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.
Often called Earth's sister planet, Venus is the closest in size, with a mass of more than 80 percent that of our planet and a diameter of only a few miles less. It is also the closest planet to our own in terms of location.ensity, mass, and volume. Venus is a rocky, terrestrial planet like Earth, and likely formed the same way at the same time. It has a mass of 4.87 trillion trillion kilograms, about 82 percent that of its sister planet.