I was looking at that spectacular picture of a solar eclipse seen from space, and for some reason I suddenly wondered whether eclipses are ever seen when the sun rises or sets. After thinking about it for a while I realized to my shame that I couldn't come up with a definitive answer, so I decided to rush to the BA forum and settle the matter [img]/phpBB/images/smiles/icon_smile.gif[/img] I personally can't recall ever hearing or reading about the sun rising or setting in an eclipse, and whenever there is a solar eclipse somewhere it seems it always happens during the daytime. If what I'm suggesting is possible and does indeed happen, is there any place where I might find information on where and when it has happened in the past, possibly with pictures? It must be pretty eery seeing a black sun rising above the horizon at dawn [img]/phpBB/images/smiles/icon_eek.gif[/img]

Sure it can happen and does.

Although it will never be at greatest totality, since that is defined as the time when the sun, moon and earth are in a perfect line. Greatest totality will be at the local noon, not ever at sunrise/sunset.

Here are some pictures of anular/total eclispses at dawn/dusk:

<ul>[*]Annular Eclipse: The Ring of Fire[*]A Crescent Sunrise[*]Eclipse Over The Mountain[/list]

It looks like the Total Solar Eclipse of 2002 December 04 will start with a total eclipse at sunrise, just east of Africa, and end with a total eclipse at sunset, in Australia.

Greatest totality is just greatest eclipse, isn't it? That website says that the local circumstances at greatest eclipse have the Sun at an azimuth of 15 degrees. That would be quite off from local noon.

There is always a point of totality, which is the point behind the Moon directly opposite the Sun. It's just a question of whether the Earth is at that point or not. Since the Sun, Moon, and Earth are always shifting position with each other, it appears that the point of totality is constantly shifting to the east (as the Moon moves from west to east), while at the same time the Earth is moving towards the west (in it's path around the Sun). The effects combine to cause the umbra to trace a path across the Earth's surface from west to east.

From Grapes' link:

http://sunearth.gsfc.nasa.gov/eclips...ec_animate.GIF

http://sunearth.gsfc.nasa.gov/eclips...02animate.html

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<font size="-1">PLEASE NOTE: Some quantum physics theories suggest that when the consumer is not directly observing this product, it may cease to exist or will exist only in a vague and undetermined state.</font>

<font size="-1">(A couple of minor changes)</font>

<font size=-1>[ This Message was edited by: David Hall on 2002-10-07 01:45 ]</font>

Yes, Greatest Eclipse is the phrase I wanted, not greatest totality. My error.

However, the reason why the Azimuth of the sun is not 0 degrees (due North, since this eclipse is in the southern hemisphere) defining the meridian and therefore local noon, I don't know.

Because totality occurs not when the Earth, moon and Sun are in a line, but when the observer, moon and Sun are in a line. Totality can occur at sunrise or sunset. In the case later this year, it does both. The greatest totality should occur roughly at noon, but the lunar path across the Sun might change that--the orbits are not all lined up. An eclipse near the poles is even worse.

In a solar eclipse, the point of totality sweeps right across the surface of the Earth, crossing multiple time zones in a matter of just a couple of hours. If you're standing somewhere on this line, then you'll see the eclipse.

Look at the animation I posted. Try to imagine yourself as being the Moon. You're looking at your own shadow when suddenly the Earth waltzes right through it. Your shadow runs right across the face of it, starting at the point where it's sunrise, cruising past the noontime meridian, and finally slipping off the Earth's fat body somewhere around the sunset terminator.

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere

BTW Amstrad, the last link you gave is a lunar eclipse. [img]/phpBB/images/smiles/icon_smile.gif[/img]

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere

Yeah, why don't any of these amazing solar eclipses occur in the middle of the night? [img]/phpBB/images/smiles/icon_wink.gif[/img] [img]/phpBB/images/smiles/icon_biggrin.gif[/img]

(I'm sure you really meant to say "in the middle of the day", but I just couldn't pass this one up. [img]/phpBB/images/smiles/icon_smile.gif[/img])

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere

My wife and I were on a cruise, in large part to see the solar eclipse in the Caribbean in 1998 (?). She was asked at one point when the eclipse was going to happen and replied, "About two o'clock tomorrow." She was then asked, "morning or afternoon?" [img]/phpBB/images/smiles/icon_wink.gif[/img]

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David,
Cool animation! [img]/phpBB/images/smiles/icon_biggrin.gif[/img]

A couple of clarifications for those who might not be aware:
1) The large gray area is the penumbral eclipse and would (in reality) shade from full daylight at the edge to dark at the center.
2) Totality is represented by the little black dot at the center.

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Thanks guys, once again I've gained a little wisdom thanks to this forum [img]/phpBB/images/smiles/icon_smile.gif[/img] (And yes, I did indeed intend for 'during the daytime' to be interpreted as 'in the middle of the day', and not the way it sounded. Thanks a lot for making me look silly [img]/phpBB/images/smiles/icon_wink.gif[/img])

I second that. And, thanks for the explanation Kaptain. I didn't see the dot until you pointed it out. [img]/phpBB/images/smiles/icon_smile.gif[/img]

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Hey, that's what we're here for. [img]/phpBB/images/smiles/icon_biggrin.gif[/img]

Don't thank me. Or rather give some credit also to GrapesOfWrath, who provided the original link. All I did was post the graphic here. [img]/phpBB/images/smiles/icon_smile.gif[/img]

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...And that, my liege, is how we know the Earth to be banana-shaped. --Sir Bedevere