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Comment Re:If the singularity doesn't happen... (Score 1) 26

First off, there is no "theoretical maximum speed" to how fast a given propulsion mechanism can get you. You can get to 0,999c by shooting tennis balls out the back of a spacecraft with a slingshot - if you're willing to build a spacecraft comparable in size to the universe ;)

Secondly, nuclear pulse drives really are an antiquated idea, I don't know why people obsess over it. Their minimum sizes are way too large and they're inefficient, with low ISP compared to more modern ideas. Longshot, BTW, is technically NPP, although a more modern variety. Still inefficient and very heavy, and nowhere close to a technology that could be achieved in a reasonable timeframe from where we are today.

Of the many, many concepts now available, I'd personally go for fission fragment propulsion. It's so straightforward: get the most out of fission by having individual fission reactions propel your spacecraft directly. And from a design perspective, it's pretty straightforward particle physics / fission reactor design, just in an unusual (suspended) configuration - the suspension already demoed in the lab. But that's, again, just one of many possibilities.

Comment Re:If the singularity doesn't happen... (Score 1) 26

Unfortunately, no. Their gravity is far too weak for them to provide a significant "slingshot" effect.

Also, the fact that there are many of them isn't really the big help that it might sound. One, there's many in a very large volume of space. Two, they have very different orbits. Even if two are physically "close" to each other in a given location at a given point in time, you still have a lot of delta-V to overcome.

Comment Re:Wow, and I thought the existing Sednoids were n (Score 2) 26

I don't think the process of exchange can be fast - if those bodies had galactic escape velocity, after all, they wouldn't stay here for long

They don't have escape velocity; they're stuck with us until something perturbs them. But the key point is that when something is that far out, it's very easy to perturb. And our stellar neighborhood is not static. Indeed, one of the alternative theories to explain the sednoids is that rather than a planet X, the orbits are due to one or more stellar passes nearby our solar system.

So far we're still not seeing very far out, we're just barely spotting these things, and only when they're near perihelion. There's much more out there yet to discover, and so far all signs point to that our solar system doesn't just "stop" anywhere, it just keeps on going. Heck, we only know about the Oort cloud because comets have such distant aphelions.

Comment Re:Wow, and I thought the existing Sednoids were n (Score 3, Interesting) 26

Looking at their graph (since I don't see the perihelion stated anywhere), it looks to be about 60 AU (about double that of Neptune). That's some tremendous temperature changes on that body! The equilibrium temperatures are:

((1368 / D^2 - 3.127e-6) / 4 / 5.670e-8 ) ^ 0.25 ... where D is the distance in AU. So at perihelion it'd be about 36K, but at aphelion only about 5K.

Now, this particular body is probably too small to retain significant hydrogen or helium, but you could imagine what it would be like for a large planetary one in such an orbit. It'd transition between being a hydrogen-ice planet with a helium mantle and water ice/rock core; and an ice giant like Uranus and Neptune. In its solid phase, its hydrogen-ice surface would be resurfaced entirely with every cycle and thus might be expected to be perfectly smooth, except because of the heat involved in the settling processes - and how low viscosity and structural integrity in general hydrogen ice has - I'd be willing to wager that you'd get helium volcanism and maybe even plate tectonics.

It gets even weirder if a planet at such distances as this one's aphelion were to have a moon that loses helium vapour to its planet (perhaps, for example, on an eccentric orbit getting it back at each perihelion as the planet inflates, to repeat the cycle at the next aphelion). After all, even below the boiling point, there's always some vapour pressure for helium. If you're taking that vapour away, then you're looking at evaporative cooling, and you really don't need to lose it that fast to cool to below the cosmic microwave background (because radiative exchange is so slow at those temperatures) and thus to helium's lambda point. Now you have a body with superfluid helium on it, and all of the crazy weirdness that superfluids do.

Back to our solar system - aka, a small body like 2014 FE72 - you're not going to have much hydrogen or helium. But even still, that crust is going to be going through some crazy thermal stresses at the very least. Also, neon - while not as common as hydrogen and helium, but should be more common in the outer reaches of our solar system than the inner - would pass through all three phases (melting point 24K, boiling point 27K at 1 bar; lower at reduced pressures). I wonder what sort of minerology neon would form? "Neonothermal" crystal veins, analogous to crystals in hydrothermal systems on Earth? :)

Comment Wow, and I thought the existing Sednoids were neat (Score 2) 26

A sednoid (2014 FE72) with an orbit out to 3000 AU (0,05 light years)? Talk about extreme, I would have been happy just for a couple more "ordinary" sednoids! But that's exactly the sort of thing you want to see if you're of the view that trying to group the universe into a neat collection of "stars" with "planets" orbiting them is oversimplistic. This lends credence to the notion that you're going to get shared debris between different stars, rogue planets that don't orbit stars, etc. Because with large bodies reaching that far out, it becomes pretty easy to perturb them to leave the solar system altogether.

I have no clue what the discovery of 2013 FT28 is going to say about the possibility of an additional large planet in our solar system, but I look forward to the papers on it! Hopefully it won't rule one out, and will instead better constrain an orbit

Comment Re:problems, lol (Score 1) 122

Or, you know. You could actually learn how to write good code at the most powerful level. That's a radical thought.

I did, and that's why I'm using Python. I'm capable of writing web services in C, but who the hell's got time for that craziness? Also consider Amdahl's Law: in most of stuff I write, the "running code to process data" bit is a teensy portion of wall clock time. Much more is spent in socket handshaking or waiting for database queries to finish. Out of a 50ms request lifecycle, perhaps 1ms is spent inside a box that I have complete control of. Even if I rewrote it in assembler (C is for high-level pansies) to be 1000x faster, the request would still take 49.001ms. An assload of work porting security-sensitive code into an untyped languages so that the end result can be 2% faster? Yeah, no. My boss would fire me with a quickness if I proposed that.

I'd be much more likely to rewrite performance-critical code in Go or Rust. They're as fast as C but without the death of a thousand cuts like gotofail waiting to ruin your careful planning. Life's too short to waste it hacking in languages that hate you and make you want to look incompetent.

Comment Re:America in one sentence (Score 1) 431

Those jobs mostly exist for people bad at math. Kinda like sometimes a business will make a desperate play of selling below cost as a desperate ploy to make payroll one more month. It usually doesn't work out.

There are people that incredibly lazy, but there's less of them than you might think.

Comment Re:Come the fuck on (Score 1) 350

The more versatile part is you can add disks one at a time to btrfs when mirroring and have it make reasonable use of it. If a disk fails and there's enough room left over you can even rebalance on an odd number of drives and be fully redundant until you can get another disk in. All of that together means you can upgrade to new bigger disks without going offline (naturally, performance takes a hit during the upgrade).

At the same time, I also have ZFS in production and no intention to migrate.

Comment Re:Unsustainable pricing on high tech gadgets (Score 1) 97

It doesn't cost $800 to manufacture an iPhone. More like $100. In the US it would maybe be $150. It is Apples greed that is the blame.

There are always lines around the block on launch day. People cheerfully buy tens of millions of each iPhone. If people are willing to pay that price without a gun to their head, and there are alternatives that they could buy instead but they choose to buy iPhones anyway, how do you justify describing it as greed?

Comment Re:America in one sentence (Score 2) 431

My favorite new testament verse: 'If someone won't work, they shall not eat' (para).

Given that at that time, the poor were permitted to help themselves to the edges of the fields, that made sense. If you couldn't even be bothered to go harvest what you needed (assuming you were able), then yeah.

Of course, too many confuse won't work with can't work and no employment available that pays more than it costs.

Submission + - Lost Doctor Story to be released as animation

BigBadBus writes: The lost 1966 Doctor Who story, "The Power of the Daleks" is to be released in an animated version according to the UK Mirror Newspaper. The story is significant as it is the first story to feature the newly regenerated Doctor, starring Patrick Troughton. However, only a few live action clips exist from the story. For weeks now, BBC Worldwide have issued takedown orders to anyone leaking animated clips on YouTube.
There are still 97 live action episodes missing however; the last were unearthed in 2013.

Comment Re:The MS Merry Go Round. (Score 1) 212

Yep and I'll be advising customers to disable updates, which won't be an issue since the browser runs in a sandbox and all web pages are scanned before load.

Meanwhile all my business customers are looking at exit strategies, some looking at Apple, some looking at Linux with a Windows VM for the Windows centric software that is required. All MSFT is doing is shooting themselves in their face with this dumb shit because a desktop is not a cellphone and the shit people will put up with on a cellphone the majority will NOT put up with on a desktop. I should know as uninstalling windows 10 is frankly one of my most popular services, it even surpassed Win 8 uninstalls awhile back, its just too fucking buggy.

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