SE Newsletter March 1999

Diamond Ring

From: Bob Morris morris@sce.carleton.ca To: Solar Eclipse solareclipses@AULA.COM Subject: [SE] Diamond rings! Date: Monday, February 01, 1999 1:45 PM

The diamond ring at 3rd contact at Aruba was the most impressive sight I have ever seen! In fact, I now would term this sight as more spectacular than the totally eclipsed sun, something I would have not done before, based upon my experience in Quebec in '63 and Virginia in '70.

Reading newspaper accounts of what was seen in 1925 in New York City leads me to believe that they had a similarly impressive show, and that such an impressive diamond ring is rare:

"It made a deeper impression on New York crowds than any other feature of the heavenly show. The incomparable beauty of this sight, unexpected by most of the watchers, could not do otherwise than make such an impression and the effect was intensified by the fact that every observer felt the thrill of discovery. The advance accounts had contained no notice that the eclipse had ornaments of this brilliancy to display." New York Times

So impressive diamond rings prior to New York were either rare or under-reported!

The diamond ring is so impressive for a number of reasons:

1) For a few seconds, you can see the surface of the sun as well as the corona and prominences.

2) The "diamond" is a near "point" source: so it's the brightest star-like oject ever seen by man.

3) The diamond is mometarily seen against a still-fairly-dark sky.

4) The sight, like the totally eclipsed sun, has so much visual dynamic range that what is seen cannot be accurately captured on film. In fact, for a small fraction of a second, when the sun has just appeared, the dynamic range of the sight, encompassing corona, prominences, dark sky, and a pin-point of sun, is the greatest of any sight in nature!

5) The diamond ring is a transient event, whereas the eclipsed sun is almost static.

Thus, I would argue that the rarest and perhaps most magnificent sight in nature is a great diamond ring at third contact (when eyes have achieved some degree of dark adaptation.) It lasts only a fraction of a second, whereas the sight of the eclipsed sun lasts minutes.

Can we make some assumptions about how much of the surface of the sun is showing at the moment when the diamond ring is at its maximum glory in a typical eclipse, and then estimate the astronomical magnitude of the diamond? From that, we can also state the ratio of brightness of the diamond to that of the average brightness of the brightest pointlike object normally seen in dark skys, Venus?

I have never seen a guestimate of such a number reported. Bob Morris

From: KCStarguy@aol.com To: SOLARECLIPSES@AULA.COM Subject: Re: [SE] Diamond rings! Date: Tuesday, February 02, 1999 4:55 AM

ingoing and outgoing diamond rings I saw were spectacular indeed most memorable for me too. I caught both of them on my videotape. I will isolate them in the coming months. Eric Flescher, Ed.D

From: Bob Morris morris@sce.carleton.ca To: Solar Eclipse solareclipses@AULA.COM Subject: [SE] Origin of term "Diamond Ring"!!!!! Date: Tuesday, February 09, 1999 7:20 PM

In a previous posting I said that the front page of the New York Times for Jan 25 1925 all but used the term "diamond ring."

Because the eclipse also went through Toronto, which was clouded out, I had ordered up the Toronto Globe. I just got it today!

In the issue for Jan 26 1925 we find the following *definitive* tale of the origin of the term diamond ring. (If it was in the NY Times, I missed it.)

From: Patrick Poitevin ppoitevin@village.uunet.be To: SOLARECLIPSES@AULA.COM Subject: Re: [SE] Origin of term "Diamond Ring"!!!!! Date: Tuesday, February 09, 1999 9:40 PM

Bob Morris wrote: (Patrick: Is there a posting of the month award? :-)

Yes, a free subscription to the Solar Eclipse Mailing List... Best regards, Patrick