The visual spectrum of light, however, is but a tiny portion of the whole picture, of a huge spectrum of radiation that extends in both directions from the edges of the rainbow.
If with superhuman eyes you could see beyond red, you would encounter the "infrared" -- felt as heat on the skin -- which would merge gradually into the familiar "radio" portion of the spectrum.
In reality, the Bible makes no claim as to the age of the earth, although it does establish a minimum age.
Together they constitute the "visual spectrum" (or "optical spectrum") because it is the part of the full spectrum that is seen with the human eye.
However, radioisotope dating may not work so well in the future.
Anything that dies after the 1940s, when Nuclear bombs, nuclear reactors and open-air nuclear tests started changing things, will be harder to date precisely.
If you lost your glossary then you will need to print this one for use in the classroom.
You must write the entire definition - do not skip words. As a result, you must think about the definition that is appropriate based on the unit that you are studying.
The following is a summary of the biblical evidence presented on this website regarding the age of the earth.