Noun. 1. invariant-a feature (quantity or property or function) that remains unchanged when a particular transformation is applied to it. characteristic, feature-a prominent attribute or aspect of something; the map showed roads and other features; generosity is one of his best characteristics.
The part of the sun that is going to emit the most visible light is going to be the Photosphere.he photosphere is the layer of the sun that emits visible light.  The light is emitted by hydrogen atoms and is bright red. Edit. Share to: Answered. In Astronomy.
For this reason, solar radiation is sometimes also called shortwave radiation. Most (44%) of the sun's radiation is in the visible wavelengths (0.4 (violet) to 0.7 (red) micrometers). Solar radiation falling outside of this range is not visible to humans, even though it is very intense! The sun's radiation peaks at about 0.5 micrometers, which corresponds to the color blue-green. Red is the longest visible wavelength, and wavelengths longer than 0.7 um are called infrared. Nearly 37% of the sun's radiation is in the slightly longer infrared wavelengths (0.7 to 1.0 micrometers).