Well done SpaceX

[hamster_nz]

We salute you!

https://pbs.twimg.com/tweet_video/CWyzGUKUkAAzwk0.mp4

[CatalinaWOW]

Third times a charm.  Keep it up!

[Thorondor]

Ever since the Curiosity landing, I never miss a chance to watch a live stream of a space mission . There's nothing quite like it.

[jwm_]

There is this good quote about the difficulty of predicting the future i think is due to Asimov, but i can't find the exact wording. It goes something like..

Science Fiction authors have predicted we would eventually go to the moon for centuries, yet no one predicted the average person would be able to watch it live from their living room as it happens.

[ajb]

Unfortunately missed the live stream, but just watched the recording, and amidst all the cheering there's distinct and well-deserved "holy shit we did it!" 

[calexanian]

+1 Well done.

[boz]

Well done guys...

Proudly wearing my SpaceX hoodie to see star wars this evening (even though its mid-summer here!)

[jh15]

When first seeing Star Wars when first shown, I wondered if they were on a budget and dug up dusty props such as ww2 bomber parts.  Also wondered why the hologram projection was a snowy 50 lines or so.

The hairdo, well, never know what to expect from other gender anyway.

Glad Star Trek was more science fiction than space opera.

Anyway tonight was best feeling I got since the Mercury missions.

Had to hold my wife's head up from book she was reading, guess not as exciting to some.

The landed stage looked very uninteresting I'm sure to many news watchers, too bad they didn't have fireworks display come out the top after.

[HP-ILnerd]

Epic!
What a moment!

[free_electron]

The Force is strong with this one ...

[bookaboo]

Very impressive indeed 

[Howardlong]

Ever since the Curiosity landing, I never miss a chance to watch a live stream of a space mission . There's nothing quite like it.

I can assure you the exhilaration is even better when it's some of your own handiwork that's on board.

[Tomorokoshi]

The landed stage looked very uninteresting I'm sure to many news watchers, too bad they didn't have fireworks display come out the top after.

They should have landed on the wrong landing pad. Then they could compete with Miss Universe.

[Tomorokoshi]

There is this good quote about the difficulty of predicting the future i think is due to Asimov, but i can't find the exact wording. It goes something like..

Science Fiction authors have predicted we would eventually go to the moon for centuries, yet no one predicted the average person would be able to watch it live from their living room as it happens.

It seems most everyone missed the development of the smart phone. There are too many plots that would be totally negated by possessing a small computer with instant access to knowledge, can run any number of programs, allows communication using several methods, etc. Perhaps it will cause more realistic situations. I can see where science fiction already looks dated when situations arise where problems could have been easily solved with one.

[ajb]

There is this good quote about the difficulty of predicting the future i think is due to Asimov, but i can't find the exact wording. It goes something like..

Science Fiction authors have predicted we would eventually go to the moon for centuries, yet no one predicted the average person would be able to watch it live from their living room as it happens.

It seems most everyone missed the development of the smart phone. There are too many plots that would be totally negated by possessing a small computer with instant access to knowledge, can run any number of programs, allows communication using several methods, etc. Perhaps it will cause more realistic situations. I can see where science fiction already looks dated when situations arise where problems could have been easily solved with one.

That's one interesting thing about The Expanse--a big chunk of the day-to-day technology in that world is the clear evolutionary offspring of today's smartphones and tablets, and the connectedness of that technology is thoroughly woven into the plot.  The books are basically classic near-future space opera but extrapolated from the technology and politics of today rather than those of decades ago, so if you're into that genre if highly recommend the series.

(The series also covers the colonization of Mars, so it's not off topic here, right?    )

[HP-ILnerd]

Some slick new footage from the launch/landing.

Man, this is cool.   

 

[dannyf]

I have a difficult time understanding the real impact of this. Seems more of a gimmick.

[HP-ILnerd]

I have a difficult time understanding the real impact of this. Seems more of a gimmick.

80% of the cost of the mission is the bit they just landed, 0.3% is the propellant cost.  Reusing said bit amortizes the cost linearly with the number of reuses (+ refurb cost).  FYI, recent inspection of this vehicle revealed no damage.

Think of single-use jumbo jets as an analogy to expendable rockets.

The Holy Grail, of course, is fully reusable single-stage-to-orbit (SSTO).  This isn't that, but it's a massive step in that direction.

[jwm_]

The Holy Grail, of course, is fully reusable single-stage-to-orbit (SSTO).  This isn't that, but it's a massive step in that direction.

Is their any practical use of solid state rocket fuel in civil applications?

I know it is crucial in military applications since you do not want to own an ICBM that requires half a day to refuel (and being a huge explosive target) before launching.

Also, solid fuels are usually refined chemical products, while liquid fuels are simple crude products, hence much cheaper.

The big issue with solid fuels is you cannot throttle. Once ignited, they keep burning with whatever profile you designed them with for the most part.

    John

[ajb]

The Holy Grail, of course, is fully reusable single-stage-to-orbit (SSTO).  This isn't that, but it's a massive step in that direction.

Is their any practical use of solid state rocket fuel in civil applications?

I know it is crucial in military applications since you do not want to own an ICBM that requires half a day to refuel (and being a huge explosive target) before launching.

Also, solid fuels are usually refined chemical products, while liquid fuels are simple crude products, hence much cheaper.

The big issue with solid fuels is you cannot throttle. Once ignited, they keep burning with whatever profile you designed them with for the most part.

    John

Yep, which complicates a lot of launch abort scenarios, especially on a crewed launch.  One of the many neat things that SpaceX does is conduct a static engine test of every vehicle on the pad before launch, once a couple of days before the launch, and again between ignition and lift-off--they can verify the performance of the engines and if necessary abort the launch at literally the last second before the launch.  Can't do that with solid fuel.  You also can't re-light a solid fuel stage and use the existing engines to do a soft landing.  There might be options to do that with a hybrid fuel system, but I'm not a rocket scientist. . .

[dannyf]

I am sure someone somewhere did an analysis.

80% of the cost of the mission is the bit they just landed, 0.3% is the propellant cost. 

For everyone on the launching pad, the cost is about 1/3 the rocket, 1/3 the payload, and 1/3 insurance. Figure from early 1990s.

Reusing said bit amortizes the cost linearly with the number of reuses (+ refurb cost). 

A little bit more complicated. How much MORE did it cost to design and manufacture reusable rockets vs. single-use ones? The fuel needed to land the rocket, plus safety margins, were essentially part of the payload at launch time. So to lunch the same payload, you will need more fuel / rocket structural elements than you would if a single-use rockets were used. ....

I suspect that something like this is good, at best, for LEO launches. For high-orbit launch like geo-stationary birds, the efficiency just isn't there.

FYI, recent inspection of this vehicle revealed no damage.

How many times could it be reused? What repairs would need to be made before it can be reused? Is there any performance hit (like probability of failure) from reusing the rockets? ...

Without seeing the analysis, it looks to be a marketing stunt to me.

[dannyf]

Is their any practical use of solid state rocket fuel in civil applications?

Home deliveries of your take-out orders from Amazon?

safety is one concern, cost another, both financial and environmental.

One I have thought about is automotive accident avoidance; or driver escape mechanism.

[dannyf]

Then Russian kids will be playing with ejection rockets instead of air bags.

That's the least of your concerns: think about what a bunch of those can do, creatively.

[dannyf]

I suspect that the whole reusable rocket thing is less about lowering costs for commercial launches but more about getting potential military contracts / applications.

For Musk to be able to reland a rocket (from orbit), he must have been able to control thrust (just trust, not thrust vectoring), potentially reignitable rockets.

Reignitable rocket engines would allow satellites to be repositioned while in orbit, making them difficult to be destroyed by anti-satellite missiles. It would also make possible in-orbit / standby missiles that can greatly reduce the time for them to be deployed, making them less likely to be intercepted. Or it could be mounted on re-entry vehicles, ...

[Brumby]

I suspect that the whole reusable rocket thing is less about lowering costs for commercial launches but more about getting potential military contracts / applications.

I don't see why the distinction.  The cost of getting a payload into orbit is based on it's weight, not it's purpose ... and if SpaceX do start doing launches for military customers, you can bet your boots it will be for commercial reasons.

For Musk to be able to reland a rocket (from orbit), he must have been able to control thrust (just trust, not thrust vectoring), potentially reignitable rockets.

I don't see why you would exclude thrust vectoring.  I'm no rocket scientist, but that would seem to be kinda critical, especially for re-landing.

Reignitable rocket engines would allow satellites to be repositioned while in orbit, making them difficult to be destroyed by anti-satellite missiles. It would also make possible in-orbit / standby missiles that can greatly reduce the time for them to be deployed, making them less likely to be intercepted. Or it could be mounted on re-entry vehicles, ...

Repositioning satellites in orbit is not likely to make much difference as a target for an anti-satellite missile.  The tracking on such a missile has to chase down something travelling at over 17,000 mph, so a change in position that could be afforded by on board rockets isn't a big challenge.  As for missiles parked in orbit (if that's what you are saying) - I think they would be rather over-exposed.