When does it happen?Solar eclipse can occur only in the new moon phase of the moon. In this phase, the illuminated side of the moon is pointed away from the earth and the sun and moon are in conjunction. This phase occurs every 29.5 days. As moon continuously orbits around the earth, eclipse occurs when it is in line with earth and the sun. Although, every month there is a new moon phase that does not lead to an eclipse every time as the moon and earth are tilted at an angle. Moon’s orbit is at a tilt of 5 degree relative to earth.There are at least 2 Solar eclipses every year
Q: What exactly happens during such a Total Solar Eclipse?A: During a total solar eclipse, partial phase of eclipse takes place for about hour or more when moon slowly covers the sun but dimming of sunlight is hardly observed during this phase. Then, as moon slides totally in front of sun, the sky starts getting darker. The moon’s black disc appears as a hole in sky and peeking around the black disc should be a number of pinkish solar prominence, gigantic explosions of hot hydrogen gas that boil off from the Sun in spectacular arching shapes. At the last instant, when the Moon completely covers the Sun, observers may view two captivating sights of Bailey’s Beads and Diamond Ring Effect.
Q: How dark does it get?A: The darkness at the time of total solar eclipse can be compared to darkness of full moon night and even the stars also get visible at the day time. This sight is only observed across the areas in the path of totality while areas away from the path of totality will not get significant dark.
Q: How can I observe the partial eclipse safely?You should avoid looking directly at the sun to view partial or total eclipse with unprotected eyes as it can cause serious damage to retina and can affect your vision for the rest of life. Listed below are few methods for safely viewing the eclipse:
Solar Filters: Viewing through a special aluminized Mylar film designed specifically for eclipse viewing.
Welder’s Glass No. 14: Welders goggles or the filters for welder s goggles with a rating of 14 or higher are safe to use for looking directly at the Sun.
Viewing by projection: Use a card with a small hole in it to project an image of the eclipse on a screen, and you watch the screen, not the sun. You can use a piece of paper, or even a straw hat with a little hole in it. Just put something with a little hole in it over a flat surface and you ll see the sun s movement.
Fully Exposed and Developed Black-and-White Film: One can make your own filter out of black-and-white film, but only true black-and-white film (such as Kodak Tri-X or Pan-X). Such films have a layer of silver within them after they are developed. It is this layer of silver that protects your eyes.
Camera and Telescope Solar Filters: Many telescope and camera companies provide metal-coated filters that are safe for viewing the Sun. They are more expensive than common Mylar, but observers generally like them better because they are available in various colors, such as a chromium filter through which the Sun looks orange. Through aluminized Mylar, the Sun is blue-gray. As with the Mylar, you can look directly at the Sun through these filters.
Caution: Do not use color film or chromogenic black-and-white film (which is actually a color film). Developed color film, no matter how dark, contains only colored dyes, which do not protect your vision. It is the metallic silver that remains in black-and-white film after development that makes it a safe solar filter.
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