Yep. Ignition seems to have happened right where the 2nd stage fuel lines attach, which is pinpointed by overlaying lines on the “starburst” from the overexposure.
SpaceX rockets & launches
It woz google!
Teeet from Elon Musk yesterday:
Still working on the Falcon fireball investigation. Turning out to be the most difficult and complex failure we have ever had in 14 years.
“Not ruling out” “an object hitting the rocket” apparently.
And they’re asking for any 3rd party recordings, audio or video.
It’s certainly a mystery.
Rumours and theories of deliberate sabotage, even!
Another Elon tweet:
Particularly trying to understand the quieter bang sound a few seconds before the fireball goes off. May come from rocket or something else.
The live presentation of spacex’s Mars plans is at 19:30. This is what the company was founded for. It’s the equivalent of “not because it is easy but because it is hard” from Apollo.
Of course you should be coming to the members meeting 
but if you can’t make it, you should be watching this instead.
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He needs a lecturn for his presenter notes. Oh, and – coo. To see something like that in my lifetime would be quite the thing. Tho’ fixing this planet still seems easier than whatever it will take for a Mars colony ahem self sustaining civilisation,
Here’s a fun number: 211GW - This is the maximum power output of the first stage of this rocket. To give some scale to that number, the UK electricity generation system works out around 40GW.
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To properly compare both figures I think a unit of time would also be needed.
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I choose 60 seconds
I think that’s UK GWh?
Well, no. Power is work per unit time. It makes sense to talk about instantaneous power output (although you may also talk about an average over an interval of time). According to this webpage:
http://www.gridwatch.templar.co.uk/
the total energy demand from the national grid at this moment is 37GW. The instantaneous demand could also be averaged over, for example, a day.
The rocket in question, therefore, will produce, while its first stage is firing, a power output equal to more than five times that of the British national grid. This statement is true at every instant for which the maximum burn rate of the fuel is reached. We can also say that over the total burn time of the first stage (if we make the assumption that the burn rate of the fuel, and hence power output, is a constant while it is firing) that it produces more than five times the energy output of the national grid over the same period.
Hence, it is when talking about energy output, and not power, when a time interval must be specified.
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Is that a unit of time?
It’s no time at all, but when you add them all up you get a finite amount of time.
As opposed to?
Well, a watt is 1 joule per second. Time is intrinsic to this, as it’s a measure of power and not energy, as has been said earlier.
P.S. I get the feeling that maybe this instantaneous concept of power supersedes the mundane joule per second thing?
A more intuitive understanding might be reached by making an analogy with speed and distance.
An analogous statement to the one which kicked off this conversation might be “I reached 40 miles per hour on my drive into work this morning. To give that number some scale, my walking pace is only 3 miles per hour.”
Do I need to specify an interval of time to compare the two speeds properly? Do I need to measure a distance travelled over something like a period of an hour, as implied by the unit of speed used? No. The needle on your speedometer moves around from one moment to the next but if you freeze time, it is pointing to some particular value. However, a distance can be traversed only over some finite interval of time.
Power is to energy as speed is to distance. It is acceptable to specify power, which is a rate of energy output, at an instant, much as it is with speed, which is a rate of distance travelled.
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I get it: a point on a graph!