Big telescopes don't always mean sharp images!
Contrary to the mythology known as "common sense" big isn't always best. In the world of Astronomy "common sense" tells us that the most important property of a telescope is its "light gathering" ability which is directly proportional to aperture.
Bright, transparent skies are typically associated with turbulent air thus producing brilliantly twinkling stars. Hazy, quiet humid nights often have dimmer stars which, due to the stable air, do not playfully jump around.
As the following diagram shows, during periods of bad seeing (turbulent air) large aperture telescopes will average the constantly varying distorted light rays of the twinkling stars and produce bright, steady, blurry blobs of light whereas small aperture telescopes will average fewer light rays and produce dimmer and sharper images which bounce around as individual distorted rays are transmitted.
When the seeing is good, the large telescopes come into their own and magnify steady, constant images to produce high contrast views showing intricate celestial details.
But during conditions of bad seeing, a small aperture telescope may actually outperform its large counterpart and produce sharper images. This is of particular importance when observation occurs near water bodies which induce turbulent air.
If you use your telescope during less than ideal conditions you might be better served by investing in quality optics rather than light gathering power. A small telescope with excellent optics produces better views when the seeing is bad than will a large telescope with average eyepieces.
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Ball lightning, a glowing, floating ball of lightning, has entered airplanes, floated around, and rolled down the aisles between the seats! The balls don't usually do much damage, and have been described as "playful" and "curious"!
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