Why Do O Stars Exhibit Weak Hydrogen Absorption Lines

question 21

Multiple Choice

Why do O stars exhibit weak hydrogen absorption lines?

• A)At these high temperatures, nearly all the hydrogen is ionized, and is therefore unable to interact with light.
• B)O stars contain very little hydrogen.
• C)O stars are too cool to excite hydrogen atoms to the first energy level from which they can then absorb visible wavelengths of light.

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Definitions:

Early Plants

Refers to the first primitive forms of plant life that began to emerge on Earth over 500 million years ago, playing a crucial role in the development of terrestrial ecosystems.

Gemma

A small asexual reproductive structure found in some plants, such as liverworts, that can develop into a new organism.

Liverworts

A group of non-vascular plants belonging to the plant division Marchantiophyta, often found in moist, shaded environments.

Lycopodiophyta

A division of plants, commonly known as clubmosses, characterized by a primitive vascular system, often found in moist, shaded environments.