An America-Wide Solar Eclipse

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Annular means "ring-shaped." In such an eclipse the moon passes centrally in front of the sun but is out too far in its orbit to appear large enough to hide the sun's entire disk. A ring of sunlight shines out from around the moon's silhouetted form. When the moon is close enough to earth during a central eclipse, the eclipse is total—all the sun's fiery disk is hidden and magnificent sights like the sun's pearly outer atmosphere appear in a sky dark enough for some stars to come out. At an annular eclipse you don't get to see grandeur as stunning as that of a total eclipse. But you do get to see a rather impressive darkening of sky and landscape, change in the color of sunlight, weird shadows on the ground, and more.

But what about getting a sight of the sun's disk itself during the eclipse? During a partial or annular eclipse, you should never look at the sun unless you use proper protection for your eyes. You can look through shade, such as a suitably large piece of welder's glass that can be bought for about $2 or less from your local welding supply store, but only with the eyes, not with binoculars or telescope. Many small telescopes come with solar filters, but often they are poorly made. Seek out your local planetarium or astronomy club for safe telescopic views, unless you want to use a perf ectly safe alternative and try projection with your telescope or binoculars.

All you do in projection is put the sun at your back and then—being careful not to ever look into the telescope or binoculars—maneuver your optical instrument until its tube (or tubes) is casting the smallest possible shadow. The sun should now be shining into your instrument and the magnified solar image can be projected onto a screen-say, a piece of cardboard. But be careful, the eyepiece of a telescope can focus great heat in front of it. On your screen you will see a disk of light (focus the optical instrument or adjust the screen's distance to make that disk sharp-edged), possibly with some curious black speckles here and there on it. What you see is the sun, with various dark looking sunspots.

By the way, even if you have no binoculars or telescope, you can project the image of the solar eclipse with something as simple as a piece of cardboard with a pinhole in it. The image projected onto a second piece of cardboard will be tiny, but you should be able to see an ever-larger bite taken out of it as the moon moves across the sun.

Spring Peepers

Before birds ever sang, there were Earth's first singers: the frogs. One of the most familiar choruses is the high-pitched, long-carrying keening of the variety of tree frogs known as Spring peepers.

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