For the current testing, an injection is made into the clear fluid in the center of the eye, and the virus finds the correct part of the retina to treat. If the treatment is found to work and approved for use, for some people color blindness could be reduced or cured with a single visit to the ophthalmologist.
Why does it take so long for the radio waves to travel through space? Actually, radio waves travel very quickly through space. Radio waves are a kind of electromagnetic radiation, and thus they move at the speed of light. The speed of light is a little less than 300,000 km per second. At that speed, a beam of light could go around the Earth at the equator more then 7 times in a second. The reason that it takes so long for radio messages to travel in space is that space is mind-bogglingly big. The distances to be traveled are so great that even light or radio waves take a while getting there.
Electromagnetic radiation (which includes radio waves, light, cosmic rays, etc.) moves through empty space at the speed of 299,792 km per second. Sunshine is a familiar example of electromagnetic radiation that is naturally emitted by the Sun. Starlight is the same thing from Suns that are much farther away. Electromagnetic radiation travels in waves that vibrate at different frequencies. Radio waves are in the range of about 10 kHz (or ten thousand waves per second) to 100 GHz (which is one hundred million vibrations per second).