Viewing Kentucky's total solar eclipse can be a truly amazing experience, but keep in mind there are certain risks associated with eclipse viewing. Special attention should always be paid to safety to ensure a happy viewing experience. To avoid potential accidents or health problems, here are some things you need to remember before turning your gaze to the sky August 21, 2017.
While this may seem to be common knowledge, it should be pointed that the sun is an extremely bright celestial object. In fact, it is approximately 120 billion times brighter than stars of the first magnitude and 460,000 times brighter than a full moon. As a result, there is a very real risk of causing serious damage to the eyes if you stare directly into the sun for even the shortest amount of time.
While the sun may appear darker through sunglasses or other filtering devices, this is only because the visible light has been weakened. Infrared radiation, which is harmful to the eyes, is usually not shaded. Since the human eye does not feel the brightness of infrared radiation, serious damage could be occurring undetected.
Before we get into the proper ways to view a total solar eclipse (and the equipment required to do so), let’s examine a few ways that are incorrect and potentially hazardous.
First a foremost, the sun should never be looked upon directly with the naked eye. Even sunglasses do not provide enough protection to view the sun directly. The sun should also not be viewed directly using a telescope or binoculars. Those wishing to take photos of an eclipse should not aim their viewfinders directly at the sun. Problems ranging from retina problems to even eyesight loss could occur if the sun is viewed incorrectly.
According to NASA, “Even when 99 percent of the sun's surface is obscured during the partial phases of a total eclipse, the remaining photospheric crescent is intensely bright and cannot be viewed safely without eye protection.”
Fortunately, a total solar eclipse can be viewed when the sun is blocked out in totality, according to NASA. But even when the sun is only 99% blocked, you'll need to take precautions with some special glasses. These glasses, which MUST be ISO Certified and CE approved, can be bought just about anywhere (Wal-Mart locations, dollar stores, convenience stores, tourism offices, accommodations, etc.). They typically cost anywhere from $1 to $3 per pair.
The safest and most inexpensive way to prevent eye damage while viewing an eclipse is by using projection. With projection, a pinhole or small opening is used to form an image of the sun on a screen placed approximately three feet behind the opening. Multiple openings can be used to cast a pattern of solar images on a screen. These items can be created with perfboard or a loosely-woven straw hat or even interlaced fingers.
Overlapping leaves from a broad-leafed tree can create crescent-shaped images on the ground. Binoculars or a small telescope mounted on a tripod can also be used to project a magnified image of the sun onto a white card. While this offers a way to view partial phases of an eclipse safely, care must be taken to ensure no one looks through the device. The main advantage of any type of projection method is the no one is looking directly at the sun.