Discussion Overview
The discussion revolves around the transparency of the atmosphere and the relationship between absorption lines and the spectral signatures of atmospheric gases, particularly oxygen and nitrogen. Participants explore the implications of these concepts in the context of visible light and other parts of the electromagnetic spectrum.
Discussion Character
- Exploratory, Technical explanation, Debate/contested
Main Points Raised
- One participant notes a conflict between the claim that atmospheric gases like oxygen do not have absorption lines in the visible spectrum and the information from a source indicating that oxygen has many visible lines in its spectral signature.
- Another participant points out that the majority of the atmosphere is composed of nitrogen, and that nitrogen and oxygen exist as diatomic molecules (O2 and N2), which may have different spectral lines than their constituent atoms.
- A participant expresses uncertainty regarding the presence of absorption lines for N2 and O2 in the visible spectrum, referencing a Wikipedia article that shows many spectral lines for air in visible light.
- One participant explains that while absorption and emission lines differ in intensity, the atmosphere does not have strong first-order absorption lines in the visible range, but does have weak ones, primarily from oxygen and water molecules.
- A later reply questions whether air has strong absorption lines in the electromagnetic spectrum outside of visible light.
Areas of Agreement / Disagreement
Participants express uncertainty and confusion regarding the relationship between absorption lines and the transparency of the atmosphere. Multiple competing views remain about the presence and significance of these lines in both the visible spectrum and other parts of the electromagnetic spectrum.
Contextual Notes
There are limitations regarding the definitions of absorption lines and the conditions under which they are observed, as well as the distinction between atomic and molecular spectral lines.