Eyeglasses made of nylon were introduced in the late 1940s. Because of brittleness and other problems, eyeglass manufacturers switched to blended nylon (polyamides, co-polyamides and gliamides). Today's blended nylon frames are both strong and lightweight.
Venus is the closest size to Earth and is sometimes called Earth's sister planet.. Its diameter is 95% of Earth's but its mass is only 81% as much.
Venus is the closest planet to Earth (it's also the most similar in size). But its proximity to our planet depends on the orbits of both. The two planets travel in ellipses around the sun, and so the distance between them is constantly shifting.At its farthest, Venus lies 162 million miles (261 million kilometers) away. Venus takes 224.7 Earth days to travel around the sun.It makes its closest approach to Earth about once every 584 days, when the planets catch up to one another. On average, it is 25 million miles (40 million km) away at this point, though it can reach as close as 24 million miles (38 million km).enus is the closest planet to Earth (it's also the most similar in size). But its proximity to our planet depends on the orbits of both. The two planets travel in ellipses around the sun, and so the distance between them is constantly shifting.