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Droneship videofeed, as usual, dropped when the main core had approached, so core landing is not yet confirmed; payload — a Tesla car — is in the planned transfer orbit to Mars, and the two side boosters have landed.


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    This is just off-topic pandering but I’ll allow it ;)

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      I hadn’t watched a SpaceX launch previously. Seeing those two side boosters return to land and touch down together was pretty amazing.

      So the first person to Mars get a free Tesla?

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        Wikipedia says they put it into a Mars transfer orbit with no mention of putting it into orbit around (or just plain into) Mars, so it will be a very large solar orbit.

        And it looks like the center core crashed into the drone ship and they’re keeping mum for a better first wave of PR.

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          I did miss the restored video feed with the smoke clearing and no rocket, as visible in the background of the post-lanuch talk. I was wrong. Technically, it didn’t crash into the droneship.

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            To the best of my knowledge, SpaceX has given up on having a video link from the droneship survive the approach of the core trying to land. Live video of droneship landings has been previously streamed from a helicopter, but that was still closer to shore than this time. The video feed from the ship itself goes down 100% of the time.

            What we see in the last frames is consistent both with a core crash and with a nominal landing, so I am not sure if anyone already knows the fate of the main core for sure…

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              Musk confirmed that the core crashed.

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                Yes, thank you.

                A few quotes from the statements for the press: http://spacenews.com/spacex-successfully-launches-falcon-heavy/

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            Despite SpaceX marketing, it’s heading for a solar orbit.

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              UPDATE: That information was from 30 minutes or so before launch. Things changed.

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                And now it has been confirmed that the orbit crosses the Mars orbit and then goes almost to the inner part of the asteroid belt.

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                  You’d think the exact orbit would have been calculated beforehand…

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                    Actually in this case I wouldn’t be surprised if they didn’t know the exact orbit before the last burn. If second stage has any difference from the Falcon 9 second stage, SpaceX cares about detailed performance data more than about the orbit — so it makes sense to make the maximum possible last burn for the second stage instead of trying to ensure a specific orbit (which usually requires performing slightly below the maximum — just in case).

                    In a sense, the fact that the launch date got delayed multiple times in small increments means that they couldn’t know the exact orbit relative to Mars. Of course, Mars makes a catchy headline, so that’s how the press releases were worded. Now Elon Musk just says «exceeded Mars orbit».

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                      That makes total sense, thanks for the detailed clarification. I forgot this was supposed to be a “test flight”, not an actual mission to deliver a payload to a specific space-time coordinate!

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                        In a sense, there is a wide range of level of significance of the orbit for realistic space missions. We see Falcon Heavy test flight, where you want the things to sound nice and in reality you are collecting the data about the vehicle, not about anything in space. There are missions towards some planet where getting to the planet is what counts. There are solar measurements, where the probe needs to be close to Sun — at some point in time, from some side, but the distance and velocity matter most… but then these are done by gravitational slingshots, and that means that the trajectory must be synchronised very well with the orbital motion of multiple planets, and your launch window is quite tight and doesn’t repeat often.

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              Eventually we will stop investing in chemical rocketry and do something really interesting in space travel. We need a paradigm shift in space travel and chemical rockets are a dead end.

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                I can’t see any non-scifi future in which we give up on chemical rocketry. Chemical rocketry is really the only means we have of putting anything from the Earth’s surface into Low Earth Orbit, because the absolute thrust to do that must be very high compared what you’re presumably alluding to (electric propulsion, lasers, sails) that only work once in space, where you can do useful propulsion orthogonally to the local gravity gradient (or just with weak gravity). But getting to LEO is still among the hardest bits of any space mission, and getting to LEO gets you halfwhere to anywhere in the universe, as Heinlein said.

                Beyond trying reuse the first stage of a conventional rocket, as SpaceX are doing, there are some other very interesting chemical technologies that could greatly ease space access, such as the SABRE engine being developed for the Skylon spaceplane. The only other way I know of that’s not scifi (e.g. space elevators) are nuclear rockets, in which a working fluid (like Hydrogen) is heated by a fissiling core and accelerated out of a nozzle. The performance is much higher than chemical propulsion but the appetite to build and fly such machines is understandably very low, because of the risk of explosions on ascent or breakup on reentry spreading a great deal of radioactive material in the high atmosphere over a very large area.

                But in summary, I don’t really agree with, or more charitably thing I’ve understood your point, and would be interested to hear what you actually meant.

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                  I remember being wowed by Project Orion as a kid.

                  Maybe Sagan had a thing for it? The idea in that case was to re-use fissile material (after making it as “clean” as possible to detonate) for peaceful purposes instead of for military aggression.

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                    Atomic pulse propulsion (ie Orion) can theoretically reach .1c, so that’s the nearest star in 40 years. If we can find a source of fissile material in solar system (that doesn’t have to be launched from earth) and refined, interstellar travel could really happen.

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                      The moon is a candidate for fissile material: https://www.space.com/6904-uranium-moon.html

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                    Problem with relying a private company funded by public money like SpaceX is that they won’t be risk takers, they will squeeze every last drop out of existing technology. We won’t know what reasonable alternatives could exist because we are not investing in researching them.

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                      I don’t think it’s fair to say SpaceX won’t be risk takers, considering this is a company who has almost failed financially pursuing their visions, and has very ambitious goals for the next few years (which I should mention, require tech development/innovation and are risky).

                      Throwing money at research doesn’t magically create new tech, intelligent minds do. Most of our revolutionary advances in tech have been brainstormed without public nor private funding. One or more people have had a bright idea and pursed it. This isn’t something people can just do on command. It’s also important to also consider that people fail to bring their ideas to fruition but have paved the path for future development for others.

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                        I would say that they will squeeze everything out of existing approaches, «existing technology» sounds a bit too narrow. And unfortunately, improving the technology by combining well-established approaches is the stage that cannot be too cheap because they do need to build and break fulll-scale vehicles.

                        I think that the alternative approaches for getting from inside atmosphere into orbit will include new things developed without any plans to use them in space.

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                      What physical effects would be used?

                      I think that relying on some new physics, or contiguous objects of a few thousand kilometers in size above 1km from the ground are not just a paradigm shift; anything like that would be nice, but doesn’t make what there currently is a disappointment.

                      The problem is that we want to go from «immobile inside atmosphere» to «very fast above atmosphere». By continuity, this needs to pass either through «quite fast in the rareified upper atmosphere» or through «quite slow above the atmosphere».

                      I am not sure there is a currently known effect that would allow to hover above the atmosphere without orbital speed.

                      As for accelerating through the atmosphere — and I guess chemical air-breathing jet engines don’t count as a move away from chemical rockets — you either need to accelerate the gas around you, or need to carry reaction mass.

                      In the first case as you need to overcome the drag, you need some of the air you push back to fly back relative to Earth. So you need to accelerate some amount of gas to multiple kilometers per second; I am not sure there are any promising ideas for hypersonic propellers, especially for rareified atmosphere. I guess once you reach ionosphere, something large and electromagnetic could work, but there is a gap between the height where anything aerodynamic has flown (actually, a JAXA aerostat, maybe «aerodynamic» is a wrong term), and the height where ionisation starts rising. So it could be feasible or infeasible, and maybe a new idea would have to be developed first for some kind of in-atmosphere transportation.

                      And if you carry you reaction mass with you, you then need to eject it fast. Presumably, you would want to make it gaseous and heat up. And you want to have high throughput. I think that even if you assume you have a lot of electrical energy, splitting watter into hydrogen and oxygen, liquefying these, then burning them in-flight is actually pretty efficient. But then the vehicle itself will be a chemical rocket anyway, and will use the chemical rocket engineering as practiced today. Modern methods of isolating nuclear fission from the atmosphere via double heat exchange reduce throughput. Maybe some kind nuclear fusion with electomagnetic redirection of the heated plasma could work, maybe it could even be more efficient than running a reactor on the ground to split water, but nobody knows yet what is the scale required to run energy-positive nuclear fusion.

                      All in all, I agree there are directions that could maybe become a better idea for starting from Earth than chemical rockets, but I think there are many scenarios where the current development path of chemical rockets will be more efficient to reuse and continue.

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                        What do you mean by “chemical rockets are a dead end”? In order to escape planetary orbits, there really aren’t many options. However, for intersteller travel, ion drives and solar sails have already been tested and deployed and they have strengths and weaknesses. So there are multiple use cases here depending on the option.

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                          Yeah right after we upload our consciousness to a planetary fungal neural network.