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.
Technically speaking, the sun is the closest star to Earth. . The next closest known star to the Earth is Proxima Centauri, red dwarf star. approximately 4.2 light years from Earth ...