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John Kierein
2001-Dec-12, 04:13 PM
Where should I look to find when Friday's partial solar eclipse will be visible from various locations? Anybody know? Is this the official end of Ramadan?

SeanF
2001-Dec-12, 04:18 PM
Try here. (http://sunearth.gsfc.nasa.gov/eclipse/ASE2001/ASE2001.html)

I've got my solar filter ready for my telescope -- it dang well better not be cloudy Friday afternoon!

David Hall
2001-Dec-12, 04:34 PM
Hmm. Doesn't look too impressive for North American viewers. Only those in Florida get anything like a heavy eclipse. Not that it matters to me one way or the other. /phpBB/images/smiles/icon_razz.gif

So, what's it like to view an eclipse through a filtered telescope? I've never been able to see one except through projection methods.

Back in 1994 I drove 2 hours to view the annular eclipse in Oklahoma City. It was quite cool. I used my binoculars to project dual images onto cardboard and showed it off to passersby. I've never had a chance yet to see a total eclipse, but at least I have the pleasure of knowing I've seen an event just as rare (or moreso?), and even more unusual, if not quite as dramatic.

John Kierein
2001-Dec-12, 04:41 PM
cool, thanx.

ToSeek
2001-Dec-12, 05:06 PM
On 2001-12-12 11:13, John Kierein wrote:
Where should I look to find when Friday's partial solar eclipse will be visible from various locations? Anybody know? Is this the official end of Ramadan?


Islamic months begin with the sighting of the new moon, so I would think this would qualify.

GrapesOfWrath
2001-Dec-12, 05:13 PM
I think they have to see the crescent, no?

SeanF
2001-Dec-12, 05:23 PM
On 2001-12-12 11:34, David Hall wrote:
Hmm. Doesn't look too impressive for North American viewers. Only those in Florida get anything like a heavy eclipse. Not that it matters to me one way or the other. /phpBB/images/smiles/icon_razz.gif


Nope, and I'm far enough north that I'm only going to get about 13% of the sun covered -- still worth looking at, I think.

I'm now patiently waiting for August 21, 2017 . . . total eclipse visible throughout most of the continental US! Woo-hoo! And less than 16 years away! /phpBB/images/smiles/icon_wink.gif



So, what's it like to view an eclipse through a filtered telescope? I've never been able to see one except through projection methods.


I don't know yet, I'll let you know after this weekend (weather permitting). I just got my 'scope this past summer, and just got the solar filter a couple of weeks ago. I've checked out the sun through it already. I expect the eclipse to look much like a binocular projection, a white disk with a little bite taken out of it, but through the 'scope one can see sunspots and the like as well.



Back in 1994 I drove 2 hours to view the annular eclipse in Oklahoma City. It was quite cool. I used my binoculars to project dual images onto cardboard and showed it off to passersby. I've never had a chance yet to see a total eclipse, but at least I have the pleasure of knowing I've seen an event just as rare (or moreso?), and even more unusual, if not quite as dramatic.


This eclipse is actually an annular eclipse rather than total as well. I'm not sure which is actually more common, if either is.

I've now found myself wondering if, through a filtered 'scope, it would be possible to observe the shadow of the space station transiting the sun if its orbit ever happens to line up correctly . . . that would be pretty cool. /phpBB/images/smiles/icon_smile.gif


_________________
SeanF

<font size=-1>[ This Message was edited by: SeanF on 2001-12-12 12:24 ]</font>

David Hall
2001-Dec-12, 05:52 PM
On 2001-12-12 12:23, SeanF wrote:

This eclipse is actually an annular eclipse rather than total as well. I'm not sure which is actually more common, if either is.


I noticed. That's what brought back the memory.

I'm thinking now that an annular eclipse would actually be slightly less common than a total one. annular eclipses can only happen when the Moon is far enough out in it's orbit that it appears smaller than the sun, which I guess would only happen when it's near apogee. A small percentage of it's orbit. A total eclipse would happen whenever the Moon appeared large enough to cover the face of the Sun, which could be 'just barely' or 'quite a lot', which I think would occur over a greater part of the orbit. But I suppose it depends on how they generally line up to begin with.



I've now found myself wondering if, through a filtered 'scope, it would be possible to observe the shadow of the space station transiting the sun if its orbit ever happens to line up correctly . . . that would be pretty cool. /phpBB/images/smiles/icon_smile.gif


I agree. That would be pretty cool.

Oh for a good telescope with all the fixins'. Even in the heart of the city I'm sure I'd be able to see some nice sights (Jupiter and Saturn are nice & bright now, and the Orion Nebula is beckoning../phpBB/images/smiles/icon_smile.gif)

_________________
David Hall
"Dave... my mind is going... I can feel it... I can feel it." (http://www.occn.zaq.ne.jp/cuaea503/whatnots/2001_feel_it.wav)

<font size=-1>(Fixed a broken quote)</font>

<font size=-1>[ This Message was edited by: David Hall on 2001-12-12 12:54 ]</font>

Hale_Bopp
2001-Dec-12, 06:06 PM
Actually, the 2017 eclipse will only be total for a very small portion of the U.S. The path of totality is very narrow...say 100 miles or less (I don't know the exact mas size off the top of my head. However, the width of the path of totality does vary from eclipse to eclipse).

You can bet that I will be taking planes, trains or automobiles to try and get in that path!

I have seen a total solar eclipse...the '99 one in Germany. Yes, there were a couple of VERY small holes in the clouds and I wasn't sure I was going to get to see it at all in spite of driving for hours to find a clear spot. In fact, it was cloudy at the start of totality and broke a few seconds after the first diamond ring! I saw most of totality and the second diamond ring. Lots of prominences were visible as well.

Rob

ToSeek
2001-Dec-12, 07:02 PM
On 2001-12-12 12:23, SeanF wrote:

This eclipse is actually an annular eclipse rather than total as well. I'm not sure which is actually more common, if either is.


This list (http://www.geocities.com/CapeCanaveral/7137/sol0899/futureeclipse.html) of eclipses from 1991 to 2020 is about evenly divided between annular and total (21 and 20, respectively, by my count).

SeanF
2001-Dec-12, 09:13 PM
On 2001-12-12 13:06, Hale_Bopp wrote:
Actually, the 2017 eclipse will only be total for a very small portion of the U.S. The path of totality is very narrow...say 100 miles or less (I don't know the exact mas size off the top of my head. However, the width of the path of totality does vary from eclipse to eclipse).


I knew when I typed that that I should've been more clear. Yes, the path of totality cuts a narrow swath across the lower 48, but the eclipse itself (which is "total" as opposed to "annular") will be visible, I believe, through the entire 48 states, in fact most of North America . . .



You can bet that I will be taking planes, trains or automobiles to try and get in that path!


Me, too! I wonder how far ahead of time hotels start taking reservations . . .



I have seen a total solar eclipse...the '99 one in Germany. Yes, there were a couple of VERY small holes in the clouds and I wasn't sure I was going to get to see it at all in spite of driving for hours to find a clear spot. In fact, it was cloudy at the start of totality and broke a few seconds after the first diamond ring! I saw most of totality and the second diamond ring. Lots of prominences were visible as well.

Rob


I am jealous! /phpBB/images/smiles/icon_smile.gif

Kaptain K
2001-Dec-12, 09:32 PM
According to the list linked above, the path of totality will be 115 miles wide and totality will last 2 minutes and 40 seconds.

GrapesOfWrath
2001-Dec-13, 03:29 PM
On 2001-12-12 14:02, ToSeek wrote:
This list (http://www.geocities.com/CapeCanaveral/7137/sol0899/futureeclipse.html) of eclipses from 1991 to 2020 is about evenly divided between annular and total (21 and 20, respectively, by my count).
According to Planetscapes (http://www.planetscapes.com/solar/eng/homepage.htm) information, the ratio of the sun size to the mean distance of the earth to the sun (viewed at noon) is a bit (1.1%) larger than the lunar ratio. And the lunar eccentricity is over three times larger than the earth eccentricity, and would have more effect on the relative sizes--the moon would spend more time farther out. And viewing the eclipse at hours other than noon would tend to make the moon relatively smaller. So, I guess we'd expect slightly more annular eclipses.

Tomorrow, according to figures from SkyMap, the Sun will be about 4.7% bigger than the moon, in angular diameter, viewed from Florida.