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Comment: I don't see the logic here (Score 3, Insightful) 71 71

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: 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: 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: SSC? (Score 3, Interesting) 52 52

The Superconducting Super Collider would, if not cancelled, have had 40TeV collisions about 15-20 years ago. The LHC is using computing resources that are very challenging to supply in 2015, exceeding what would have been achievable for SSC by a factor of perhaps 1000 (15-20 years of Moore's Law.)

Had SSC been completed, would the computing and detector technology have been able to make effective use of the collisions? Was it in fact a correct decision to abandon it at that time? Would the much higher collision energy have reduced the detection/computational load in some way? (E.g. higher signal to noise, leading to needing many fewer collisions.)

Comment: 941A? (Score 1) 17 17

The allusion in 451 Bradbury St is obvious to me, so now I'm wondering whether there is some significance to #941A? Have I just had my geek card revoked for not knowing it?

(Most /. readers will be aware that the allusion is to the novel "Farenheit 451" by Ray Bradbury.)

Comment: Re:Price won't come down (Score 2) 317 317

So I'm looking at the lithium price and I see that for $64M I can make a plant/mine which will give me $8M/year profit, and ROI of 12.5%. This looks pretty good. Then I consider than some bright spark might come up with an aluminium based battery technology which would make lithium ion batteries obsolete and could be in production 4 years from now. If this were to happen, in four years I've made back just $32M and now have a worthless mine. Therefore I decide not to invest in lithium production until I can get ROI of 20% because of the risk.

It seems to me that lithium is bound to be either overproduced (if new technology comes along) or underproduced (if new technology does not, but investors are wary of building facilities for fear it might.)

Comment: He was also the second Governor of New Zealand (Score 4, Interesting) 33 33

He quickly became very unpopular with settlers due to trying to be fair to the Maori. In one notable occasion some colonists invaded Maori land in an attempt to seize it and got massacred. (They were a poorly armed militia and on the other side was Te Rauparaha, who was so scary that to this day his haka is used by the All Blacks to intimidate their opposition.) After an investigation, Fitzroy sided with the Maori.

Comment: The grid needs storage - not battery storage (Score 4, Informative) 334 334

There are many ways to 'store' electricity. Batteries are just one.

I rather like this one, a thermal storage solution. Putting air into and out of bladders under deep water is a very simple method, as is moving water up and down hills. Then there are flywheels and fixed volume compressed air storage. (The air bladders above are fixed pressure compressed air storage.) There other thermal storage possibilities, but getting good round trip efficiency is tricky.

There are non-traditional battery techniques too: flow batteries (liquid electrolytes in tanks, adding storage capacity is as easy as adding tanks full of electrolyte) and molten metal batteries (take the idea of aluminium smelting and make it reversible).

All the non-battery alternatives I can think of work at industrial scale, so if you're looking for a household/small business solution, I think that at least for now batteries are it.

Comment: Re:Managers & HR take note (Score 5, Insightful) 124 124

There are three lessons here. One is about arbitrary work requirements, which you've made well.

Second is the problems which arise when vertical integration in your company means that one level's customers are another level's competitors. This conflict of interest is liable to drive away customers. (A company my father worked for many years ago had a similar issue: one branch manufactured and sold refrigeration equipments and spare parts. Another branch maintained and repaired refrigeration equipment, so their competition was the manufacturing branch's customers. The maintenance branch was separated into a new company to avoid this problem.)

Third is when you have a large corporation with an innovative product, that innovative product's potential can easily be crippled by being held hostage to vested interests of other parts of the corporation.

Reality must take precedence over public relations, for Mother Nature cannot be fooled. -- R.P. Feynman

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