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.
The core is the only region in the Sun that produces an appreciable amount of thermal energy through fusion; 99% of the power is generated within 24% of the Sun's radius, and by 30% of the radius, fusion has stopped nearly entirely.