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Comment Re:Verizon did this as well (Score 1) 88

"Oh, bullshit. You've fallen for marketing. No one voted them in charge of the dictionary"

This is not how standards bodies work.

NGMNA is simply a working group of mobile networks and handset makers who sit around and come up with a set of standards as to what will be called "5G". For 4G they settled on the LTE family of protocols of which LTEX is one of those standards. They are recognized by governments, standards super-bodies such as the IEEE, the mobile handset makers and the networks. Thats as close to "voted in" as your going to get.

No you dont get a say in it, unless your making handsets or own a mobile network, anything else is solipsist nonsense. Words actually have meanings dude, and they are not "Whatever I stamp my feet and demand to be true".

NGMNA's current prototype is based around the Snapdragon X50 modem which runs in the mm range (around 28ghz range) and supposedly can operate at a burst bandwidths of 35gbps.

Which is actually ridiculous and I have doubts they'll give consumers that much to play with. But a "generation" in mobile networks is around ten years, and we're still a long way off anything the NGMA and its member companies will agree on as worth locking in for a decade as a standard

Comment Re:Illegal labor (Score 1) 93

If picking fruit paid more and had more benefits than programming, I would have no problem picking fruit on the side.

If jobs picking fruit paid that much, the fruit would be so expensive that nearly nobody would buy it, and therefore nearly nobody would grow or sell fruit. I don't think destroying the agricultural industries of the US will be considered an acceptable solution by anyone.

Comment Re:Speaking of delays... (Score 1) 106

ULA's track record with the Atlas V: 100%

Yes, let's take one vehicle in its fifth generation (not counting subrevisions), and ignore its track record with all of its earlier versions that led up to this point and all of their failures, and all of Lockheed and Boeings' other launch vehicles over time, with all of their failures. Lets also ignore that they're going to have to switch engines soon, to an engine with zero track record.

Payloads typically launch on schedule or within a few weeks. .... Some payloads have been waiting literally years due to delays.

Let's totally ignore that Atlas V launches once per two months, while SpaceX launches once per month, and that almost all of the wait time was due to investigation backlog. When it comes to hitting launch windows, SpaceX has a higher average success rate than average than Atlas V

And lets entirely fail to mention the point that ULA charges nearly double what SpaceX does per kilogram. Or that SpaceX is doing everything while rapidly evolving its rocket, to the point that they've basically even switched propellants partway through (denisification radically changes their properties). And while at the same time running an aggressive recovery and refurbishment programme and developing a heavy lift vehicle, with a small fraction as much capital.

Comment Re:What governmen brought to the table (Score 1) 106

As if liquid boosters can't fail catastrophically? Check out SpaceX's last failure. Liquids are hardly immune to catastrophic failure.

And actually more to the point, you've got it backwards. The SRB failure on Challenger was slow, more like a blowtorch. The explosion was when it compromised the external tank (which, obviously, stored liquids).

Solid propellants aren't like explosives. More to the point, you have to keep them under pressure to get the sort of burn rate that is desired for a rocket.

Comment Re:Speaking of delays... (Score 2) 106

Could you remind me how many people SpaceX has killed? Boeing and Lockheed have certainly killed people in the past.

If you're referring to the AMOS 6 ground failure, ignoring that part of the whole point of flying a stack unmanned as much as you can before you fly it manned is to shake out any problems, is that a manned mission would have almost certainly survived that. Unless the launch escape system failed, despite the drama, that was an eminently survivable. How do we know this? Because AMOS-6's hypergolic propellant tanks didn't ignite until the satellite hit the ground. AMOS-6 had the fairing as some extra protection, but on the other hand, the satellite itself isn't nearly as durable as a crew dragon.

The launch escape system ignites within milliseconds of a failure being detected and almost immediately reaches full thrust, accelerating away at 10gs. Here's a graphic of Dragon's abort test superimposed over the AMOS-6 failure. Things like this are the very reason that launch escape systems exist. NASA's last manned space vehicle lacked such a system entirely. And while their design for the Shuttle ultimately wasn't chosen, you know what? Lockheed's proposal didn't have one either. And it had a strong impact on influencing the final Shuttle design outcome.

Comment Re:What governmen brought to the table (Score 1) 106

SpaceX and Blue Origin would not use solids, not because there's something wrong with solids per se, but because they're not "fuel and go", which makes them expensive to reuse - and SpaceX and Blue Origin are all about reuse.

A lack of experience with hydrolox surely factors into the picture for SpaceX and Blue Origin; they'd get significantly higher payload fractions by using a hydrolox upper stage. But they're willing to accept lower payloads in order to simplify their manufacture and ground infrastructure, and in particular because the need their propellants to be storable, and storing LH for long periods is a PITA. Storing methalox is quite difficult, but nothing compared to hydrolox.

Comment Re:What governmen brought to the table (Score 2) 106

Solids really aren't that bad when reusability isn't a concern. They're very high thrust, which is exactly what you want out of a booster, and they're structurally very simple. Their low impulse and high structural mass are not particularly important aspects for boosters. Reuse of solids however gains you very little, because there's so much work in refurbishing them.

Comment Re:What governmen brought to the table (Score 3, Informative) 106

That's not the reason you don't use it for a first stage. The disadvantages of hydrolox (which are numerous) are offset by its incredible specific impulse. But for a first stage, specific impulse doesn't matter that much, while thrust matters a lot. Thrust is in large part proportional to fuel density, as a turbopump sweeps out a fixed volume per rotation, so the denser the fuel, the more mass (and generally all else being equal, energy) it pumps per rotation.

Another aspect is that first stages are big, meaning that cost is more important than specific impulse. By contrast, when dealing with an upper stage, a small increase in mass has a huge increase in first stage size, and since first stages are so large and expensive, that's a big cost. So you generally want a higher ISP upper stage. With the caveat that "storability" requirements for engines that need to restart can shift the balance; because hydrogen is so deeply cryogenic it's difficult to store for protracted lengths of time. Also, the longer you plan to have a stage in usage without maintenance, the more you tend to favour simple propellants over high performing ones, particularly when you're dealing with small, light engines. So for example if you have an interplanetary probe you'll tend to favour a self-pressurizing hypergolic system so that you only have to rely on a couple valves working, even though self-pressurizing propellant tanks are heavier and hypergolics tend to be lower specific impulse. Engines that are smaller still are often monoprops for an even greater degree of simplicity.

Comment Re:Verizon did this as well (Score 2) 88

No, the 5G network will be what the The Next Generation Mobile Networks Alliance (The guys who actually define this, being the telco working body in charge). Its a work in process and all the stakeholders agree on that much.

My iphone 7 gets 127mbps/s8.87mbps. Thats 4G

5G research is including things like milimeter wavelength coms (20+ghz) and likely will crack the 1gbps barrier.

Comment Re:Uh huh. (Score 2) 88

Getting the actual people there (and back) is the costly part. "Stuff" doesn't require four or five levels of fail-safe. "Stuff" doesn't need to take a shit or get sick or argue about politics.

Then the solution seems pretty straightforward: send only "stuff" up there for the first few years.

Once the "stuff" has organized itself (because robots) and is looking pretty good, then send up some human beings, if you still want to. They can walk right into to their prefab moon-hotel.

Comment Re: Unlikely (Score 1) 232

We heard the same sort of claims made about climate 'science'. We were told that 'the science was settled'. Then it turns out that it actually wasn't settled at all. There was much to be doubtful about. The accuracy of measurement techniques became doubted. Questionable assumptions were made. Data had to be 'adjusted' to fit models. All in all, it left a bad taste in the mouths of people who strive to apply the scientific method rigorously and properly.

Anthropic climate change is very much "settled", except in the minds of conservative conspiracy theorists who's opinions don't count towards "the scientific consensus" (Principally because they are wrong).

Where was the data "adjusted". Time and time again when these claims where made, when people look into it, the evidence disapears. And "the measurements" are the same.

The whole "urban heat island" thing was unscientific nonsense thats been debunked time and time again. And that whole "hide the decline" nonsense was a specific case where a known deviation from observations regarding arctic tree ring samples in the 50s (Likely from nuclear testing pounding the trees in the area with radiation) was removed from a dataset to make the data *MORE* accurate.

But hey, why let the facts get in the way of a good conspiracy theory.

As for dating, we're talking Thorium/Uranium dating here, which is very robust to the time span we're refering to with an accuracy to within 1% (Much better than the 1std-deviation of carbon).

All of these figures fall out the apriori calculations that derive from fundamental physics and observation.

Much like modern climate modelling, actually.

Comment Re:Unlikely (Score 1) 232

Another problem is the new date is almost an order of magnitude older than all prior evidence. One isolated sample set is not sufficient evidence to revise the estimate that much. We'd need more samples from the likes of say 40k and 90k to give more credence to the 130k date.

Needing samples from other dates is unnecessary. A quick search of the journals will show thousands of samples from various time periods tested with the method. Its a solved problem.

More samples from the *same* source however will reduce the error margins

Comment Re:Unlikely (Score 2) 232

Nah. These new methods aren't accurate either. Everyone said carbon dating was accurate for decades, but it really wasn't. Don't believe everything you read.

Where are you getting this guff from? Carbon dating is precisely as reliable as it always has been, within one standard deviation. We've always known that, and the accuracy can be derived a-priori from fundamental physics.

There are more accurate methods, but all are basically derived from the fundamental determinism that radioactive decay occurs at a predictable rate.

Source: I dont read creationist propaganda.

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