SpaceX Dragon Returns Home From ISS (floridatoday.com) 55
An anonymous reader quotes a report from Florida Today: A SpaceX Dragon capsule that helped prepare the International Space Station for future commercial astronaut flights has returned to Earth after a stay of more than month-long mission. A robotic arm released the unmanned capsule packed with 3,000 pounds of cargo at 6:11 a.m. EDT, then fired thrusters several times to move a safe distance away from the station orbiting about 250 miles up. The departure began a less than six-hour journey that culminated in a Pacific Ocean splashdown at 11:47 a.m. EDT, about 300 miles southwest of Baja, California. The Dragon launched from Cape Canaveral early July 18 on a Falcon 9 rocket and berthed at the station two days later. Among the cargo brought back from space Friday were a dozen mice from a Japanese science experiment -- the first brought home alive in a Dragon. Samples from mice euthanized as part of an experiment by pharmaceutical company Eli Lilly also were on board. Results were returned from an experiment that studied the behavior of heart cells in microgravity, and from research into the composition of microbes in the human digestive system, NASA said. Findings from both could help keep astronauts healthy during deep space exploration missions. SpaceX plans to launch a Falcon 9 rocket from Cape Canaveral Air Force Station next Saturday, Sept. 3.
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This is so much more important because instead of the usual military contractors building the capsule, an internet sensation military contractor is building the capsule, and it only took him 60 years to catch up.
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"and it only took him 60 years to catch up"
Given that he's only 45 and SpaceX is only 14, that's some kind of magic
Re: Sixty Years Ago... (Score:2)
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Well, it beats making them into the world's most complicated airplanes as with the space shuttle. SpaceX has proven that they can do vertical landings of the first stage intact onto both land and a seagoing barge; after a trip out of the atmosphere and to about 1/5 of orbital velocity but not into orbit. They plan to do a parachute-less vertical landing of the Dragon capsule after a heat-shield re-entry. That turns out to be far less expensive and complicated than a space plane. It does turn out we need a l
Re: Sixty Years Ago... (Score:2)
It does turn out we need a lifting body for much larger vehicles.
Not if they're equipped with powerful-enough retros... ;)
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Well, it beats making them into the world's most complicated air planes as with the space shuttle. SpaceX has proven that they can do vertical landings of the first stage intact onto both land and a seagoing barge; after a trip out of the atmosphere and to about 1/5 of orbital velocity but not into orbit.
It's great to see the myths of non-reusable first stage technology being dispelled.
That turns out to be far less expensive and complicated than a space plane. It does turn out we need a lifting body for much larger vehicles. It still doesn't have to be a plane, though.
I think you have to separate the concept from the implementation of a space plane design. SpaceX's launcher effort is less expensive and complicated than the space planes implemented so far. However both Buran and the Space Shuttle had the orbiter on the side of the stack where their heat shield was exposed to debris from the launch vehicle. So much so it was considered to be 'In-Family' because it would occur every launch to
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It's great to see the myths of non-reusable first stage technology being dispelled.
Indeed, SpaceX has thoroughly demolished the claims of SSTO fans that reuse and low cost are somehow incompatible with staging. With an aluminum-bodied, pure-rocket launch system using simple kerosene-burning rocket engines, SpaceX has accomplished the bulk of what Skylon promises to one day achieve with its supertech air-breathing engines, liquid hydrogen fuel, eggshell-thin ceramic heat shielding, etc.
We don't need wings.
They are useful though.
For what? Air breathing launchers need them because of their weaker engines, but staged launchers don't n
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I'd argue they need to prove that the vehicle weight is lower completely dry (and even that's biased in favor of airbreathing winged vehicles because it ignores the extra complexity and higher cost materials). It's the dry structure that's the expensive part to build and operate, you need the reduction in LOX tank size to make the vehicle smaller and cheaper after adding the wings, air breathing engines, landing gear, etc. If you can make the vehicle cheaper at the cost of pouring in a bit more propellant b
Re: Sixty Years Ago... (Score:2)
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We could also use risk management metrics to make the case against spaceplanes. The shuttle had too many criticality 1 components, etc.
The Shuttle had those critical components because it was a complex vehicle with launch components on it. If you are using the risk management metrics of a side by side launch configuration with engines in it, then we are not talking about the same thing.
The CAIB report pointed out that it's risk analysis of the shuttle launch configuration produced approximately 130 impacts to the heat shield per launch. That would be eliminated in a top of stack configuration. So too would the main engines making for a le
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Boeing? I don't understand your point about Boeing.
That they would have considerable experience to bring to optimizing such a space glider (x-37b) and that they selected that design to demonstrate the technology.
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And they left it to Sierra Nevada to propose a space plane.
Indeed and you have supplied good examples of the craft with Dream Chaser, which is a more optimized design - thanks. I accept your's and cjameshuff's points about a space plane. I'm not arguing a capsule vs plane approach, simply commenting on the state of art in that technology. If a market emerges perhaps we will see more of them.
Yes, but their candidate for Commercial Crew is the CST-100. Which looks like a modernization and upscaling of the Apollo CM.
I have nothing against the capsule approach and have often lamented on how progressed space travel might have been had the Apollo platform been developed more. Far from arguing
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Falcon 9 isn't Al. It's Al-Li with a composite interstage. It also has a lower dry mass than iso-grid designs like the EELVs.
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Al-Li is ~95% Al. Nobody lists all the components of an alloy every time they refer to the primary material. And the interstage is a tiny fraction of the structure, which originally only served to connect the stages and house separation hardware. It's not at all comparable to Skylon's composite LH2 tanks and airframe.
They've done a good job of optimizing it, but that doesn't change the fact that they chose stir-welded aluminum because it was relatively cheap and easy compared to higher performing alternativ
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Well if you remember the X-33 debacle, or the Boeing 787 debacle, composites aren't always the best idea. It's a lot easier to repair Al-Li than composites which is important for a reusable vehicle. Also AFAIK you need a large oven to cure the composites or an autoclave. I wouldn't be surprised if it took a lot longer to manufacture a composite structure which has an impact on production capacity and cost per unit. Al-Li might seem trivial now but a couple of decades back when NASA was doing the DC-XA they
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That said, the point of a SSTO with airbreathing is not the *cost* of the fuel, but the weight-reduction itself, since the added weight that has been avoided in this way can be used for payload.
Even Elon Musk said it's not about the cost of the fuel, but the fact it impacts the useful weight of the payload. ;-)
It's possible, thus, that for LEO an airbreathing spaceplane is more suited than a rocket, especially if that rocket isn't fully SSTO. You say it doesn't save 'much', but the oxidiser on a typical roc
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Did you miss the part about Skylon having double the dry mass of the Falcon 9?
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Is Skylon the only possible system using atmospheric air?
People seem to be a bit too much focussed on Skylon, although I admit I'm interested in it too, from a technical/technological standpoint.
The *principle* of the matter I just explained stands, though: that which you avoid taking with you as weight (the oxidiser) means you do not have to carry that weight, plus, you don't need to carry the weight of the fuel needed to carry the weight of the oxidiser, plus you do not need the weight of the fuel to lift
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It's great to see the myths of non-reusable first stage technology being dispelled.
Indeed, SpaceX has thoroughly demolished the claims of SSTO fans that reuse and low cost are somehow incompatible with staging.
We agree that this is a step forwards in getting to orbit.
We don't need wings.
They are useful though.
For what?
For operating a vehicle in atmosphere, which occurs at two critical stages of a spacecraft's mission.
Spaceplanes are dead.
Does a spaceplane have to include engines?
Take Skylon as a representative example:
No. That is specifically the design I am arguing against. Please check my post again and you will see I deliberately *exclude* the mass of the engines.
Perhaps it would make more sense if I introduced the term "Space Glider" to describe what I am talking about.
assuming it lived up to expectations, Skylon
I agree, I doubt this design would have lived up
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For what?
For operating a vehicle in atmosphere, which occurs at two critical stages of a spacecraft's mission.
That doesn't answer the question. Spacecraft spend only a tiny fraction of their lives in the atmosphere, and sustained aerodynamic flight is not a requirement during their short passages through it during launch and landing. So what do they need wings for?
No. That is specifically the design I am arguing against. Please check my post again and you will see I deliberately *exclude* the mass of the engines.
Engines using diluted low-pressure gaseous ambient oxygen as an oxidizer have poor thrust to weight ratios, and wings are generally used to make up for that, making it possible for a craft with underpowered engines to accelerate early on, though at a cost
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What do you need wings for?
As I said. What my OP was suggesting was that we have not seen the most optimized design for a space plane, or more specifically, a space glider. We have never implemented a low mass glider from space.
Note: "to operate from an airport" is not an answer.
To reduce ballistic forces on re-entry, to not carry volatiles for landing, to carry more than three tons of payload back to earth, to build a simpler vehicle. Perhaps to use some of the launch energy on delivering a product produced in orbit to a specific place on earth. I don't know what possible future requ
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SpaceX has thoroughly demolished the claims of SSTO fans that reuse and low cost are somehow incompatible with staging. With an aluminum-bodied, pure-rocket launch system using simple kerosene-burning rocket engines, SpaceX has accomplished the bulk of what Skylon promises to one day achieve with its supertech air-breathing engines, liquid hydrogen fuel, eggshell-thin ceramic heat shielding, etc.
Let NASA manage this and I bet they can prove the opposite after a few test flights.
Weirdly specific statement (Score:2)
"Among the cargo brought back from space Friday were a dozen mice from a Japanese science experiment -- the first brought home alive in a Dragon. "
Okay... but what is the significance of this? The article itself doesn't really flesh this out either.
- Have they unsuccessfully tried to bring home live mice before, but they've always ended up dead?
- Have they successfully brought live mice back to earth, but in some other spacecraft?
- Are Dragon flights to the ISS frequent and routine to the point where we're
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The significance of this is Elon Musk, who is the self-driving Uber of dot.com billionaires and is the hero of our times.
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Well, I knew Steve Jobs well enough, and have met a few civilian astronauts and a bunch of other rich people. None of the others seem to have done so much for the long-term future of the human race as Musk has in leading the path to more affordable spaceflight.
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I knew the woman who used to style Joe Pepitone's toupee.
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Re:Weirdly specific statement (Score:5, Informative)
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What will the life support systems do beyond maintaining atmospheric pressure, temperature, and power? CO2 scrubbing?
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What is the limiting factor? Buildup of CO2?
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People need a certain amount of oxygen for their metabolism, you need to carry that much. CO2 effects the blood pH: too little and the body is too alkaline, too much and it's too acidic. So, you need to maintain a precise amount of CO2 and remove the rest. The scrubbers in the space shuttle were able to regenerate the CO2-absorbent material after use, so there was use of power but material wasn't consumed.
Beyond this, you need to control temperature and humidity.
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Just put a warning label on the side:
"Use of this product may be hazardous to your health. This product contains SpaceX, which has been determined to cause death in laboratory animals except if you land in California in which case it causes cancer."
What are we gonna to tonight ? (Score:2)
Just a notice that Pinky and the Brain are back.
https://www.youtube.com/watch?... [youtube.com]
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