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mikeg64
2011-Feb-21, 12:58 PM
With the recent solar activity
e.g. See SDO pick of the week feb 17th 2011 (http://sdo.gsfc.nasa.gov/gallery/potw.php?v=item&id=42)

I have heard stories that the aurora will be observable latitudes which are far from the poles. After hearing this rumour I took a look at the space weather auroral activity chart.
( see Auroral Activity Extrapolated from NOAA POES (http://www.swpc.noaa.gov/pmap/index.html) ).

These charts show that auroral oval extends far beyond the poles and for my location in the middle of England there is a mesurable degree of energetic particles. Under what sort of conditions could aurora be observed from my location (close to the edge of the auroral ) could the aurora be observed?

The NOAA/POES website provides good guidelines for viewing the aurora butas solar cycle 24 progresses what tips can people recommend for observing the aurora?

By the way its cloudy here:boohoo:!

Swift
2011-Feb-21, 01:38 PM
This webpage from NOAA (http://www.swpc.noaa.gov/Aurora/) gives a good explanation of the relationship among latitude, the strength of the geomagnetic activity (measured by something called Kp) and your chance of seeing an aurora.

Once you know your magnetic latitude, and how high the Kp index needs to be for you to see the aurora at your magnetic latitude, it comes down to choosing a viewing time of high magnetic activity by frequently checking the Kp index and SWPC forecast. It could also be worthwhile to check the POES Auroral Activity page, which might or might not be more up-to-date than the Kp, depending on the time of the most recent polar pass of the POES satellite. (The table below will help you relate the POES Auroral Activity Level to the Kp index.) Of course, for you to see the aurora it will also have to be a clear night without interference from city lights or moonlight.

If you solve the cloud problem, please, let the rest of us know the solution. ;)

mikeg64
2011-Feb-21, 03:00 PM
Looking at the Kp maps of midnight equatorward boundaries (e.g. for Eurasia (http://www.swpc.noaa.gov/Aurora/globeNE.html)). It shows that in our areathe Kp values are around 9 this is high so we can expect to see aurora, on a cloudless, moonless night away from bright city/town lights. Is the magnetic activity measured here a measure of the interaction between energgetic particles and the earths magnetic field... afterall that is what we are ultimately looking for, cheers.

Swift
2011-Feb-21, 03:07 PM
I don't know where on the Earth you are, but if you are some where near the Kp = 9 line on that map, then the Kp would have to be that high or higher for you to see an aurora. Kp = 9 is very high, so it would require a big event for that to happen.

mikeg64
2011-Feb-21, 07:47 PM
I was beginning to assume that I was interpreting the NOAA data correctly but now I'm unsure.

Looking at the chart
http://www.swpc.noaa.gov/Aurora/globeNE.html
I'm located in the UK between the yellow line Kp=7 and the red line Kp=9. Seems to go higher as you move south, that doesn't make sense to me!

Also once you have decided if it is worthwhile looking for the aurora how do you determine the best direction for observation?


If you solve the cloud problem, please, let the rest of us know the solution.

Seems that the best plan of action might be to view above the clouds how about this solution?
How to film the earth from space! (http://www.shef.ac.uk/mediacentre/2011/1834-video-earth-edge-space.html)

Swift
2011-Feb-21, 07:58 PM
I was beginning to assume that I was interpreting the NOAA data correctly but now I'm unsure.

Looking at the chart
http://www.swpc.noaa.gov/Aurora/globeNE.html
I'm located in the UK between the yellow line Kp=7 and the red line Kp=9. Seems to go higher as you move south, that doesn't make sense to me!
The Kp reading is how big/energetic the aurora creating event is. So, some small little event, is going to have a small Kp, like 2 or 3, and would only be visible if you are very close to the North Pole. Some huge storm-of-the-century event might have a Kp of 9 or 10, and will be visible much further away from the pole. The Kp lines on the map indicate how big the Kp of the event has to be in order for a person at that location to see it. If you are between 7 and 9, you would need an event with a Kp of like 8 or 9 or higher for you to see it at your location.


Also once you have decided if it is worthwhile looking for the aurora how do you determine the best direction for observation?
It is almost universally to the North, unless you are very close to the North Pole. The one time I saw them in Alaska, they covered the sky from almost directly overhead to the Northern horizon. The one time I saw them in Ohio (that was a Kp ~9 event), they were just barely visible over the Northern horizon.

Oh, and for those of you listening at home from the Southern hemisphere, this is all still true, except substitute South for North.

mikeg64
2011-Feb-21, 08:36 PM
OK nice one thanks for the explanation so the rumours I heard were unreliable!
So what I do is this check http://www.swpc.noaa.gov/rt_plots/kp_3d.html for the current Kp index for an event.

Check this against http://www.swpc.noaa.gov/Aurora/globeNE.html, then I know how far North I need to travel....

Well, I always planned on taking a trip to Scotland for an aurora watch!
Thanks

Swift
2011-Feb-21, 09:35 PM
I'm sure there are other things to do in Scotland while you are there. :D

For those of us interested in such things (and you are not the only one), another great website is spaceweather.com (http://www.spaceweather.com/). It has lots of info about the current state of the sun, measures of Kp, CME and solar flare events, etc. And if you can't see the auroras themselves, there is a nice photo gallery of people who are closer to the action and snap pictures.

Jens
2011-Feb-22, 05:13 AM
If you solve the cloud problem, please, let the rest of us know the solution. ;)

A very tall ladder?

mikeg64
2011-Feb-22, 01:07 PM
or perhaps a space elevator

Ivan Viehoff
2011-Feb-24, 11:56 AM
My grandfather once saw the aurora at Sheringham in Norfolk. But there was a lot less light pollution in those days, and being on north-facing coast helped. I understand that the aurora have on occasion been seen as far south as the Caribbean, but the latitude at which you can see the aurora depends upon your longitude, as the aurora form an oval shape, and are not exactly centred on the north pole.

Clear skies seem to be are quite uncommon in England. Although the sky can appear to be clear during the day, when the sun goes down it can become apparent that there is a light layer of altocirrus that allows you to see the moon and a handful of planets/stars, but not much else. A friend of mine who used to do a lot of practical astronomical observation at Keele (outside Stoke) reckoned he could get useful observation about 1 night in 5 during the observing season.