What to See During an Eclipse Continued

As the moon covers the last slice of the sun, the photosphere shining through the lunar valleys creates an effect called "Bailey's beads." The last sliver of sun breaks up into a chain of bright pearls around the edge of the moon. The corona is visible on the other side of the moon at this point.  Bailey's beads with a nice prominence on the left. Photo by Fred Espenak   As the last bit of photosphere disappears, you see something called the "diamond ring" effect - the beautiful inner corona forming a ring around the moon with a brilliant white jewel of light.

	After the diamond ring disappears, you only have a couple seconds to notice the crimson-colored chromosphere before it too is eclipsed.

One surprising thing about this part of the eclipse is how quickly it gets dark. Even though we all know exactly what is happening on an intellectual level, it's still somewhat frightening on some inner, instinctual level. Fortunately, there's so much to do at this point, and the spectacle is so exciting, that this wave of horror passes quickly.

Once the sun is completely hidden, you will see the full glory of the solar corona.The corona is about the same brightness as the full moon. You don't normally see it because of the blue sky. If you were in orbit above the atmosphere, you would only have to block the bright portion of the sun to see the corona. This is what orbiting solar observatories do. They can create artificial eclipses with occulting disks and observe the corona whenever needed, and for as long as is necessary.

The second striking thing you may see during totality are the beautiful prominences. These gigantic jets and loops of gas around the edge of the sun follow local magnetic fields usually emanating from sunspots. They are the beautiful crimson color of glowing hydrogen gas.

If you can draw your eyes away from the sun for a few moments, you will notice that it has become quite dark, comparable to twilight, and that the brighter stars and planets have come out. As you can see in the wide-angle chart below, five planets will be visible. The horizon (if you have a good long-distance view) has a beautiful orange cast to it - like it's sunset all around, which it is! These are portions of the earth still in the brighter "penumbra". The area of the earth out there in the penumbral regions are experiencing a partial eclipse, but still are brightly illuminated by at least a portion of the sun's blazing photosphere. These areas are far enough away that the light's trip through the earth's atmosphere colors the distant scene yellow and orange, just like at sunset. See a Quicktime animation of the eclipse as viewed from Aruba: 1.5MB or 533k. (Note the location of the planets as shown above.) At our location on the southern tip of Aruba, we'll have about 3 minutes and 32 seconds of total eclipse. As this time expires, the sun will once again emerge from behind the moon (called third contact) and we'll see the chromosphere, followed by the diamond ring and Bailey's beads, and another hour and a half of partial eclipse. The very last portion of the sun is uncovered at fourth contact, everyone is exhausted and we all retire for refreshments under the sunny skies of beautiful Aruba.  [All Photos unless otherwise noted by Ron Hipschman]

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What to See During an Eclipse

This resource is presented by The Exploratorium and NASA's Sun-Earth Connection Education Forum. Visit the Observatory for more infomation.

The Exploratorium 1998