Quote:
Originally Posted by mithrandir
See OzEclipse Joe's link to his web page a few posts back. He recommends the southern limit for this (and maybe all) annular eclipses.
That is a bit south of Tennant Creek so you might not even have to drive out of town.
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I must apologize, I made an error when I referred to the southern limit in my post. Both limits give this effect but I said southern limit because the southern lunar limb is more mountainous than the northern lunar limb resulting in brighter beads. However, southern limb and southern limit are two different things.
Here's a brain twister - and I hope I finally have this right way round........
On the sth limit on Earth you are seeing the nth lunar limb mountains graze the edge of the suns disk. North lunar limb mountains are smaller than the sth lunar limb mountains and hence produce beads that are not quite as bright. The brightness is also a function of how close you are to the limit zone - ie how much photosphere is visible. So the north limit (southern lunar limb) produces a better bead display than south limit(northern lunar limb). Both however produce a more interesting show than the center line.
Your observing site should be near but not on the limit. Because of the lunar limb, the limit is a band not a line. Dan shows results from varying distances inside the limits in his talk.
It's in two parts. I only listed the first part in my original post - I have edited that post.
http://tinyurl.com/btuy358 PART 1 [17mins]
http://tinyurl.com/coz9usu PART 2 [11 mins]
The idea is that you are in a position where the Baily Beads fire off tracing an arc around the limb. Of course you won't see the symmetrical annulus. In my post I linked to Dan Fisher's talk at the last international solar eclipse conference. It's a 28min video but explains it quite well.
For those of you still euphoric about last years total, don't believe for a second that a 94% annular is 94% of a total eclipse. It's a very different event.
Cyclone, you only need to drive about 80km north of Lakeland to get to the southern limit. So if the road conditions are suitable to get there, you'll only be an hour or so from the sealed road to get back. Being a local, you should be able to tell if rain's coming and hi-tail it back to tarmac.
If you check out my web page, you'll note that weather prospects on the east coast are not the best but if I lived in Mareeba I'd probably head to that spot on the development road north of Lakeland too.
Tennant Ck is likewise near the sth limit. You can go to the north limit but it will mean sleeping out or driving several hundred km in the dark. As I found out last year, that has its hazards. I hit an animal while night driving on my way to Cairns.
So choosing where to go is not as simple as heading for the longest duration on the center line. If you have accommodation in Tennant Creek, I'd recommend you head just a short way south but stay inside the limit a good distance.
In Newman, we're already near the north limit so that's probably the area where I'll stay. The only thing that might push me south is that the highway at the south limit is much closer to the end of the path of annularity - sun lower to the horizon.
I've added a table of contact times for Australian locations to my web page.
http://www.joe-cali.com/eclipses/PLA...013/index.html
Joe