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User: Tango42

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  1. Re:hubble? on LBT Publishes "First Light" Image · · Score: 1

    Precisely - none at all.

  2. Re:In other words... on Gates Donates $15M to Preserve Computing History · · Score: 1

    They're buying free publicity? Odd definition of free...

  3. Re:Only 200GB? on 200gb Hack for iPod Nano · · Score: 1

    Ok, so I don't know the difference between a megabyte and a gigabyte... that's pretty bad.

    My point still stands though - 1000 times more so, in fact...

  4. Re:Only 200GB? on 200gb Hack for iPod Nano · · Score: 0

    Floppies aren't cheap though... I quick google finds floppies selling for about 30 cents each. That's 0.3/1.44=$0.21/MB.

    A 200GB hard drive costs around $90, that's 90/200=$0.45/MB

    A hard drive is only twice the price of a floppy, per MB. If you want a different floppy drive for each floppy, the price increases from $0.30 to over $5... no longer cheap in the slighest.

  5. Re:Batteries produce power on Silent 500W Power Supply · · Score: 1

    The mains supplies power to the PSU and the PSU supplies power to the PC. It does that by converting it, but so does everything else that produces power, or anything for that matter.

    Would you say Intel don't produce processors? By your logic they just convert the component parts into processors.

  6. Re:24 Mb not 24 MB on 24 Mb Consumer Broadband Launched · · Score: 1

    All network speeds are given in bits/s not bytes/s so there's not room for confusion, really. You only need to know the difference what you look at download speeds which seem to be given in bytes/s.

  7. Re:Shape and orbit on How Would You Define a Planet? · · Score: 1

    Rogue Planet? Big rock? It would just be a large dead rock/ice body - any atmostphere would have frozen away, so you could have a body much large than earth but with no atmosphere... that probably doesn't effect the definition, but it's interesting.

  8. Re:anything with a roman god name on How Would You Define a Planet? · · Score: 1

    Does that translate to "folks from French call their home planet England"? So, bad grammer, and we English have big enough egos as it is... elevating our status to "planet" won't help.

  9. Re:That's the key though... on Thoughts on the Space Elevator · · Score: 1

    I looked up the density of diamond and multiplied by the volume to get the mass.

    The mass of air displaced will reduce proportional to the pressure decrease, I think... I can never remember the gas laws... let me ask wikipedia. Yeah, assuming constant temperature (which is complete rubbish, but I'm doing back of an envolope calculations here, so it'll do) it's directly proportional. To give you an idea, the pressure at 20km above sea level is half that at sea level, and LEO starts at 200km (where the pressure is essentially 0 - that's what LEO means), so you're idea is practical to get you off the ground, but it won't get you very high.

    I've just looked it up, and weather balloon style balloons, filled with helium can reach 50km. Your idea would struggle to get that high. So basically, it would work, but it's far easier to use a weaker and lighter material and fill it with a lighter than air gas than to use a vacumn.

  10. Re:Elevate me up Scotty! on Thoughts on the Space Elevator · · Score: 1

    Yes, you'd drop, but then you'd go back up again - that's how an elliptical orbit works. As you drop you increase in speed to the point that you start rising again.

  11. Re:That's the key though... on Thoughts on the Space Elevator · · Score: 1

    I'm not sure if it will work or not... the mass of the air removed would have to equal the mass of the diamond+cargo, and the mass of the air would reduce as altitude increase and pressure decreases. That would make it useless for getting very high, but it might work to start off and use a rocket later...

    I'll do some rough calculations and some googling.

    A practical size for this bubble might be 100m diameter (we're just looking for an order of magnitude here, so 100m will do - you could probably get bigger if you really wanted to). The surface area for a 100m sphere is 4*pi*100^2=126000m^2 (roughly). Assuming a thickness of 1cm (I can't be bothered to work out the thickness needed), and the density of diamond being 3.5g/cm^3 the mass of the diamond would be nearly 5000 tonnes.

    The volume of this sphere is about 4,000,000 m^3. 5000 tonnes/4000000=1.2 kg/m^3. Which is pretty much exactly the same as the density of nitrogen at sea level... so I guess it is vaguely practical.

    A good lunar colony, of course, wouldn't need large amounts of stuff transported - it would need to be self sufficient to last any length of time.

  12. Re:Hmmm.... on Thoughts on the Space Elevator · · Score: 1

    The laws of physics force you to build it near the equator - I don't think you can get hurricanes near the equator, although that might just be tornados...

  13. Re:another engineer's perspective on Thoughts on the Space Elevator · · Score: 1

    Counterweight isn't a very good word - countermass is more appropriate. It's inertia rather than gravity that you need to consider for the counterweight.

  14. Re:Elevate me up Scotty! on Thoughts on the Space Elevator · · Score: 1

    You wouldn't drop all the way to the ground, would you? Wouldn't you just end up in an eliptical orbit with the point you let go as the apogee? As long as you get high enough for the perigee to be out of the atmosphere, you'd be fine.

  15. Re:It may be more cost effective technically.. on Thoughts on the Space Elevator · · Score: 4, Interesting

    Actually, it's more than Geosynchronous - the centre of gravity needs to be at GS (or near it, the fact that it's joined to the ground might have an effect), so it has to go past it by an amount depending on the mass of the counterweight.

  16. Re:Stephens theories,.... on Black Hole in Search of a Home · · Score: 1

    You didn't reply to that post though.

  17. Re:Stephens theories,.... on Black Hole in Search of a Home · · Score: 1

    So actually, that's "yes", not "no". Just because the GP wasn't very detailed doesn't make it wrong...

  18. Re:Stephens theories,.... on Black Hole in Search of a Home · · Score: 2, Informative

    You mean Hawking radiation? From what I remember, Hawking radiation is inversely proportional to the size of the black hole, so the radiation emited from a supermassive black hole like those in Quasars is almost non-existant.

  19. Re:20 million for a week? on Russian Cargo Ship Docks At ISS, Preps For Tourist · · Score: 2, Funny

    I'd rather stay... $50 mil for a week, $20 mil for ever...

  20. Re:methane? on Titan Occupies A Solar System Sweet Spot · · Score: 1

    True, but not relevant. Titan doesn't have enough of anything else either.

  21. Obvious on Windows Vista To Come In 7 Flavors · · Score: 4, Interesting

    It's obvious why they've done it. Now whenever someone complains that windows in too expensive they can say "But we've got cheap version if you want them", so they can charge much more for the better version, knowing perfectly well that nobody will ever actually use Starter Edition, even if it is half the price.

    3 applications? That that include background utilities like virus scanner and firewall? What about IM? So I have AVG, Zonealarm and Trillian running (did I pick the right ones? those are the current choices on /., yes?), so i can't run anything else, not even a browser.

  22. Re:methane? on Titan Occupies A Solar System Sweet Spot · · Score: 1

    You don't choose your equations, you have to stick with what actually happens. You put a match the methane it reacts with oxygen to produce CO2 and water, that's what happens, you don't get to choose. You're right, that won't work in space, that's why methane won't burn in space, which was my point - Titan, taken as a whole, is in space.

  23. Re:methane? on Titan Occupies A Solar System Sweet Spot · · Score: 1

    I didn't say it couldn't be metabolised without oxygen, I said it couldn't burn - lighting a match is usually used to stand fire, not life... interesting twist on Frankenstein if it was.

  24. Re:methane? on Titan Occupies A Solar System Sweet Spot · · Score: 4, Informative

    Methane only burns in the presence of oxygen, there's not enough oxygen on Titan for that. You'll have to go back to mailboxes.

  25. Re:The problem with multiple-guess tests on Tools for Automated Grading? · · Score: 1

    The sorting method is completely separate from the correct answer. The distribution of letters will skew the sort, but the correct answer won't be in a specific place in that sort. The wrong answers follow the same distribution as the correct.