AURORA ALERT

astrofud

OK Folks

These are not aurorae because-
Solar activity is low and the Sun is the ONLY thing that causes them.
Aurorae CANNOT be seen through clouds unless the clouds are very thin (cirrus) and the display is huge. Such a display has not happened in Ireland since 1859.
Tonight IS NOT a moonless night. The Moon rose about 21:30 and is just past full. Moonglow WILL light up clouds.
Most auroral displays from Ireland appear as a faint diffuse glow hugging the northern horizon and are usually masked by light pollution.
Geoeffective (directed at earth) coronal mass ejections or a fast solar wind cause aurorae. Neither have occured this week. There was an increase in solar wind speed a few days ago but this was not strong enough to spark a low latitude display.
Solar flares DO NOT cause aurorae.
My solar blog http://astrofud.wordpress.comwill give alerts for display over Ireland. I use data from my own solar observatory compared with satelite data and magnetometers from similar latitudes. This method has proved sucsessful for previous displays in 2011.


Dave Gradwell

MoonDancer

The sky wasn't completely cloudy last night with what I saw. I just can't think of anything else it could be, This was a vibrant green- there is country side behind my house and you could see it high enough in the sky and going behind the Mountain to make the outline of the Mountain very prominent. I had a friend tell me today that they saw a swirly green strip in the sky too.

astrofud

Auroral displays dont just suddenly appear. They are the result of solar events that happen days previously. As a result they are predicable. No events occured on the Sun this week that would have induced a display as described here. I dont doubt that something was observed but they werent aurora boreallis.

JeffK88

Perhaps this then because the sky was green hard to make out in them pics . This article mentions severe weather im not saying there is tornadoes but some kind of weather system

http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-if-sky-is-green-run-for-cover-tornado-is-coming

MoonDancer

JeffK88 wrote: »

Perhaps this then because the sky was green hard to make out in them pics . This article mentions severe weather im not saying there is tornadoes but some kind of weather system

http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-if-sky-is-green-run-for-cover-tornado-is-coming

Thats interesting, because the kids and I noticed a funnel shaped cloud at the same time. Now it wasn't a tornado and it didn't rotate, but just that it looked like one.

WindSock

http://www.thejournal.ie/northern-lights-could-be-seen-over-ireland-tonight-354528-Feb2012/

Supposed to be a good batch of it on tonight.

Anyone any idea what might be the best time and location in Dublin to have a look?

Iancar29

WindSock wrote: »

http://www.thejournal.ie/northern-lights-could-be-seen-over-ireland-tonight-354528-Feb2012/

Supposed to be a good batch of it on tonight.

Anyone any idea what might be the best time and location in Dublin to have a look?

Chances of seeing them in DUblin is slim to nill pal! ... im in dublin myself. We'd want to be up north!

For dublin to have a latitude we'd need a kp of 8 or so. Which is unlikely with this CME.

But if u STILL want to go out then up high and away from the lights... i would usually go out the backroads of swords, st magarets area.

astrofud

The alert David Moore refers to is for high latitude (polar regions) of the Earth only. The CME in question is weak and MAY only hit us a glancing blow. Geomagnetic activity remains normal over Ireland as such chances for auroral activity are low.

Dave Gradwell
http://astrofud.wordpress.com
www.davegradwell.com

astrofud

For dublin to have a latitude we'd need a kp of 8 or so

Iancar29 what do you mean by the above?

Iancar29

astrofud wrote: »

Iancar29 what do you mean by the above?

woops.... For Dublin to see the lights we'd need the energy level of the impact to be at kp 8 ( severe storm ) And real clear skies ha

astrofud

Magnetic activity tonight, there may be a small window of auroral activity, see my blog http://astrofud.wordpress.com

Dave Gradwell

astrofud

Some more activity in the early hours, did anyone see anything? my blog has more details http://astrofud.wordpress.com

MoonDancer

astrofud wrote: »

Some more activity in the early hours, did anyone see anything? my blog has more details http://astrofud.wordpress.com

Nope didn't see anything unfortunately.
The more I think about the last night I saw green in the sky, it must have been some sort of electrical storm and not the aurora, obviously because of the evidence in solar activity.

This is why I like coming onto this forum, because there are a lot of well educated people here to answer any queries.

astrofud

No prob Moondancer. The most important thing is to observe and question, thats how we learn.

DaveG

muckish

astrofud wrote: »

Some more activity in the early hours, did anyone see anything? my blog has more details http://astrofud.wordpress.com

Dave,

what's your magnetometer setup like and have you it linked to a data logger. Could you publish results live on a website etc.. Is this something any Joe Soap could do? Any advice?

astrofud

Hi Mucklish

My setup is a small extremely strong rare earth magnet suspended between a nulling magnetic field made of four other magnets. The nulling magnetic field cancels out the Earths magnetic field which allows me to measure the interplanetary magnetic field (imf is the suns magnetic field in space). Unfortunately it also leaves the magnet open to local magnetic fields such as passing cars, washing machines and even the freezer door being opened! The rare earth magnet tilts in proportion to the IMF. The tilt is logged by software to produce the graphs seen on my solar blog.

TBH it's not something I'd get into unless you are willing to put a lot (and I mean a lot) of time into it. It has taken me over 2 years to get to the stage where my data is reliable enough to publish. It requires logging data over a year to have a measure of normal activity. You then need to be able to recognise solar activty vs local activity. Then callibrate to see what flucuations can cause local aurorae.

The odd time we get fluctuaions in Ireland I publish on my solar blog, which usually gives enough time for people to check the skies. I have been sucsessful with predicting most displays with this method. I am very careful about publishing as too many false alarms and your data cant be trusted. I am currently building a different type of electronic magnetometer which I hope to stream to my website.

TBH geomagnetometry is a bit of a black art. Look at this last display, we still dont know what caused it, there were no CMEs or strong solar winds. The Kp index, (which I DO NOT reccommend as an indicator for Ireland) was at level 2 when my magnetomter spiked, not a value you would expect. I have seen Kp values of 6 with no magnetic activity over Ireland.

HTH

BTW I give popular level talks on all things Sun if you have a group thats interested.

muckish

astrofud wrote: »

Hi Mucklish

My setup is a small extremely strong rare earth magnet suspended between a nulling magnetic field made of four other magnets. The nulling magnetic field cancels out the Earths magnetic field which allows me to measure the interplanetary magnetic field (imf is the suns magnetic field in space). Unfortunately it also leaves the magnet open to local magnetic fields such as passing cars, washing machines and even the freezer door being opened! The rare earth magnet tilts in proportion to the IMF. The tilt is logged by software to produce the graphs seen on my solar blog.

TBH it's not something I'd get into unless you are willing to put a lot (and I mean a lot) of time into it. It has taken me over 2 years to get to the stage where my data is reliable enough to publish. It requires logging data over a year to have a measure of normal activity. You then need to be able to recognise solar activty vs local activity. Then callibrate to see what flucuations can cause local aurorae.

The odd time we get fluctuaions in Ireland I publish on my solar blog, which usually gives enough time for people to check the skies. I have been sucsessful with predicting most displays with this method. I am very careful about publishing as too many false alarms and your data cant be trusted. I am currently building a different type of electronic magnetometer which I hope to stream to my website.

TBH geomagnetometry is a bit of a black art. Look at this last display, we still dont know what caused it, there were no CMEs or strong solar winds. The Kp index, (which I DO NOT reccommend as an indicator for Ireland) was at level 2 when my magnetomter spiked, not a value you would expect. I have seen Kp values of 6 with no magnetic activity over Ireland.

HTH

BTW I give popular level talks on all things Sun if you have a group thats interested.

Cheers Dave,
I was looking at these sensors and just wondering http://www.speakesensors.co.uk/
The Magnetometer from Kiruna was amazing to watch over the last 2 days in comparison to the KP index. The strong southerly IMF seems to have played the biggest role in the aurorae of the last 2 days. I'm guessing the direction of the IMF is partly one of the reasons that a KP6 mightn't perform over Ireland? From the data that is available on various websites, what would you recommend looking out for to indicate the potential of an aurora over Ireland.

astrofud

I was looking at these sensors and just wondering http://www.speakesensors.co.uk/

Yes they are good fluxgate magnetometers. You need to build a circuit around it, and an A to D converter. They must be buried about 4 feet into the ground as they are temp sensitive aswell. Then collect data as I describe above to callibrate it.

The strong southerly IMF seems to have played the biggest role in the aurorae of the last 2 days. I'm guessing the direction of the IMF is partly one of the reasons that a KP6 mightn't perform over Ireland?

The south polarity is needed to connect with our magnetic field which has a north polarity at the IMF/magnetosphere boundry. In the same way if you want magnets to connect they have opposite poles facing each other. But it was the disturbance on the 14th that started it and this we have no explanation for. If you like, the event on the 14th caused a rip, then the IMF flipped polarity allowing solar wind particles to be pulled through the rip. Kp is just just a measurement of the effect. The reason I havent found it accurate is that the aurorae are non homogeneous (not the same everywhere). This last event proves it well but normally it works the other way round, the Kp shows high and local magnetic activity is low.

From the data that is available on various websites, what would you recommend looking out for to indicate the potential of an aurora over Ireland

NASA's space weather is good
keep watching your swedish magnetometer
my magnetometer data, being local, is the best indicator for ireland, so keep an eye on my blog. My observatory also picks up solar flares so if theres a CME associated it will give a few days notice.

HTH

De_Lady_Lacey

Hi Guys/Gals

Im just back from Tromso and had a wonderful 3 nights with the Lady of the night skies, It was amazing. Have to say a big thank you for all the great advise on this topic, you are very generous with your education of this phenomena.
I was lucky enough to photograph her too which was my most proudest moment.
BUT, Im not finished with her yet.... nope!!.... she's in my veins now. More addicted than ever now. I wanna catch her in my own country so if she is coming to Ireland's north...... im in for the wait. If ye are pooling together to go up north let me know. Thanks

refusetolose

Chris Hadfield posted this on twitter along with this message

Northern Lights - recent aurora in green and red waves, USA and Canada below, the universe above