically. As far as the fundamental science of rocket fuel goes, yes, there is unfortunately not much further to be done, but every science has noted limits to efficiency. But if I may repeat myself somewhat, the point was not that there had been prior art, but that nothing particularly important happened in the 1960s. There are only so many chemical reactions that are suitable for liquid fuel rocketry, and -- pertinent to the news event -- SpaceX is going down a very well-worn thermodynamic road with these rockets. So the impressive point, the reason that anyone is giving these people business, is not that they have any sort of greater chemistry-related insight than anyone else, but that they are planning on re-using enough components to drive launch costs down. But they haven't actually done that yet. They have yet to re-use anything but the barges. So perhaps in that sense, one could consider the achievements of the 60s and SpaceX to be equally lackluster, but otherwise it seems like a poor comparison.

> Newton's remark was mostly a backhanded slur against Hooke, as far as can be told.

Could you expand on that? I am aware of the feud between the two, but I fail to see how this insults Hooke.

Basically Hooke was short, so he Newton was backhandedly saying he didn't get his ideas from him. Since then it has acquired a secondary meaning apart from the insult.

I knew he was insulting someone! For all I have read Newton seems such an a uppity give credit to none asshole that that phrase always has struck me as completely out of character. Now, if he was dismissing a competitor...

Thank you, nice twist!

I hate to smash this concept, but if you'd bothered to read the link I provided:

> This has recently been interpreted by a few writers as a sarcastic remark directed at Hooke's appearance.[8] Although Hooke was not of particularly short stature, he was of slight build and had been afflicted from his youth with a severe kyphosis. However, at this time Hooke and Newton were on good terms and had exchanged many letters in tones of mutual regard. Only later, when Robert Hooke criticized some of Newton's ideas regarding optics, Newton was so offended that he withdrew from public debate, and the two men remained enemies until Hooke's death.

And hopefully magnitudes less expensive refurbishment. That was what really killed the orbiter/shuttle program.

Given that, what great achievements in space we have pulled off in the 2010s when so much hard work was done before?

I'm going to break with the pack and say you are quite right. By itself landing the boosters isn't a dramatic achievement. After all they're not even manned.

But it's not about landing the boosters, it's about what this will enable in the future. If Musk really can reduce the cost to orbit by a factor of 100 it will revolutionise space transport. Imagine a series of moon landings just like in the 60s and 70s, but all using the same launchers and spacecraft? How about manned missions to Mars in reusable ships? It's the first step in a new era. So ok it's not headline grabing next to the moon landings. But compared to that, the Mercury missions don't look all that much of an achievement in hindsight. Yet they were vital groundwork.

I mean, from an engineering perspective it's pretty dramatic. The rocket is going two kilometers a second in the wrong direction, it has to null out that speed, hit a moving target in the middle of the ocean and come to a stop. The rocket is too light to hover (the engine can't be throttled low enough, it's too powerful) so the velocity must be zero'd out right at the deck, too early and the rocket starts moving back up, too late and it hits the boat and blows up.

The economy factor is the main point here that many seem to be missing. SpaceX has already more than halved (and in some cases quartered) the cost of sending satellites into orbit. Heck, even NASA is finding it cheaper to contract satellite launched to SpaceX, and several countries who wouldn't previously have been able to afford to send their own hardware into space are now finding it viable.

For all of the marvellous things done in the 60's space program, we are now half a century down the track from that and things were still expensive with a lot of throwaway hardware. The orbiter (shuttle) program never really delivered on the reduced cost it promised. It has really only been in the past decade or so that private industry has taken up the reins and pushed the technology for more cost effective space travel.

Yeah, I agree. It's not the technology that's awesomest but the economy model it facilitates.

No one was landing booster rockets again after launch in the 60's...

NASA did operate the STS throughout the 1980s, 1990s, and 2000s though, which landed and re-used, albeit expensively, the orbital space-plane component.

Letting bulk cylindrical metal shells slam into the ocean is a bit less sophisticated than tail landing a liquid fueled rocket. Landing the orbiter was a technical tour de force, but the effort went into increasing cross-range, taking away from the economics.

Nasa was landing and reusing the main engines of an orbital launch system is the early '80s. SpaceX hasn't actually reflown anything yet - the landing is cool and all but it's a pointless stunt unless and until they can actually refly the boosters they've landed.

Sort of. The Shuttle was reusable only in the loosest sense:

- Most of the launch tankage was discarded after each flight

- Boosters were basically rebuilt after each flight

- Cost per pound to LEO wasn't remotely competitive with 60s vintage expendable systems like Soyuz

SpaceX has a new, simpler and much better design. Even when flown fully expendable, the F9 is highly cost competitive. With the first stage landing, most of the launch tankage and 9/10 engines can be reused.

SpaceX is poised to dramatically reduce the cost of going to space for the first time since the advent of spaceflight.

> The Shuttle was reusable only in the loosest sense

I specifically mentioned the main engines. And we can't really compare with the F9 when, once again, it has never been reflown. A lot more of the Shuttle was intended to be reusable than ended up being the case - who's to say how that will play out for the F9?

> Cost per pound to LEO wasn't remotely competitive with 60s vintage expendable systems like Soyuz

Soyuz is an excellent system, but it didn't have anything like the lift capacity of the Shuttle. The Shuttle wasn't cheap, but it was designed for a particular set of requirements - some of them reasonable, some of them less so - and for a much higher launch rate than actually happened, for a variety of reasons.

I specifically mentioned the main engines. And we can't really compare with the F9 when, once again, it has never been reflown. A lot more of the Shuttle was intended to be reusable than ended up being the case - who's to say how that will play out for the F9?

The shuttle main engines required a lot of maintenance and inspection after each flight. That's to be expected at the start of a program, but they never got away from that.

Ya sure, landing booster rockets is a way bigger deal than sending men to the Moon.

Both of them are big deals. Landing on the Moon was a historic event, the first (and unfortuately one of the few) time a human being stepped onto something that is not the earth. That is a one-time historic landmark to be listed in history books from now on.

Landing rocket boosters is a very big deal in practical terms as this should reduce the cost of going to space to a point where it becomes more accessible. The shuttle was an attempt to achieve the same, but while being a technological marvel, it failed to reduce costs (quite the contrary) and was abandoned. Everyone else so far at best managed to keep the cost of one-time use rockets low, but SpaceX should have a break-through there, and that is why this matters so much.

Some might argue that having an unlimited budget, and nearly a million people working on a project, and utilising 'throwaway technology' would be arbitrarily easier than trying to do it with private funding.

Moon travel is not a common everyday thing now, because the original effort wasn't geared for that - it was primarily to put a man on the moon as fast as possible, before the Russians did it.

If the aircraft industry worked the same way and airlines had to throw away a 747 after each flight, it wouldn't be an every day thing like it is now.

SpaceX are essentially setting up the future building blocks for far more affordable and common space flight now. It is a longer path, and IMO no less difficult than what NASA was doing back in the 50's and 60's.

>SpaceX are essentially setting up the future building blocks for far more affordable and common space flight now.

What exactly is the breakthroughs/discoveries that Spacex have made that will justify the claim.

Please note that landing the rocket does not count. Because I don't think it involved something new, some new technique that was unknown before.

Well, despite what you think landing the rocket was a breakthrough. Sure it involved the application of standard techniques in the industry but a combination so executed becomes more than the sum of its parts.

If you want something where SpaceX has blazed trail in science as well as engineering then there's thir work on CFL and more importantly supersonic retro propulsion. It turns out that the bow shock created by the engines is enough to serve as an ersatz heat shield and it protects the rocket when it would otherwise be destroyed during reentry. NASA's studying the data they've recorded for the purposes of applying it to Mars EDL. It's given them a chance to investigate an entirely new EDL technique which is important seeing as the Low-Density Supersonic Decelerator seems to be going nowhere.

>bow shock created by the engines is enough to serve as an ersatz heat shield

Source pls. Google search yeilds no results.

It's an over-reach of me to say that they discovered it. This talk gives a good outline of SRP. https://youtu.be/GQueObsIRfI?t=983

>What exactly is the breakthroughs/discoveries that Spacex have made that will justify the claim.

The breakthrough is actually doing it. A lot of space engineers were saying before Falcon 9 that what SoaceX were trying to do was impossible.

Hindsight is 20/20. It's easy to see now what steps were required to pull this off and that clearly those steps were possible. But if it's so clear, why wasn't it done before? The ottoman line is only Must and SoaceX were prepared to get the job done. Nobody else was even trying.

>The breakthrough is actually doing it...

That is not a breakthrough.

Not all breakthroughs are just theory. If you can show me someone actually managing to land a launch-capable rocket, and not just some testbed demo capable of throttling to less than hover, I'm all ears.

The only other player in this space is Blue Origin, and they are still working on their commercially-viable engines. Everybody else throws away their rocket after the launch.

> If you can show me someone actually managing to land a launch-capable rocket, and not just some testbed demo capable of throttling to less than hover, I'm all ears.

Are you saying only SpaceX is capable of doing this? Seriously?

Are you saying that only USA were able to put a man on the Moon in 1960-s? Seriously?

No. That would be an utterly moronic claim if someone made it..

Here's what they actually did that was novel:

- Building an engine capable of multiple restarts while facing into a supersonic headwind, which are necessary for any kind of successful propulsive landing.

- Designing a mass-thrifty first stage simultaneously lightweight enough to be able to accommodate the added weight of landing equipment, but strong enough to handle the tensile stress and buffeting of atmospheric reentry.

- Developing ultralight landing legs to enable stable landings at low mass cost.

But most of the innovation has been in the realm of integrating existing technology in new ways. They brought together cold gas thrusters, grid fins, and thrust vectoring - none of which were new - into a complete package capable of precisely controlling the flight of a 15-storey first stage from the upper atmosphere to the ground. It's the act of getting technologies to work together that is often the source of the greatest gains.

[edit for format]

> Please note that landing the rocket does not count. Because I don't think it involved something new, some new technique that was unknown before.

"Answer my question despite my imposition of arbitrary criteria that intentionally make it unanswerable"

Landing the rocket is the first step in figuring out reuse. Its irrelevant that it probably did not involve some scientific breakthrough - in fact it makes it all the more sadder that no-one bothered to do it before. Same situation with Tesla. No breakthroughs there either. Now imagine all the things we can do right now but aren't because no-one is interested in funding it.

If you arbitrarily dismiss things because you "don't think it involved something new" that's a fairly random criteria.

Their unique breakthrough is relighting rocket engines in a hypersonic airflow. Everything else is shoulders-of-giants and design iterations and good project management, but relighting rocket engines like that was an unknown.

Landing is a critical prerequisite to reuse: we can't reuse what we discard.

But the important reusability breakthrough comes in a few months when they do the first reflight of an orbital booster.

Actually there was a lot of new stuff learned especially in the transonic regime.

> Ya sure, landing booster rockets is a way bigger deal than sending men to the Moon.

I don’t think anyone is claiming that. They’re both impressive feats in their own right.

Yea even though I was not born then, I can imagine. It shattered lots of long held popular beliefs and took mankind to a whole new level.

How much did the work in the 60s cost? I imagine it was multiples of what SpaceX has spent.

I don't know what they did on the camera and transmission side, but having the sub-orbital view on the 1st stage all the way down to the barge was super impressive.

This. I found that so satisfying to watch. I was also pleased that the broadcast team made an on-air comment congratulating their colleagues that got that working.

It helps that the broadcast team is comprised of the more photogenic engineers.

I'm curious to find out what they changed. One of the problems they previously had was that the vibration from the rocket landing was too much for a satellite connection on the barge (or it's nearby support ship); there were other issues on the rocket. Maybe being right next to the coast the whole time helps on a polar launch?

Well, vibration of the barge wouldn't have been a problem this time as there was no view from the barge during the landing (only after). But I had the same thought regarding the launch profile to be much easier to track. GTO launches from the East coast are about 600 km off the coast. This time the drone ship was about 370 km away from the launch site, and also much closer to land in general.

We'll see how it'll be for the Echostar 23 launch (and landing).

> Well, vibration of the barge wouldn't have been a problem this time as there was no view from the barge during the landing (only after).

There was a live view from the barge on the technical stream through descent.

The issue with the last few was that the barge was over the horizon from the high bandwidth stations receiving the data from it. The vibration is certainly a factor, but it causes more of what you saw on this launch, artifacting, rather than a full disconnection of the feed.

> It helps that the broadcast team is comprised of the more photogenic engineers

John Insprucker is far more of what you'd expect of a typical engineer. Reddit r/SpaceX went wild for a few minutes when they saw he was back doing the live broadcasts. People like his authenticity.

The engine exhaust ionizes the air as well, which can be a problem from what I've heard.


Here's a photo I took of the ascent from about 50 miles east.


(Nikon D7000, 300mm, handheld. Cropped and adjusted for contrast.)

Here's a few I took 3.9 miles away...with a much cheaper camera. (:

https://www.realms.org/pics/spacex/IMG_1152.JPG https://www.realms.org/pics/spacex/IMG_1158.JPG https://www.realms.org/pics/spacex/IMG_1195.JPG https://www.realms.org/pics/spacex/IMG_1205.JPG https://www.realms.org/pics/spacex/IMG_1208.JPG https://www.realms.org/pics/spacex/IMG_1209.JPG

It was extremely loud. It was my first launch, and it was surprising. You could feel your chest rumbling, and the car I was standing next to was visibly vibrating.

Freaking amazing experience!

This is where we were standing: https://goo.gl/maps/1eAurqSuD722

> "The best zoom lens is your legs"

Very cool! One of these days I'll get out there for a launch. Did you come down just to watch it? Must have been need to be with all those other people.

Yup, we drove down from Mountain View the night before.

We did stop by Solving on the way back, which was pretty fun.

Impressive. The flame looks about 4.6 times the length of the rocket (measured with the edge of a spoon equaling the height of the rocket) and about 4 times its diameter at the flame's base. Falcon9 is about 70m with a 4m diameter? This makes the trailing flame 322m long and 16m wide at the base.

Imagine an erect column of fire with a 16m base that goes up 322m... That'd be an awesome thing.

Nice picture; could you hear it from that distance?

(I'm very jealous; I'd love to see a launch, but neither Switzerland nor the UK have functioning space programs, and French Guiana is a bit far too walk...)

Thanks. I've been able to catch a few launches over the years. (I even heard the Shuttle's sonic boom once.)

I didn't hear it going up but there was a loud rumble on the return. (Which I couldn't see from my vantage point.)

Are you accounting for the speed of sound? The distance to the launch site of 50mi would be about 4 minutes of delay (getting longer as it flies South)

Hearing the landing over 400km away (or even boost back burns which started about 4.5 minutes and several hundred km down range, plus whatever altitude it attained) seems odd if you didn't hear all 9 engines going up.

Oh, yeah. You're likely right. I wasn't keeping close watch on the time as I had my hands full with a radio, live stream on my phone, and the camera.

Ism not the original person, but I live in Santa Barbara (about 60 miles away). You can definitely hear the rumble, delayed by several minutes. The launches at the middle of the night are the best since it's so quiet.

Come to Florida. Plenty of launches there year-round! And lots of places to stand and watch. Can take a tour of the complex before or after as well. It's truly a great experience!

For those wondering, they successfully deployed all 10 satellites, after the second SECO, into their correct orbit.

They said they might have video of the deployment, but this was interupped by the loss of ground tracking. Anyone know if that video will ever be available?

SpaceX is inconsistent about what videos they provide after a flight. They'll usually pick one or two that are good from a marketing perspective. (New and/or impressive.) I wouldn't be surprised to see an edited Vine of the satellite deployments, though.

I actually would be pretty surprised, since Twitter axed Vine a few months back...

They have released videos of RTS crashing etc. so they have been pretty up front about everything

That might not be totally true. The US govt likes to sneak secret things into comm satellites. For example gps satellites also contain hardware to detect nuclear detonations and track missile launches.

Just speculation, but there could easily be earth viewing spy telescopes, wide band radio capture, or space weapons tacked on these

> The US govt likes to sneak secret things into comm satellites. For example gps satellites also contain hardware to detect nuclear detonations and track missile launches.

Umm what? GPS satellites are not commercial satellites, they're owned and run by the USAF... every aspect of their design is protected by TS and TS/SCI clearance. The master GPS satellite control station is a USAF base in Colorado. They can put as many extra DoD supporting features on them as they want without "sneaking" anything.

Well, I would expect those mostly in military / govt satellites (even those with more benign overt goals such as the GPS constellation). Sounds a bit less likely that they would sneak military hardware (specially weapons) on comercial satellites owned by a private corporation (i.e. Iridium Communications) and likely not designed to function in an adversarial environment. I mean, it is a VA based company, so it is possible, but would not be my first bet. Lacking ground tracking when the satellites are deployed almost a half-orbit away from the launch site seems perfectly plausible to me.

This was a private launch of commercial satellites (Iridium) whereas GPS is run by the military. In the past, missions with classified satellites do not feature any publicly available footage or telemetry at all.

I guess that's impossible to rule out that this is a sophisticated plan to hide even the existence of the classified microsats, while providing detailed footage and telemetry up until the moment they are deployed, but it's far-fetched.

When Iridium went out of business the Pentagon stepped in to run it[1], just sayin' :-)

[1] http://abcnews.go.com/Technology/story?id=119255

Except that they didn't. They just offered a nice fat contract to keep it afloat. TFA: "Staving off a fiery end to the 66-satellite necklace and its spares, the Pentagon on Wednesday awarded a projected two-year, $72 million communications contract to seal a new ownership deal worked out in a New York bankruptcy court."

That's like claiming that NASA is "running" SpaceX, since its contracts are extremely important to SpaceX's business model.

Fair enough, that said, if your biggest customer and source of 99% of your revenue said, "Hey, we want you to put a special something on your satellite the next time you fly one..." do you think they would say "No way!" ? :-) Not saying they did or they didn't but if they asked I'm sure Iridium would have accommodated any request from the customer.

Edit: Iridium would have accommodated their customer.

I agree with you. Many defense contractors already do this. We've seen it most in telecoms post-Snowden. There are secure phones based on Iridium's tech. There's no reason to think they aren't getting some kind of side benefits out of the leverage they have. They usually try & often get it.

Unfortunately most of HN doesn't :) , the downvotes brigade is strong on this one. I'm not normally a purveyor of conspiracy theories but to me this seems like the most obvious reason why the rest of the launch would be not only filmed but Livestreamed, with no footage of the sat deployments

Conspiracy theory style speculation doesn't do well on HN. I can buy the conjecture that comma satellites might be tapped for intel. It's pointless and groundless speculation along the lines of mud slinging so expect downvotes, but at least it's not completely implausible. But the idea that space weapons might be sneaked onto non-classified satellites not covered by military level security standards makes no sense. Why would the military expose themselves to security risks like that? It's pure BS.

Im not pushing a specific hypothesis so much as saying there's a recurring pattern of subversions and fringe benefits to deals like this. Usually for a lot less money, too.

Apparently Thales is involved in the construction of the iridium sats. Would quite risky for the DoD to expect secrecy when construction is made by a european, mostly french, defense contractor.

US does not share its intelligence data openly with european countries, the only exception being UK.

If anyone would care to share I would be interested in understanding the negative interpretation of this comment.

The way I interpret the comment is that the Pentagon bankrolled Iridium with a $72mil contract, and that therefore Iridium is likely to respond favourably to Pentagon requests to quietly add a little something extra to their satellites.

I'm not sure if that interpretation is negative or not, I guess it depends on whether you approve of the Pentagon and its intelligence gathering activities.

Why bother? Couldn't the American military just launch their own satellites instead?

Curiouser and Curiouser.

Sadly, with these new Iridium satellites, the 'Iridium Flare' phenomenon of a bright flash visible in the sky when the old satellites passed through sunlight and reflected it downwards when overhead, will no longer occur. I liked the quote from the Iridium CEO explaining why it won't happen: "[...] we weren't going to spend money just to make angular shiny things on our satellites [...]"

That's news to me, and a real disappointment. Just before Christmas I saw there was going to be a mag -8 flare close to where the ISS would be- watched it with my 4yo, spinning a tale the ISS was Santa and the flare was a reindeer re-entry.

The flare predictor[1] on the Heavens Above website will presumably shut down when the last of the old satellites goes.

[1] http://www.heavens-above.com/IridiumFlares.aspx

The video says a one engine burn on the return of the first stage. The descent seemed a bit slower than the last landing and thus less of a dramatic suicide burn.

This time the descent video seemed more "real". On the last barge landing it was so quick that it seemed magical.

The descent _was_ slower. This was a launch to low earth orbit, as opposed to the geosynchronous launches we've seen recently. Geosynchronous launches require the first stage to be going a lot faster by the time it separates (thus requiring the three-engine landing burn).

If you are thinking of the same landing I think you are, the broadcast glitches caused some of that "magic" feeling.

The broadcast glitched out and when it came back the rocket had landed. The timing made it seem like it really slammed down, but if you look at a simulation of how fast it was really going, it looks a lot less "magic" (although still crazy impressive!)

Recent discussion on the webcast: https://news.ycombinator.com/item?id=13399119

Good for them! I'm impressed with how quickly they were able to conclude their accident investigation and get approved for return to flight. Brings to mind all of the multi-year Shuttle accident investigations.

In fairness, if there had been loss-of-life it probably would have been a much harder process.

I suspect the reason for the swift return to flight is half that fact, and half that SpaceX is more bureaucratically efficient.

To be fair, there was no loss of life in this incident.

If it were to have happened on a manned flight, even with nobody was on-board during the test, then I doubt we'd be seeing return to flight so quickly.

Watching the broadcast, it appeared that they launched _westward_ off the coast of California. That seems very weird to me, since my understanding is that you can use the not-insignificant rotation of the earth as "free energy" to achieve orbital speed.

Did they launch westward? Why?

Iridium sats are in polar orbits. Launches for those inclinations are done from the west coast due to geographical constraints. Also, I believe it makes them travel "backwards" to other (most?) sats.

Well not so much "backwards" as perpendicular.

The target orbit is a polar one. For those you actually have to cancel that "free energy".

Close. In this case, they launched mostly south. Vandenberg was created to give the US a polar launch capability. You can't launch southbound from Florida, as the launch would pass right over Miami.

Well you could, if you were reckless, like China... Have you seen the videos of a failed first stage that fell on a village about 10+ years ago?

Neat! Thanks! It was an artifact of the rendering that made it look westward, but I can absolutely see how it could have been South. Makes sense!

The satellites need to end up in a polar orbit (i.e. they need to be moving directly north or south). So they launched south and slightly west - just enough that the westward thrust would cancel out that "free energy" from the rotation of the earth.

It would have been cool to see an animation of how these seven satellites move in their orbits (as well as the final completed constellation).

Well, the final completed constellation would look something like the video in [1] which is available at the Iridium website [2]

[1] https://youtu.be/sXUmBJmf_DI

[2] https://www.iridium.com/network/iridiumnext

And the beauty of this is, launching these Iridium satellites is just a beta test for what they're going to do next: launch _four thousand_ of their own satellites which will blanket the planet with gigabit broadband.

I wouldn't call it a beta test. These launches provide crucial income for the company.

One does not preclude another.

This was freaking amazing. These are the types of technology launches that truly get me excited.

What's awesome is watching the commentators trying to hold back their excitement a bit. Awesome job SpaceX!

Why does Space X land on barges while blue origin land, well on land. Also does anyone have a pictures of iterations of Space X's landing methods and strut setup?

SpaceX launches stuff into earth's orbit, and to enter orbit you must be traveling very fast horizontally -- it is not enough to merely escape the earth's atmosphere by ascending vertically. The first stage travels hundreds of miles 'downrange' of the launch site (as well as up) in order to achieve the required horizontal velocity. Most orbital launches are aimed over an ocean, so that if something goes wrong the fiery bits don't land in a populated area, hence the need for a landing barge.

If the first stage were to "fly" all the way back to land after separating from the second stage, that would require some combination of a heavier/stronger rocket to hold more fuel, and a reduced payload capacity to orbit.

Blue Origin only does short, up-and-down flights -- they are not trying to achieve orbit so there is no need for horizontal travel. They can simply shut off the rocket and fall back to the launch site.

> If the first stage were to "fly" all the way back to land after separating from the second stage

You write it as a hypothetical, but that's actually how SpaceX landed their first first booster. It was Falcon 9 Flight 20, which deployed 11 Orbcomm satellites.

Infographic of the trajectory: https://i.imgur.com/D9BdO86.png

Interestingly, NASA also considered that as a potential abort mode for the Shuttle ("RTLS" - return to launch site). Minus the vertical landing of course. It was the first option that would be available in the event of a failure, immediately after SRB separation. The vehicle would execute a Powered Pitch-Around maneuver and then jettison the external tank, timing things so that they would run out of fuel and the vehicle would have its proper CG for gliding.

The astronauts considered it extremely risky to say the least. NASA actually wanted to try it on STS-1 (a manned flight on a system that had never been tested before) to see if it worked. In the words of the mission commander: "Let’s not practice Russian roulette, because you may have a loaded gun there." Which carries a lot of weight from a man who was willing to risk a lunar landing.



Previous HN discussion: https://news.ycombinator.com/item?id=8447479

Thanks for sharing that infographic. I was literally just wishing I had some way to visualize the trajectory when I read your comment.

Yep - it mostly depends on the available fuel left over after the orbital insertion. Not an option on all missions.

Blue Origin does not launch into orbit. Going up is the 'easy' part. To get to orbit you have to go many thousands of miles per hour sideways. Blue Origin doesn't go sideways at all, they just go up and come back down.

SpaceX has done 'land' landings in the past as well (for lighter payloads they have enough fuel to turn around and come all the way back to land).

EDIT: Here's a quick explainer on the topic with shiny graphics: http://www.popularmechanics.com/space/rockets/a18711/blue-or...

It is pretty easy to learn the difference in this with a very basic rocket in kerbal space program. Launch up and you'll come down near where you started, in a parabola... Launch up and then go sideways to gain orbital velocity for a long time, you're in orbit.

Agree, KSP is a great way to internalize how orbital mechanics work. After playing it a little while, everything clicks and things become natural, like the sort of physics one uses playing billiards or building block towers.

In this case it would have been barely possible to do a land landing, but the margin was much larger for a barge landing (since the stage doesn't have to return all the way to the launch site, which takes quite a bit of fuel). In the end it doesn't really matter, though. The cores that land on the barge just take a few days longer to return home.

Droneship landings are particularly convenient for west coast launches, as they can unload them ~20 miles from the factory (which is where they are refurbished, for now at least).

Relevant (what-if)xkcd: https://what-if.xkcd.com/58/

Others have answered your question about landing on land. So I thought I'd just link the pictures you asked for.

The initial (publicly shown) iteration was Grasshopper, it looked like this [0].

After that there was F9R-Dev, which looked like this [1] (it's pretty much just a F9 first stage). At some point they added grid fins, which look like this on the vehicle [2] and this up close [3] (note the anti-pidgeon spikes are being added purely for display, they are not attached during flight). Other than that there haven't really been any visible iterations, the legs look like this [4] and have since the F9R-Dev.

[0] http://spacenews.com/wp-content/uploads/2014/11/Grasshopper_...

[1] http://i.imgur.com/ZTpp8pP.jpg

[2] http://www.spaceflight101.net/uploads/6/4/0/6/6406961/518499...

[3] http://spaceflightnow.com/wp-content/uploads/2016/08/SPACEX-...

[4] https://i.stack.imgur.com/YXCrb.jpg

SpaceX can and will land on land when the mission allows it. See ORBCOMM-2: https://www.youtube.com/watch?v=ANv5UfZsvZQ

Blue Origin's mission allows it because it's suborbital. That is: it doesn't actually go anywhere other than straight up. That's also why they can launch in the middle of Texas.

Because SpaceX goes to orbit and Blue Origin doesn't.

One thing others haven't mentioned is that the Falcon 9 is probably something like 10x the empty mass (or more) than the vehicle Blue Origin has demonstrated. As others have said, it's also going higher and much faster, and accomplishing the landing in addition to (and secondary to) launching a real commercial payload into orbit, which AFAIK Blue Origin has never done.

Blue Origin's accomplishments (especially their engine designs) are nothing to sneeze at, but SpaceX is currently in a completely different league. The fact that they have to land on a barge is a result of how scaled and practical their technology is; that they succeed in doing so is an unprecedented achievement in launch vehicle technology.

Two issues I remember hearing - there's a much larger launch window for landing on the ocean barge and something regarding approval/ regulations being more stringent for a land launch. Blue Origin's test flight didn't go too high so it didn't face the same issues.

I may be completely wrong here but I'm fairly certain that's what I remember reading.

Yeah you're wrong, it's to do with the speed they are travelling to get the launch trajectory, they lack the fuel required to make it back to land

It has nothing to do with the height. Both rockets go 'up' a similar amount. The difference is how far sideways Falcon 9 has to go (since it is launching a payload to orbit).


Have Blue Origin gone 'up' further than ~100km ?

They're in that ballpark. I know the capsule exceeded 100km. I don't know if the first stage technically broke that or not, but it was closer if it didn't.

I think SpaceX are in a much higher ballpark?

Not really... A few dozen km altitude difference doesn't mean a whole lot. The _much_ more significant difference is that Falcon 9 is traveling sideways at several times the speed of sound. New Shepherd is "just" going sight up and coming back down.

Just to add to the discussion - Blue Origin don't land on land yet, but when they start doing orbital launches with New Glenn, they will have to.

IIRC Blue were sitting on some "landing on a barge" patents that SpaceX successfully fought, because they were far too obvious.

SpaceX has landing pads (see LZ-1 at the Cape) on land as well, and used one for a successful landing already. For the Falcon Heavy launcher there have been plans reported for two, or maybe all three, of the stage one cores to return to the launch site and land there.

They use the barge as they are firing much harder than blue origin and don't have the fuel to make it back to land

And what a beutiful launch & landing it was! I gotta admin, I was a bit nervous after their last explosion. Great everything went smoothly!

It would be really cool if there will be a recording of "arriving to Antarctica" from stage2 https://youtu.be/7WimRhydggo?t=3012

Any videos of the landing?

Thanks --- this one's the technical webcast and not only gives you a much better view (mostly side-by-side streams of the video feeds from the two vehicles), but there's no commentary and the audio feed's from mission control.

No onboard ascent footage or fuel tank footage this time, alas.

I read a while ago that they were restricting the fuel tank footage going forward for ITAR concerns.. Can't seem to find my source but it feels like it's been a long time since we saw the inside of the tanks.

Their turn around time is super fast. I can't imagine this happening even with NASA. Here's a lot of good luck to SpaceX in 2017.

We're all going to Mars, yay!

Wait. actually...

It's almost like the path to Mars can be divided into a series of small achievements -- like some sort of small steps before a giant leap, if you will.

Does anyone else feel like the COPV problem was not truly solved? This is the second mission loss caused by the same exploding COPV's.

They need to be redesigned and SpaceX is twiddling around the issue to avoid the r&d cost. If I was NASA I would be very hesitant to use their rockets for people at this point

The first COPV did not explode, the pipes leading to it were severed when a strut failed, allowing high pressure helium to flow into the tank (which is why it was a much 'slower' event).

That's a pretty specific claim that "they need to be redesigned and SpaceX is twiddling around the issue to avoid the r&d cost." Do you have any evidence to support that?

There's a lot of speculation around the design and a third lightly reported COPV explosion that happened unexpectedly during testing.

The strut failure is what SpaceX reported but it could have also been a COPV explosion.

Two confirmed COPV explosions and a third possible explosion. SpaceX itself mentioned that an improved design will be done in the future because they had to modify their fueling schedule to increase the safety margin in the things.

"The strut failure is what SpaceX reported but it could have also been a COPV explosion."

It also could have been a sandwich left in the LOX tank, or malware planted by Nigerian scammers. If you don't accept the information provided by the relevant parties then the possibilities are basically unlimited. That's not to say that you must accept what they say, but if you don't then why would you focus on this particular possibility out of millions?

Damn. That's where I left my Sandwich. Do you think it might have survived the explosion?

There's always a chance. You should get in touch with SpaceX and see.

I did. The it was intact after the explosion, but the sniper shot it in flight.

Sounds like a coverup to me. I bet Elon ate your sandwich.

'Unexpected' failures during testing is why testing is done...

The strut failure is consistent with the data, and the accepted conclusion of the report.

They are modifying their procedure because their prop loading procedure was _very_ aggressive (pumping liquid helium into the COPV and allowing it vaporize, absorbing more heat from the environment, resulting in the formation of solid oxygen). They exceeded the tolerances of the COPV, and paid for it. In the future their designs will account for the lower temperatures. Until then, switching to the more conservative prop loading method addresses the issue.

In short yes. I had that same thought too. But I also know that there is a lot that I don't know. SpaceX has done some incredible engineering and what they're doing is hard and unforgiving. Another great aerospace engineer - Burt Rutan - complained a while back that as long as people aren't dying we're not pushing hard enough. To some degree I think he was right. Let's just be happy that SpaceX IS pushing hard and has learned these tough lessons without harming any people so far.

Clearly NASA & FAA know a lot more than you and most of us do. If they choose to let SpaceX continue launching their rockets, there must be a good reason behind it.

True it'd be rather nice to not have to read another article like: http://www.npr.org/sections/thetwo-way/2016/02/25/466555217/...

in 30 years

Unlike the Shuttle, SpaceX's manned vehicle will have the ability to escape an exploding launcher. It's best avoided, obviously, but a repeat of Challenger should end with everybody safe and sound, just not in orbit.

Dragon 2 will have abort modes throughout the flight. The Interplanetary Transport System (aka MCT)? Nope.

Not quite true. The MCT should be able to escape as well, it will just not be able to do it as reactivly as the Dragon 2.

Definitely not as reactively, not convinced it will work as an abort, and not at all on Mars.


Because rockets explode all the time and it's not really dangerous unless people are involved. Rockets are routinely exploded on purpose during testing.

The first loss was due to a strut that failed at about one fifth of the load it was rated for. Nothing to do with the COPV other than that the strut happened to be attached to one.

Your second paragraph is awfully definitive coming from someone who doesn't seem to know what actually happened.

Just because a few rockets explode doesn't mean the whole program is doomed or wrong.

Many rockets exploded before the Russians or Americans got their first astronauts into space, and others exploded even afterwards. That doesn't mean those designs were failures.


A redesign is in the works. They are confident that the change in fueling procedure will prevent the conditions which lead to the failure. They just don't want to ground for a year waiting for a new version when they are confident they can make the current one work.

I think the first part of your comment is a valid concern. SpaceX brought the COPV manufacture in-house, and it's a famously difficult and complex domain in and of itself. I don't see SpaceX twiddling their thumbs to avoid costs, but I do fear that any issues may be intractable and very difficult to address.

Note that SpaceX also brought turbopump manufacture in-house -- and turbopumps are extremely difficult to build. So if you want a list of things to fear, there's another one for it.

The turbo's haven't been the proximal cause of any failures that we know of, to me that's a big difference.

Mission loss?

I think they're referring to the incident that caused this RTF to be necessary, but yes, confusing.

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