Solar Phenomena — Terminology The luminous, coloured ring observed around the Sun (especially visible during a total solar eclipse) is called the:

Introduction / Context:
Understanding basic solar terminology helps decode eclipse observations and space-weather news. During a total solar eclipse, the bright solar disk is blocked, allowing the Sun’s outer atmosphere to become visible as a pearly, luminous ring. This visible envelope is central to many introductory astronomy questions.

Given Data / Assumptions:

• An observed luminous ring surrounding the Sun.
• Observation is most striking during totality in a solar eclipse.
• We need the correct scientific term.

Concept / Approach:
The Sun’s outer atmosphere comprises the chromosphere and the much more extended corona. The corona, made of extremely hot, tenuous plasma, appears as a diffuse, radiant halo when the photosphere is blocked. Terms like “nebula,” “comet,” and “asteroid” describe entirely different celestial objects and are not parts of the Sun.

Step-by-Step Solution:

Verification / Alternative check:
Any standard eclipse photo shows the structured coronal streamers and plumes, confirming the term.

Why Other Options Are Wrong:

• Nebula/Comet/Asteroid: Not atmospheric layers of the Sun; unrelated categories.

Common Pitfalls:
Confusing “corona” with “halo” caused by ice crystals in Earth’s atmosphere. The question’s wording about the Sun’s surrounding luminous ring during eclipse points to the solar corona.

Final Answer:
corona