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Star Trail and Aurora

PostPosted: Sat Dec 16, 2006 10:38 am
by thelastname
Went out to try to see some auroras, it looks like the camera managed to pick up the pink glow while i was doing a star trail. C&C welcome.

Image

The orange glow down the bottom is Portfairy and Warrnambool to the left.

PostPosted: Sat Dec 16, 2006 10:45 am
by Yi-P
Cool star trails, but I thought you only get Aurora effects on the far Northern Hemisphere of the Earth.... :roll:

PostPosted: Sat Dec 16, 2006 11:28 am
by daniel_r
Yi-P wrote:Cool star trails, but I thought you only get Aurora effects on the far Northern Hemisphere of the Earth.... :roll:


Yi-P, I'm sure you'll get a more detailed answer from some of the more astronomically inclined here, but there's indeed Aurora that can be seen from the southern hemisphere. It's referred to as Aurora Australis (southern lights) where the nothern hemisphere occurance is referred to as Aurora Borealis

This Wikipedia Article has some good coverage of the topic.

The Aurora effects are common during periods of peak solar flare/storm activity. There's been increased solar storm activity over the last week, as reported here. Earlier this week, the current Shuttle Mission (STS-116) was was affected by the solar flare activity.

This ain't my area of expertise though... :lol:

PostPosted: Sat Dec 16, 2006 2:51 pm
by Big V
We do get them and there was one last night and there is a chance of another tonight. If you want to photograph them, it is bettert to stick to a shorter exposure of say 30 sec, this improves the contrast and the stars do not trail..
here is one taken with a canon g2 point and shoot, 15 sec 400 ISO f2.8
Image
tonight I shall use my canon 30d, so am expecting far better results..

PostPosted: Sat Dec 16, 2006 4:55 pm
by Gordon
Yi-P wrote:Cool star trails, but I thought you only get Aurora effects on the far Northern Hemisphere of the Earth.... :roll:


The southern aurora, Aurora Australis, is basically a mirror of the Aurora Borealis. The Northern version is seen a lot more often because a lot of people live in the far north areas (say north of 45N)- much of Europe and Russia, and all of Alaska, Canada and Northern USA. Very few people live in Patagonia or NZ at similar southern latitudes!
However, when the sun is active and throwing off a lot of energetic particles in Coronal Mass Ejections (CME) the auroral oval (it's a ring right around the poles) extends further away from the poles and can be seen at lower latitudes. I didn't see anything last night from 31S, (although I didn't stay up all night looking either, just checking occasionally) but have seen plenty of displays in the past, and posted pics on my web page. Most people in Australia choose to live in cities and wont have a chance to see any except the very brightest displays. You really do need a reasonably dark sky to have a chance of seeing them at low latitudes. They have been seen from as far north as Central Queensland during big displays.

PostPosted: Sat Dec 16, 2006 5:50 pm
by thelastname
Here is the forecast chart for the next 3 hours, it's best that it's up above 8 for Australia.
http://www.sec.noaa.gov/rt_plots/kp_3d.html

And this chart is more of current activity. On the left it has activity level, need to be at least 8 or better.
http://www.sec.noaa.gov/pmap/pmapS.html

These charts are an indication only, there are no guarantees. Some times aurora activity can be strong and see nothing, and it also can be weak and you can see plenty.

The shot was taken as an intention of taking a star trail, when I got home and put it on the computer I noticed the very faint aurora. At the time I did not see the aurora.

PostPosted: Sat Dec 16, 2006 10:17 pm
by BBJ
Nice shot that, and yeh well i was over at Warrnambool last tuesday as do go over there from time to time. I must get out oneday and try some of these longer exposures.