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Comment Re:What governmen brought to the table (Score 1) 66

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 1) 66

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 2) 66

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.

Submission + - Neandertal and Denisovan DNA from Pleistocene sediments (theatlantic.com)

ISayWeOnlyToBePolite writes: The Atlantic reports https://www.theatlantic.com/sc... that Viviane Slon from the Max Planck Institute for Evolutionary Anthropology and her colleagues have now managed to extract and sequence the DNA of ancient animals from sediment thatâ(TM)s up to 240,000 years old. By creating a molecule that binds to mammal DNA they have been able to sort out Denisovan, Neanderhal, mammoths, woolly rhinos, and cave bears from cave sediments at a previously unprecidented scale. Paywalled science article http://science.sciencemag.org/...

Comment Re:Poster does not understand Algebra (Score 1) 353

I mentioned that point, and how it completely ignored the point I was discussing, and how I was going to ignore it in turn. Two people starting out life with different amount of wealth, and the consequences of that on who can lend at interest and who has to borrow at interest even given the otherwise exact same preferences and abilities, has nothing whatsoever to do with "the choice to defer consumption". You're assuming that that is always the cause of differences in wealth, and so justifies the consequences of such differences, when it very obviously is not always or even usually the cause, so arguing whether or not it would justify the consequences if it was the sole cause of them is a moot point. It simply isn't, and there's no sense arguing about what if it were.

Try addressing the actual argument next time.

Tu quoque.

Submission + - NASA officially delays SLS first flight to 2019 (arstechnica.com)

schwit1 writes: Despite spending almost $19 billion and more than thirteen years of development, NASA today admitted that it will have to delay the first test flight of the SLS rocket from late 2018 to sometime in 2019.

“We agree with the GAO that maintaining a November 2018 launch readiness date is not in the best interest of the program, and we are in the process of establishing a new target in 2019,” wrote William Gerstenmaier, chief of NASA’s human spaceflight program. “Caution should be used in referencing the report on the specific technical issues, but the overall conclusions are valid.”

The competition between the big government SLS/Orion program and private commercial space is downright embarrassing to the government. While SLS continues to be delayed, even after more than a decade of work and billions of wasted dollars, SpaceX is gearing up for the first flight of Falcon Heavy this year. And they will be doing it despite the fact that Congress took money from the commercial private space effort, delaying its progress, in order to throw more money at SLS/Orion.

Comment Re:Most didn't (Score 1) 531

You can tell a true idiot by someone who spend all their time spouting that one is clearly superior to the other

You can acknowledge that two sandwiches are both literally full of shit, and preferably neither should be eaten, without also denying that the HIV-infested steaming fresh human shit sandwich is clearly even worse than the dry cow pie sandwich, as bad as the latter may also be. In fact you could "tell a true idiot by someone" who'll vehemently swear that they're both equally bad.

Comment Re:COBOL isn't hard to learn (Score 4, Interesting) 305

Indeed. If there is a market for COBOL programmers (and it's clear there is), then the obvious solution is for unis and colleges to spit out more COBOL-literate CS graduates. Honestly, if I was ten years younger, I'd probably delve into it myself. It is, after all, just a programming language, and hardly on the same level of trying to learn Sanskrit.

As long as you have a real fall-back so your career doesn't dead end. What can easily happen is that you do X then more of X because it's the only place you get a salary/career development until you've done X so long nobody will really hire you for anything else. I see this with for example some SAP consultants, essentially SAP customers want to hire you for your SAP experience and the rest of the world doesn't care that you have a general IT degree 5 or 10 years ago because your experience is all SAP-specific and they don't run SAP.

Now they're probably safe since that ERP is burrowed so deep into many companies they'll never get out, but for something like COBOL you could end up doing it for some years and then the legacy system is shut down and nobody wants to give you anything but a junior non-COBOL position. That is if they'll even hire you or if they'd rather have a recent college graduate. Or you might have to relocate to find one of those increasingly rare positions that actually value your COBOL experience, which of course only makes it harder at the next crossroads.

If you write cell phone apps as a hobby and can show them a portfolio or something, maybe you'll get away with it. No, you're not a dinosaur who only knows an outdated language and best practices from 50 years ago. Or some other way to be able to transition away from that COBOL career more smoothly. Some of my older colleagues noted that the parking inspector at work used to be COBOL programmer some 20 years ago, they updated their skillset and apparently he didn't.

Comment Re:FP becomes more popular than OOP? (Score 1) 415

The industry learned the hard way that OOP works well for some things but not others. For example, OOP has mostly failed in domain modeling (modeling real-world "nouns") but is pretty good at packaging API's for computing and networking services.

The industry may also learn the hard way where FP does well and where it chokes. Some understandably don't want to be the guinea pigs.

Comment Re:Functional Programming Considered Harmful (Score 1) 415

If you work on Chevies when everyone else is working on Fords, then you may have difficulty finding mechanics for your customized Chevies. I've yet to see evidence FP is objectively "better" in enough circumstances and niches to justify narrowing staffing options except for certain specialties. (I've complained about lack of practical demonstrations elsewhere on this story.)

Submission + - DNA-Based Test Can Spot Cancer Recurrence a Year Before Conventional Scans (theguardian.com)

An anonymous reader writes: A revolutionary blood test has been shown to diagnose the recurrence of cancer up to a year in advance of conventional scans in a major lung cancer trial. The test, known as a liquid biopsy, could buy crucial time for doctors by indicating that cancer is growing in the body when tumors are not yet detectable on CT scans and long before the patient becomes aware of physical symptoms. It works by detecting free-floating mutated DNA, released into the bloodstream by dying cancer cells. In the trial of 100 lung cancer patients, scientists saw precipitous rises in tumor DNA in the blood of patients who would go on to relapse months, or even a year, later. In the latest trial, reported in the journal Nature, 100 patients with non-small cell lung cancer were followed from diagnosis through surgery and chemotherapy, having blood tests every six to eight weeks. By analyzing the patchwork of genetic faults in cells across each tumor, scientists created personalized genomic templates for each patient. This was then compared to the DNA floating in their blood, to assess whether a fraction of it matched that seen in their tumor.

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