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Comment: Re:Falcon Heavy will land 3 boosters per mission (Score 1) 72 72

The video has them all landing together largely for dramatic effect (or to avoid modeling an ASDS). For most real launches, the center core will be much too far downrange and moving too fast to return to the launch site, and will have to land on an ASDS positioned out at sea. The smaller side pads are intended as fallbacks in case the center pad is unreachable or otherwise out of commission. They'll probably use two ASDSs for the center and one side core until they get a second land-based landing site constructed.

Comment: Re:Since they are on the ocean... (Score 3, Informative) 72 72

Rockets are fragile, they can't take much mistreatment. A net would at most catch some debris...they don't want debris, they want a rocket. And in normal operation, they should be able to soft land upright on the platform, so a net would be an unnecessary complication in the best case...in the worst case, the net system gets in the way and causes a landing failure.

Comment: Re:It's all about economics (Score 1) 45 45

It's not clear that the total cost of implementation will be cheaper. Sattelite launches cost $50-250 million each...

LauncherOne is targeting $10 million per launch and would put up 2-3 satellites with each launch...it will be one of the most expensive ways to lift mass to orbit at roughly $44000/kg, and still won't be nearly as bad as you state. The Soyuz launches, with over 30 times the payload capacity, would put up many more satellites at far lower cost per satellite.

So what? That has nothing to do with whether the economics of this are workable or not.

You wouldn't have to ask that question if you'd bothered to read the entire text you were responding to. The rural population is not "by definition" small, it is a substantial fraction of the global population.

Comment: Re:"Acquired" 65 rockets? (Score 1) 45 45

And apparently options for 100 more. 139 flights on a launcher that doesn't exist yet, from a company that has never launched anything.

Look at SpaceX...the Falcon 9 has been extremely successful, but it's not the rocket they started with. Their first launcher, the Falcon 1 had multiple launch failures and was ultimately scrapped along with the planned Falcon 5 in favor of the more efficient and capable Falcon 9. Depending on the Falcon 1 being a massive success when it was still a paper rocket would have been rather foolish.

Comment: Re:Iridium Redux? (Score 2) 45 45

The satellites are cheaper, more capable, and far more numerous, and there's a lot more of a market for low latency internet access that doesn't have to follow fiber links on the ground than there was for the capability to make an occasional call with an expensive, clumsy sat-phone.

And cities cover a tiny fraction of the Earth's surface. Around 20% of the population of the US lives in rural areas, and the fraction is much higher in developing countries. It's also not just people in remote areas that will be interested in this, the low, perdictable latency will be of interest to financial institutions, among others.

Comment: Re:The tapes were re-used (Score 1) 307 307

On top of this, these were tapes of mostly telemetry data, of which most of the interesting data had been copied for whatever it was needed for. That includes the video: it was slow-scan video which had already been converted to more useful forms for live broadcast...we could do a better conversion now if we had the data (especially for the first few minutes, where the scan converter was misconfigured), but they didn't think it was necessary, especially when we brought back reels of film from the Maurer DAC showing the astronauts working on the moon in far greater quality than any video equipment at the time could have managed, not to mention all the still photos, which were far more accessible at the time.

Comment: Re:Offshoring (Score 1) 173 173

It's their fault that the past inadequate funding led to delays, therefore they don't deserve the full amount of funding required to meet their schedule? You're seriously making that argument? Delays resulting from underfunding are not justification for continued underfunding.

And Orion? Orion won't fly until around 2025 at best, will cost several billion to fly if it ever does (just the SLS to launch it will cost about a billion), and won't ever visit the ISS or any other space station...it would be gratuitously wasteful to use it for such a mission.

Comment: Re:4000 (Score 1) 98 98

(Damn, I thought it was 250-ish each way, not round trip.)

It's 250-ish round trip to the satellite and back, but comms satellites aren't very interesting to talk to. It's 250-ish each way to the server and back. Around half a second of delay before you can get a response to a message while working over a geosynchronous satellite link.

Comment: Re:Yeah (Score 1) 100 100

A first stage is not an airplane. Making it land like an airplane entails adding most of an airplane to it...wings, jet engines, unfolding propellers, substantial, steerable landing gear, various covers and other mechanisms that open and close in flight, mechanisms to detach the disposable tanks, etc. This is not making things simpler.

Comment: Re:30% launch cost reduction is huge (Score 1) 100 100

Reusing the engines would be a significant cost reduction, but they're going about it in a particularly complex way, and their level of reuse still falls short of their competition's. By their own statements, they throw away 20% of the economic value of the stage. SpaceX just needs to make the first stage a bit oversized for the second stage. That costs them a somewhat larger vehicle (which is reused for multiple launches, so this cost only has to be paid once) and propellant (which accounts for 1% of a launch).

After 5 launches, Adeline will have cost as much in disposable tanks as an entire new first stage. A Falcon 9R might fly as many as 40 times without major refurbishment.

Comment: Re:And they are off. (Score 2) 100 100

I think you're talking about the Jason-3 launch. That's actually a couple launches away, though it'll be their first landing attempt on the West Coast.

CRS-7 is launching June 26th (bumped back a bit, probably to let them reshuffle things to account for cargo that was supposed to be delivered on the last Progress) from Cape Canaveral. They are going to attempt a landing...maybe on land instead of the ASDS.

They've also got a geosynchronous sat launch in mid-July with the first "enhanced" F9 v1.1...that might have the capacity for a landing, which previous geosynchronous launches didn't have enough performance to attempt.

Comment: Simplified? (Score 5, Insightful) 100 100

"The Airbus team concluded that SpaceX's design of returning the full stage to Earth could be simplified by separating the propulsion bay from the rest of the stage, protecting the motor on reentry and, using the winglets and turbofans, return horizontally to a conventional air strip."

Interesting definition of "simplified" they're using. They're not even recovering the entire first stage, and they're basically bolting a jet airplane onto it to achieve that much. Propellant is as cheap as dirt, they're avoiding paying tens of thousands of dollars in propellant by instead paying for jet aircraft maintenance and operations and an entirely new set of cryogenic tankage and a substantial amount of aerospace vehicle structure for each flight. SpaceX is just making the first stage a bit bigger (and looking at things like additional propellant chilling to increase density) so it has the extra capacity required.

"We are using an aerodynamic shield so that the motor is not subjected to such high stress on reentry"

Thus solving an issue that SpaceX has already shown isn't actually a major problem...they have been regularly bringing entire intact first stages through reentry and down to sea level for some time now.

As for SpaceX not "coming close"...their second attempt actually brought the vehicle to a halt on the landing pad, though with mangled landing gear, and the reasons for the control issues during the final burn are well understood. They are extremely close...odds are quite good that their third attempt (in a bit under 2 weeks) will be a success.

Comment: Re:Hmm (Score 4, Informative) 39 39

The process involves liquefying the protein-containing material and running it through a fluid vortex that applies strong shear forces to the individual molecules, untangling them and allowing them to refold. This process is likely to be somewhat more detrimental to brain function than the mis-folded proteins were.

In this case, it appears the same shear forces cause the cancer drug to be more likely to get encapsulated in a lipid vesicle, which protects the drug and helps get it past cell membranes. Useful, but not directly applicable to Alzheimer's or prion diseases.

Comment: Re:Elon Musk to the rescue once again (Score 3, Informative) 105 105

The drone platforms (there's one being built for the west coast too) will still be used for situations where the core doesn't have enough propellant to return to land. Especially the center core of Falcon Heavy launches that need to make a large plane change, as the cross-fed center core goes much further and faster than the side cores.

If the facts don't fit the theory, change the facts. -- Albert Einstein

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