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SpaceX Enters a New Stage of Reusability (mashable.com)
SpaceX will now be attempting to land and reuse all of the rockets it launches. Over the weekend, SpaceX launched and successfully landed its second Falcon 9 Block 5 rocket in Cape Canaveral, Florida. An anonymous reader writes: The landing of this vehicle, designed with reusability in mind, marks the beginning of a completely recyclable era of rockets for the company. The Block 5 can be used hundreds of times if recovered successfully. Now that the company has transitioned to this more reusable model, recovery will be an even more crucial part of the launch. In a two week period, it's planning five recoveries. Mashable: The landing marks one of the first landings and launches of the company's newest, upgraded Falcon 9 rockets, called Block 5. Before this launch, SpaceX got rid of a backlog of their Block 4 rockets by launching without landing them back on Earth. That type of launch without landing is the traditional way of getting things to orbit, but SpaceX managed to change that. The whole point in the company's rocket landings hinge on the fact that it could reduce the cost of flying to orbit. By reusing rocket stages for multiple launches, it could drive down the exorbitant cost of flying to space for companies and nations around the world. SpaceX has been killing it the past couple years. The company -- founded by Elon Musk -- launched 18 times in 2017.
No, but they are oil powered. RP-1 aka kerosene.
>> SpaceX has been killing it
Not sure you're old enough to remember deaths involved in space flight, but this may not be the smartest statement for the marketeers to put out.
A funny thing happened on the way to outer space... SpaceX developed a business model that is quickly obsoleting Russia's space launch supremacy. Now that it's an actual threat, expect to see frequent bot attacks on SpaceX, Elon Musk, Tesla, Hyperloops, et cetera. That's how the disinformation age works. Delegitimize anyone that is deemed a threat.
Those Block 4 first stages did land albeit on the bottom of the ocean.
Sig?
This is really impressive. Lower cost access to space helps us all. With this and Tesla, Elon Musk is really hitting it out of the park!
I would love to have an old block4 standing on its landing legs outside a local museum. I hope they save some of them.
I came to the datacenter drunk with a fake ID, don't you want to be just like me?
SpaceX got rid of a backlog of their Block 4 rockets by launching without landing them back on Earth.
Oh they "landed" them. The landings were a little more... exuberant than the Block 5 rockets will be though.
Space elevators are infinitely more dangerous than current systems. If a rocket explodes, the occupants die. If the self-destruct fails, a few people may die wherever the remnants fall. If a space elevator breaks, everybody dies.
No. That idea comes from people who haven't actually thought it out, and the idea of catastrophic space-elevator destruction got popularized by the dramatic but unrealistic space-elevator destruction scenes in Kim Stanley Robinson's Red Mars.
A good way of visualizing what space elevator would be made out of is to picture spider silk, but lighter. A space elevator can't be massive: it has to carry its own weight 40,000 km. If a space elevator breaks, the parts that are high up (and thus have high energy) disintegrate in the atmosphere; the parts that are lower down (and thus don't have much energy) sift down like dandelion fluff.
People have simulated this.
Of course, the material to make a space elevator does not yet exist. But if it did exist, we know it would have to be exceptionally light.
http://www.geoffreylandis.com
IIRC, SpaceX is planning on launching all their Block 4s, especially when the mission requires "Maximum Performance" (which means they can't be recovered). In terms of what they have left, I think it's only one or two - certainly less than five.
They cost $30M or so to build, so if they're flyable, SpaceX wants to make money on them.
myke
Mimetics Inc. Twitter
Daily Kos-- which you can hardly call a pro-billionaire publicity rag-- had an article discussing exactly these points:
https://www.dailykos.com/stories/2018/5/29/1767826/-The-War-on-Tesla-Musk-and-the-Fight-for-the-Future
http://www.geoffreylandis.com
Space flight is very dangerous, and I don't see it becoming much more safe in my lifetime.
SpaceX is making it much more safe in two ways:
1) Coming up with a highly reliable design that has been tested so often failure modes are more rare than aircraft.
2) Designing a proper escape capsule to eject a crew module in the event there is a problem. Which commercial aircraft having nothing like for passengers in case something goes drastically wrong...
In the near future I would rather be on a rocket than a commercial aircraft,.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Space flight is very dangerous, and I don't see it becoming much more safe in my lifetime.
Maybe. It's gotten a lot safer during my lifetime but I was born near the start of the space age when we really didn't know what we were doing. We've learned a lot in the last 5 decades. (at the cost of some lives) That said it's still quite dangerous and likely to remain so for the near future. It's going to take quite a while to get the technology of chemical rockets to the point where they have a safety record even close to airlines at reasonable cost. They have a fairly good safety record today but at outrageous cost. The real question is whether we can keep or improve on the current safety record while reducing the cost to orbit. That is not going to be easy to do and won't happen overnight.
Unless we can get into space without explosive force, such as a space elevator, it is going to be dangerous, and people will die in the future from space travel.
You think a space elevator wouldn't be dangerous? You might want to think about that a little deeper. Those things are enormously dangerous even if they prove to be possible to actually build. Not just to the users of the elevator but potentially to people on the ground or in space if they fail.
Anything dealing with space is going to be dangerous. But it's conceivable it could be made safe to a reasonable degree someday. Won't be easy but it could be made to be reasonably safe for most travelers. Take the airline industry for an example. It took decades but eventually it became quite safe with good regulation and technological advancement. Same with ocean travel. I'd expect the space industry to take longer (harder problem) but I also could someday see spaceflight being "routine" to a reasonable degree.
Average lifetime for a mammalian species is 1 million years. A few mammalian species last as long as 10 million years.
About 300 million years from now the brightening of the sun will indeed mean "we" will have to do something, but the term "we" in that phrase means "some different future species that is related to us about as closely as we are related to the very first reptiloids that would, in the future, evolve into dinosaurs."
http://www.geoffreylandis.com
We should get off oil and use nuclear!
Is fuel cheap enough for us to do this now?
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We should get off oil and use nuclear!
No, no, the only serious nuclear powered rocket is Project Orion.
Yes, yes he will.
Minute Physics explanation: https://www.youtube.com/watch?...
Venus would be a great destination for nuclear thermal, and an excuse to develop the tech to a point that people could be more comfortable with using it on Earth. You still have to launch nuclear fuel from Earth, of course, but just as a payload, not in the form of a operating, short-lived-isotope-generating reactor. People could rest easy knowing that the only time it would be turned on would be in the atmosphere / orbit of an entirely different planet. Of course, once you've had such a rocket working on another planet for years without incident, the question would arise... why not Earth?
It would be exceedingly useful as an ascent vehicle for a Landis-style (floating, breathable-air-lofted) Venus habitat. While the need for using a light gas as propellant makes pure hydrogen the only realistic option for nuclear thermal, and hydrogen is in relatively limited supply in Venus's atmosphere, the extreme fuel efficiency of nuclear thermal rockets (and in particular the airbreathing hybrid variants) means that you just don't need that much of it - less than all but the most hydrogen-sparing of chemical propellant options (such the hydrogen-free LOX-CO or LOX-C2N2 combinations... although even they're best with a bit of methane or H2 in the mix). It also means that the ascent stage can be vastly lighter when fully fueled, allowing for far more human/water/crop mass inside a given habitat rather than dedicating ~90% of the habitat's lift to lofting a fueled ascent stage. Lastly, some nuclear thermal designs involve compressors and can effectively hover indefinitely - eliminating the need*** for returning stages to be balloon-lofted during docking to the habitat's underside.
You certainly can also use a nuclear thermal rocket on Mars as well - not just Venus - but it's not nearly so essential. It's a lot easier to get off of Mars' surface with chemical rockets than it is out of Venus's atmosphere - even directly landing your Earth-Mars transfer stage (as in the case of BFR). With Venus, realistically you need at least two stages for a chemical-powered ascent vehicle, and the payload fraction is low. And you have to re-mate the stages - each docked individually - while they're hanging from the underside of the habitat.
*** It's technically possible to have a SpaceX-style platform landing, but extremely difficult. If the platform is on the top of the habitat, the platform has to be able to hold an extremely heavy rocket (large chunk of the total habitat's mass) without flipping it over. If the platform is hanging from the bottom, you need a lot of clearance - and in either regard, a huge amount of structural strength on the platform, yet with strict mass limits. The failure modes on this sort of landing/docking are also a lot more severe than with balloons (which reenter further away from the habitat). You have as much "go-around" time as you want with a balloon, and are never going to accidentally send a returning stage crashing through the habitat at hundreds of meters per second; you just have the habitat approach from well above and use a tethered drone to mate the two together. Balloon-lofted returning stages have been investigated before for use on Earth (and ballutes have been used for deceleration of returning spacecraft), but never implemented.
"Lock and load, Brides of Christ!"
To be honest, my comment was made in jest.
You really make me wish that the energy put toward Mars was focused on Venus.
I demand floating cities on Venus. Not because of some Star Wars reference but to stick it to those mole-like Martians!
To be honest, my comment was made in jest.
To be honest, my comment was made in jest as an attempt to top your jest.
We should get off oil and use nuclear!
Once we’re out of the atmosphere. .
It's jest all the way down.
Jest stop it.
I would but I jest couldn't help myself.
Normal Earth air. Both nitrogen and oxygen are lifting gases on Venus.
That would be a prototyping step, yes. Just like Mars habitats are also first tested on Earth. On Earth, however, you'd have to use heliox as the lifting gas.
Actually 1) we don't know whether there's any sulfuric acid rains, snows or frosts in Venus's middle cloud layer, and B) it would actually be preferable if they were there!
There's no shortage of polymers that can withstand sulfuric acid well (particularly, although not exclusively, fluoropolymers). Sulfuric acid, however, is a huge resource on Venus. It's the primary available source of hydrogen, and extremely easy to decompose into useful resources. Simple heating first off drives off free water. Further heating decomposes H2SO4 into SO3 and more H2O. Further heating of SO3 over a vanadium catalyst yields SO2 + O2. Contrarily, the SO3 can be used as a conditioning agent in the scrubber for nucleating more H2SO4 and capturing free H2O.
The main disadvantage of sulfuric acid in Venus's middle cloud layer is that there just isn't that much of it! It's more like a bad smog (or more accurately, vog). Visibility can be several kilometers, it's that sparse. You have to process a lot of air to get the hydrogen you need for ascent vehicle propellant.
Like this.
"Lock and load, Brides of Christ!"
Infinite jest.
The NASA claim (not YOUR claim - I am not calling YOU dishonest) that the Soyuz is "man-rated" is and always has been a fraud, just as it was for the Shuttle. Neither vehicle would pass the "man rated" standards being required for SpaceX's Falcon+Dragon or Boeing's Atlas+Starliner.
NASA Had no supervision over the design and construction of Soyuz and no ability to dictate ANYTHING about the system nor does NASA have any control over the system as it is in use. NASA has no supervision over production or testing of the Soyuz system. The "man rating" of Soyuz by NASA is a combination of diplomatic nicety (it would be bad internationally to claim the system was unsafe or not up to our standards) and necessity (it's the only way to get to ISS right now and saying its not man rated would present a dilemma).
Remember: NASA had NEVER flown a shuttle unmanned before stuffing humans into it and firing it into orbit. The system had NO survivable abort mode during the 1st ~2 minutes of flight and it was not automated sufficiently to fly itself so it could not be flown unmanned. John Young and Robert Crippen should go down in history as the bravest pair of test pilots in world history, and given the capabilities of modern computers, nobody should ever need to do that again. Even the gliding approach-and-landing tests done on Enterprise years before the 1st orbital flight were never done without humans aboard. NASA has never previously enforced the current supposedly rigidly-enforced REQUIRED "man rating" standards onto any of its prior vehicles nor the Russian systems it rents rides on. It's very much like the anti-SpaceX rules that the Air Force had when SpaceX first started trying to get certified for launches. The Air Force had simply supposed all their prior established vendors were "certified" and when SpaceX wanted to get certified, the USAF had to start making the rules (which the big defense contractors had input into and were not required to pass).
SpaceX cargo dragons have spend more time on-orbit already than ALL of NASA's previous capsules (Mercury, Gemini and Apollo) COMBINED. Those cargo dragons have also flown more launches and reentries.
They have done some work on their site since last I saw (probably the last time Venus was mentioned as a more suitable destination than Mars and the inevitable 'floating in a dense atmosphere is impossible!'). It's nice to see them still doing good work.
Cheers.
If the real WindBourne had modpoints I'd know about it ;)
The same thing that will reduce cost to orbit will be the biggest boon to safety: launching more frequently.
That's certainly going to be a big part of it. Kind of a chicken and egg problem though. To launch more frequently you need to reduce costs and to reduce costs you need to launch more frequently. This is a perfect example of where subsidies can make a ton of sense.
Although bear in mind that launching more frequently will come with a body count. Some of the lesson we are going to learn about how to do space travel safely are going to be learned at the cost of some lives and we're going to have to be ok with that in the big picture. There is a saying in the maritime industry that "the rules were written with blood" and the space industry will not be any different.
It's very hard to work out all the bugs of a rocket that only launches a dozen times before it's replaced by a new model, compared to a rocket that launches thousands of times a year.
Definitely true. Of course you don't want to build a thousand rockets and find out after the fact that you screwed up the design either. Basically it's going to take a long time to ramp up to significant volume if we do it right. Decades to centuries if we're being realistic given the economic incentives (or lack thereof) no matter what Elon Musk claims. We didn't go straight from the boats that Columbus sailed across the Atlantic to modern ocean liners. That took literally centuries of technological advancement. No real reason to believe that development of technology to travel in space will happen in a compressed time span either. It's a hard problem and an expensive one too.
Dont want that stuff falling back on us as a comet :(
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