June 10th annular eclipse for members in and around Ontario

[OzEclipse]

As I'm sure most of you are aware, on the morning of June 10 the sun will undergo an annular eclipse.

This article /observing guide specifically deals with the view from parts of Ontario, where a very deep partial eclipse is near maximum as the Sun rises. The situation is similar to a lesser extent in parts of Ohio and upstate New York. At maximum eclipse in the Toronto region, the moon covers about 87% of the Sun(location dependent) measured by diameter obstructed or 94% by area obstructed. Maximum eclipse occurs just minutes before or after sunrise depending which side of the eclipse at sunrise line you are on. East of the line, max eclipse occurs after sunrise, west it occurs before. To a lesser extent, this also occurs east and west and to the south but due to the reduced obscuration of the Sun, the effect is not as obvious.

Potential viewing locations. These are not exclusive.
For example, in my old stamping ground of southwest
Ontario, the countryside around London is all very flat
agricultural country and I remember many occasions of
seeing a dull red Sun or Moon perched on the horizon.
However, if you can't find a local flat horizon to the
northeast, these lake shores are possible viewing locations

You might think, "Damn, we'll miss half of it." In fact that means that you can observe a really interesting phenomena that, from my experience having observed a similar event in 2013, is much more interesting than simply watching the progress of a partial eclipse.

Astronomical twilight will occur at ~3am. The first faint glimmer of light will appear on the horizon. Twilight will progress, brightening normally until about 4:45am. At this point, the sun is still about 7 degrees below the horizon(depending upon your specific location). This is when first contact between Sun and Moon occurs.

From about this point until sunrise at 5:30 ish, twilight brightening will slow then stall as the moon progressively blocks the sun. Eventually it will seem to reverse and start to get darker.


You won't be able to see that familiar brightening glow on the horizon indicating where the sun will rise. Instead, you will only see a very dim dull diffuse glow more like the breaking first light of the morning. Something in the back of your head tells you it's not right but you can't pick it. Even if you don’t want to leave the house, you can observe all of this from an east-facing window.

The sky just before sunrise on May 10, 2013 from the edge
of the Great Sandy Desert in the West Australian Pilbara.

Depending upon the elevation of your horizon, you will next see two points of light appear on the horizon. The sun will rise in the northeast. If you can get to somewhere with a low horizon, looking northeast across one of the lakes, this will give you the best view.

First the point on the left will poke over the horizon.

Then the right horn pokes over the horizon.

Slowly the “devils horns sunrise” will progress.

The advantage of living in North America with its grubby air polluted skies is that the Sun appears very dim and dull on the horizon. Here in Australia, unless the wind has kicked up dust or we have bushfire smoke, the Sun is much too bright to observe as it rises or sets on the horizon. If the rising sun is dull red, or orange, it’s safe enough to look at without protection. In fact, if it’s dull red or dull orange and easy to look at with the unprotected eye, you probably won’t see anything through eclipse glasses because it’s not bright enough. Just glance at it, don’t stare for extended periods. If you glance at the full sun while you are out walking during the day or look into it at the end of a road while you are driving, you don’t go blind, nor will you during an eclipse. The danger comes from extended staring concentrating the heat on one part of the retina.

During this horizon grazing period, the thin solar crescent could appear highly distorted as was the case during this sunrise annular eclipse my friend and I observed in 2013.

As it rises it brightens rapidly, then you should not look at it unless you can get hold of some eclipse glasses or use a pinhole projector. You will know when because it will quickly get uncomfortable to look at. But, in my experience, the most interesting part is the period from first contact when it is still 7.5 degrees below the horizon, the weird inverting twilight and then the brief period as it rises at maximum eclipse. The rest, is just a partial eclipse and not especially interesting. You can make yourself a pinhole projector to watch that if you can’t find eclipse glasses.

In my experience, 14 totals, 3 annulars, and 8 partials including a number near sunrise or sunset(1983, 1984, 2002, 2008, 2013), the interesting part is when the Sun is below the horizon and when it is on the horizon.

The late Bengt Alfredsson peaking through his solar filter


Enjoy & I wish you clear skies,

Joe

[messier 111]

thx , nice pics .

[John Baars]

I hope you'll have clear skies!

[helicon]

Thanks for the heads up and observing tips Joe!