My guess is that it is a detection issue, but I figured I would ask if anyone had a more qualified guess than what my gut tells me
Ask and answer stupid questions here! - Page 667
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Ghostcom
Denmark4776 Posts
My guess is that it is a detection issue, but I figured I would ask if anyone had a more qualified guess than what my gut tells me | ||
Gorsameth
Netherlands20770 Posts
I assume it uncertainty of the time is simply because they don't know all the exact variables to have a completely accurate speed. | ||
Oshuy
Netherlands529 Posts
Detection of the flare is the easy part: the flash of the flare is monitored and you see it ~8min after it appears. Nasa provides the images. For example, the 2 flashes of wednesday : www.nasa.gov (prediction of the flare is a tricky one) The aurora borealis appears when the ejection of particles linked to the flare hits earth. There are always particles coming from the sun (solar wind), with an average speed of ~450km/s. This speed can vary from <50km/s to >1000kms/s. To give a precise date/hour for the aurora, we need either a predictive model for the solar wind speed or a set of probes monitoring its value on the way. Nasa states "the strongest flares are almost always correlated with coronal mass ejections" and an article from 2014 states "We have determined positive corelation between magnitudes of geomagnetic storms and ... jump in solar wind plasma". Not exactly close to a precise model yet. We currently have a few probes monitoring the sun and the solar wind (at least at L1 and at sun level) which provide some information, but not enough to be very precise either. Current solar wind speed displayed on noaa has varied from 695km/s to 760km/s while I type this post (already up to speed for the first flares of the same area on monday). If we just take those min/max speeds as reference, it would mean 54h to 59h travel time, so event at 14:30 on 07/09 would be seen between 20h30 on 09/09 and 01:30 on 10/09. It is more than a bit arbitrary as speed might change in the coming hours, but I could not find much more exploitable information. | ||
Ghostcom
Denmark4776 Posts
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Oshuy
Netherlands529 Posts
On September 08 2017 10:45 Ghostcom wrote: Thank you - this was a bit more of the info I was looking for. Any particular reason why a "closer" eye isn't being kept on the sun? Money? Or is it really just not that "interesting" compared to much other stuff? Update : wind peaked above 800km/s, KP displayed at 8,67 ; potential aurora seen above most of eastern Canada, northern atlantic at New York/Paris latitudes and Scotland/Norway in the coming hours. I don't have the knowledge to answer. I would say there are eyes monitoring the sun and quite a bit of money invested in it. We would need an incentive to do more. Currently probes at sun level for the predictive model and probe at L1 to give an advanced warning for satellite protection. Any new mission is in the hundreds of millions range, so you need quite a bit of justification. (there might be a replacement planned next for the existing ones launched in 2006, not sure) | ||
Ryndika
1489 Posts
I love teamliquid to death from 8+yr lurkingso I wonder where this kind of place has gone. I did found the actual irc channel but I wonder why it's removed now. | ||
Zambrah
United States6832 Posts
Any quick solutions to this so I can get a good night's sleep before I have to go to work like this tomorrow? | ||
Uldridge
Belgium4255 Posts
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Zambrah
United States6832 Posts
On September 11 2017 09:41 Uldridge wrote: Have you tried swallowing? Makes me nauseated | ||
JimmiC
Canada22817 Posts
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Epishade
United States2267 Posts
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Ghostcom
Denmark4776 Posts
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AbouSV
Germany1278 Posts
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GreenHorizons
United States21793 Posts
Like what's that about? | ||
JimmiC
Canada22817 Posts
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heyitsMiro
83 Posts
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Simberto
Germany11033 Posts
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Artisreal
Germany9227 Posts
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Navane
Netherlands2694 Posts
(Just before midnight)(on thursday) is unambiguous. So now as a listener you can choose to perceive this sentence as unambiguous on thirsday, or ambiguous. It the situation is not severe, it is human custom to interpret the unambiguous version. Otherwise man would have to communicate in legal language or programming language, which can be a lot more verbose than the normal, fuzzy human language. If the situation is severe, ask to elaborate. | ||
Fecalfeast
Canada11355 Posts
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