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Comment: I don't see the logic here (Score 3, Insightful) 52 52

A launch site at latitude L can launch into an orbit of inclination L *or higher*. You can launch into a polar orbit from anywhere on the planet. You can only launch into an equatorial orbit from the equator. Equatorial sites have the advantage, not high latitude sites. (Also, the hemisphere doesn't matter. Something launched into low Earth orbit from 45 degrees south will be at 45 degrees north in about 45 minutes time.)

Some technicalities:
Yes, you can launch into one orbit then change plane to a lower inclination later - but doing so in LEO is very expensive. (I think the cheapest way to do it is to put yourself into a high eccentricity orbit, do the plane change at max distance from Earth, then recircularize your orbit into LEO.) ('expense' = delta-v.)
Launching from latitude L also can't launch into retrograde orbits closer than L to 180 degrees. E.g. from latitude +/- 30 degrees, you can launch directly into orbits with inclination between 30 and 150 degrees.
If you specifically want a 45 degree inclination orbit, I don't know whether launching due east from a 45 degree latitude is cheaper or more expensive than launching either NE or SE from an equatorial site. I suspect there is no difference.

Comment: Re:Once Again (Score 1, Offtopic) 138 138

You know whats worse than todays pilots flying ancient airplanes, a brand new extravegantly expensive F-35 that cant match an F-16 or F-15E built in the 80s, planes built for a fraction of the price.

The F-35 might be an OK successor to the F-117 as a mostly stealth small bomber, but all indications are its completely worthless in a close in dogfight, you just have to read the leaked report from a recent test against an ancient F-16.

The F-35 simply doesnt have enough power, cant turn fast enough and bleeds off to much energy. The pilot found one manuever he could use to shake the F-16 but it consumed so much energy he had to run away and try to get the energy back.

The F-35 will also be horrible in the close air support role at which the A-10 excels, again at an even smaller fraction of the price tag.

F-35 is a classic jack of all trades and master of none.

There might have been a place for a few hundred of them but for the U.S. and every allied air force to think they are going to use one horrible design to replace every fighter they have is complete insanity. If it ever reaches full deployment, one accident or problem and the entire western world will have no air force. At least the Navy has the sense to keep the F-18 alive.

The F-35 is a tribute to the extent Lockheed has seized total control of Congress and the Pentagon, they could literally sell the Air Force actual turkeys for a hundred million a pop and get away with it.

Those B-52â(TM)s still flying today is because Northrop, has also seized control of the Air Forces generals made the B-2 so expensive and so few in number the Air Force canâ(TM)t afford to risk it in combat.

Besides the U.S. has been fighting people living in mud huts who have no air force and air defenses for over a decade, B-52â(TM)s and A-10â(TM)s work incredibly well in that role.

Comment: Overpressure in upper stage oxygen tank (Score 1) 49 49

Now he says "There was an overpressure event in the upper stage liquid oxygen tank. Data suggests counterintuitive cause."
"That's all we can say with confidence right now. Will have more to say following a thorough fault tree analysis."
https://twitter.com/elonmusk

Comment: How I saw it (Score 1) 49 49

Several minutes into flight, something that looked possibly like the Dragon capsule detached from the rocket and fell behind it. A few seconds later, the rocket disintegrated into fragments. The commentator on the SpaceX stream wasn't very informative (although their coverage was great up to that point, better than NASA's.)

NASA commentary has just confirmed that the vehicle has failed. (SpaceX have stopped streaming.)

Comment: Re:Infinity (Score 1) 1067 1067

I am not concerning myself with representations of mathematical values, except to show the parallels of why it works. IEEE 754 defines a positive and negative infinity, because it has a specific signed bit. Thus, it's easier to define a positive and negative infinity than to produce special code to handle "exceptions"... note also that IEEE 754 defines a positive and negative 0 separately. No, they really do.

My model is a theoretical one that hasn't reached mathematical consensus, and it likely never will. I just note that this is an argument for infinity being signless.

Comment: Re:Infinity (Score 1) 1067 1067

More importantly is what happens when you graph it: the limit of 1/x as x approaches zero is discontiguous. It's positive infinity when descending on the positive numbers, but negative infinity when ascending from the negatives. No one value can represent both!

Let's assume that the set of integers is Z_\inf. K? We can now define negative numbers as the 1's compliment of the number plus 1. 1 = 999...9998. then plus 1 = 999...9999. This plus 1 results in an infinite carry out, and the value 0. Awesome.

Now, let's look at 1/0, we see that from the right it's approaching \inf from the bottom, while we see that from the left, it's approaching \inf from the top. Now, at 0, obviously these two will be coincident, because we're working in Z_\inf, that value is the same value. Namely, -\inf = \inf. But that doesn't make sense, only 0 can be it's own negative!

But we've already known for a long time about Z_n where n is even, -(-128) in Z_256 is -128. -(-65536) in Z_2^16 = -65536. So, there's no trouble in making -\inf = \inf ...

Basically, 1/0 grows so fast that it manages to wrap around the entire infinite series of numbers. Which is exactly what it does...

Comment: Re:Infinity (Score 1) 1067 1067

That is simply false. There are an infinite number of algorithms that might contain the (sub)expression X/X for which zero is a valid value of X. To assume it's a programming error is sheer unmitigated stupidity that I might expect from a mathematician that has never written a real program in his life.

Dude... you perhaps haven't heard, but computers run entirely upon theoretical mathematics... I know, it's popular to say it's engineering, rather than mathematics, but it's mathematics. It's always been mathematics.

Comment: Who is getting fired for this? (Score 0, Flamebait) 266 266

Did I just read that right: the Obama administration just missed an opportunity to enact business-stifling, job-killing regulation? That the man who promised to heal the oceans is letting frackers get away with whatever they're doing?

Somebody's going to get fired over this. Fracking just has to be bad for the environment, because, well, big business (read: Republican leaning folks) are making money from it.

Comment: Non-stop? (Score 1) 85 85

As I recall, the first run of LHC was scheduled to run only 6 months out of 12, due to seasonal electricity price differences (although I think they abandoned that to get back on schedule after the catastrophic magnet failure.) Does anyone know if they're really running non-stop for three years, or is there significant down-time that the science reporter didn't know about or glossed over?

Comment: Re:MS Paint (Score 2) 290 290

Most, I hate the Sparta icon... it's white, with no contrast border... which makes everything that is assigned to it being the default program, show a white globe on a white background... it's like, "way to go, Microsoft!" followed by a slow clap.

"clean" "modern" design... which will never work decently on all backgrounds... you know... like good logos, and designs...

The star of riches is shining upon you.

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