Observing the

An easy way to locate the Sun in your telescope is the shadow method. Insert a low-magnification eyepiece into the eyepiece holder and point your telescope more or less toward the Sun. Then, watching the shadow of the tube on the ground, carefully orient the telescope until its shadow is smallest, meaning the tube will be aligned directly at the Sun and therefore not casting a long shadow. Look in the eyepiece and make more fine-tolerance adjustments to center the Sun's disk. Once the Sun is centered, you can use higher magnification to study the surface in more detail.

Like the Moon, planets, and stars, if the Sun is too low in the sky, you'll be forced to look through excess atmosphere, which can smear out the subtle features and blur even the obvious ones. However, if you wait until the Sun is high in the sky, noon and afterwards, you risk having the Sun's features distorted by the turbulent air cells I mentioned earlier. The best time to look at the Sun through a telescope is during the mid to late morning hours, when it is more than halfway up into the sky, between 45° and 75° in altitude.

Seeing quality at any time can be improved if you do two additional things. First, avoid setting up your telescope on tarmac or concrete. These surfaces absorb and reradiate heat rapidly, which in turn mixes violently with cooler air above the ground, creating turbulence.

Second, keep your telescope shaded. The unrelenting heat of the Sun beating down on the telescope tube generates internal tube currents that can foul the image. You can easily construct a lightweight cardboard collar and mount it near the telescope's aperture so the tube is shaded while observing. Another low-tech alternative is to drape a sheet or tarpaulin across a line strung between two poles that are inserted into the ground or held in place with bricks. The telescope's aperture simply protrudes slightly from a parting or slit in the curtain, while the rest of the instrument is shielded from the Sun. A bit ungainly, perhaps - and not much use under windy conditions or when the Sun is near the zenith -but this method has the advantage of placing the observer in the shade, which not only adds comfort but keeps the eye from being dazzled by the sunlight, something that could prevent you from seeing more subtle detail on the Sun's surface.

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