![]() Stars have been symbolic of divine guidance and protection. They have become a sacred and spiritual symbol for many religions all over the world.įor centuries stars have had many different meanings and that changes depending on what culture you were born into. Stars are a large part of our history and current culture. Our fascination with the heavens combined with mathematics & mythology has produced one of the most common symbols to this day. In a way, they are the ultimate representation of self-reliance and resourcefulness. Stars are absolutely amazing, they are basically enormous balls of gas held together with nothing but the power of their own gravity. How many times have you gazed up into the heavens and made a wish? Or used the term, “Reach for the Stars,” to encourage someone you love? Stars are majestic and untouchable it’s no wonder they have constantly been an inspiring sight for humanity. ![]() The symbol of a star has always been steeped with awe and wonder, you only have to stare up into a clear night’s sky to experience the total realisation of inner peace and absolute insignificance all at the same time. Even your right and left eyes have different suture lines - so you might see four points with one eye, but five with the other.īut the point of it all is - there's nothing like being dazzled by a little starlight. But, because they are 'organic', every human eye has slightly different suture lines. ![]() This light gets bent, giving the star its characteristic four points.Ī similar thing happens with your eyes, thanks to the suture lines inside the lens of your eyeball bending the light. Why?īecause in the Hubble Space Telescope, the smaller secondary mirror is held in position by four cross hair-like struts, and the incoming light has to travel past these struts to land on the bigger main mirror. Whenever there's a star in the image, that star has four points or spikes - even though it's a round little dot. You've heard of the famous Hubble Space Telescope, which was launched in 1990. Now here's an example of pointy stars you would have seen dozens of times, and perhaps never noticed. Whenever light passes either around an object, or through a slit inside an object, it bends and changes its direction. These suture lines bend the waves of light as they travel through, and past, them. The front one is a regular Y-shape, while the back one is an upside-down Y-shape. These fibres meet and blend at Y-shaped suture lines. They are actually transparent cells that are both long (up to 12 millimetres) and skinny (3 to 10 microns in diameter). ![]() (If you want to learn more, look up 'lens morphogenesis'.)Īnd third, there are lens fibres that make up the bulk of the lens. At the equator, its cells also make new lens fibres that migrate toward the centre-line of the lens. It regulates the volume and saltiness of the lens. This layer of cells reaches back to the equator (or widest part) of the lens. It's a thin layer of simple cuboidal cells, located at the front half of the lens. It varies between two and 28 microns in thickness (by comparison, a fibre of hair is about 60 microns thick). This membrane is a bit like a plastic bag. It has three main parts.įirst, the lens capsule wraps around the lens, and holds it together. By the time you reach 70, all you get is one lousy dioptre.Īnatomy of the lens (Source: Adapted from Openi) If you want to look at both distant and near objects sharply, you need glasses. So as you look at distant, and then near, objects, the lens changes shape to ensure that the image always lands exactly on the retina.īut it's only when you are very young, that your lens can change its shape a lot, and vary its optical power by up to 15 of its 18 dioptres.īy the time you reach 45 - 50 years of age, your range of adjustment is down to only two dioptres. Thanks to little muscles attached near the equator, the lens can change its shape. Side-to-side, the lens is about 10 millimetres in diameter, but front-to-back it's about 4 millimetres. This lens inside your eyeball looks like an asymmetrical flattened ball - it's more flattened at the front, more rounded at the rear. The lens has an optical power of 18 dioptres. The lens does the remaining one third of the bending of the light. Anatomy of the eye(Source: BruceBlaus/Wikimedia Commons)
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