Wednesday (depending on where you live) there was a solar flare. Supposedly some of the particles will hit earth Saturday evening at 19:30 CEST and there is thus a chance of aurora borealis in Denmark (which is fairly rare due to how far south we are). However, supposedly there is an uncertainty concerning the exact time so in actuality the particles will hit at 19:30 +-7 hours. It's this uncertainty that I'm unsure where stems from as it isn't explained in any of the articles I can find.

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

Netherlands22664 Posts

September 07 2017 22:31 GMT

#13322

The speed of the particles depends on the power/intensity of the flare and probably some other stuff.
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

September 08 2017 01:35 GMT

#13323

Information available at www.swpc.noaa.gov

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

Denmark4783 Posts

September 08 2017 01:45 GMT

#13324

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?

Oshuy

Netherlands529 Posts

September 08 2017 02:04 GMT

#13325

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

September 10 2017 03:37 GMT

#13326

Where is teamliquid IRC channel? I used to sometimes scroll down teamliquid web site and click the irc channel to join discussions about dota or starcraft or teamliquid relevant discussions. I liked this and I preferred irc for instant chatting over the forums becuase forums and deditated to subjects and are not instant.

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 States7393 Posts

September 11 2017 00:29 GMT

#13327

Im sick and experiencing excessive saliva production, my mouth fills up in like 1 - 3 minutes and it makes doing anything really hard because I have to get up and spit out a full mouth of saliva every couple of minutes.

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

Belgium5232 Posts

September 11 2017 00:41 GMT

#13328

Have you tried swallowing?

Zambrah

United States7393 Posts

September 11 2017 00:42 GMT

#13329

On September 11 2017 09:41 Uldridge wrote:
Have you tried swallowing?

Makes me nauseated

JimmiC

Canada22817 Posts

September 11 2017 00:43 GMT

#13330

--- Nuked ---

Epishade

United States2267 Posts

September 11 2017 01:59 GMT

#13331

Sleep with a bucket under your head and see how much you collect during the night. If it's over 2 cups, you have enough to perform the Slopanski Ritual by drawing out a hexagram with your collected saliva and sacrificing a small rodent (can't be over 1 lb) in the middle. This should preferably be done with the blinds closed and when the sun is at the highest point in the sky (around noon). This ensures that Helios is most likely to answer your call and grant you your three wishes, one of which you can use to cure your excessive saliva production.

Ghostcom

Denmark4783 Posts

September 11 2017 11:53 GMT

#13332

Throw up.

AbouSV

Germany1278 Posts

September 11 2017 12:29 GMT

#13333

Rinse your mouth with clear water, then eat one or two salty chips.

GreenHorizons

United States24391 Posts

September 11 2017 20:12 GMT

#13334

So I was at a bar with some Bandido support members (Amigos) and I couldn't help but wonder about the irony of the white supremacy tattoos and the name of the ~~gang~~ motorcycle club they serve being a tribute to Mexican outlaws.

Like what's that about?

JimmiC

Canada22817 Posts

September 11 2017 20:27 GMT

#13335

--- Nuked ---

heyitsMiro

83 Posts

September 12 2017 09:54 GMT

#13336

Does "just before midnight on Thursday" mean 11:59pm wednesday night or 11:59 pm thursday night?

Simberto

Germany12037 Posts

September 12 2017 10:04 GMT

#13337

Thursday night imo. Midnight is something you stay up for, not something you get up early, for and thus it belongs to the previous day. The next day begins when you get up in the morning.

Artisreal

Germany9235 Posts

September 12 2017 10:14 GMT

#13338

Sacrifice two goats, just to be sure.

Navane

Netherlands2762 Posts

September 12 2017 10:29 GMT

#13339

(Just before)(midnight on thursday) is ambiguous because (midnight on thursday) is ambiguous.

(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.