'Disease' relates to its field of study 'Pathology'; by the same 'subject → scientific field' mapping, 'Planet' relates to which scientific discipline?

Introduction / Context:
Discipline-mapping analogies connect a subject or object to the scientific field that studies it. 'Disease → Pathology' names the branch of science that investigates diseases. We must mirror this with 'Planet → ?' by picking the authentic scientific discipline that studies planets and other celestial bodies.

Given Data / Assumptions:

• Pathology is the scientific study of diseases.
• Planets are astronomical objects orbiting stars.
• The correct choice must be a bona fide science discipline, not a pseudoscience or a single object.

Concept / Approach:
We keep the pairing as 'entity → legitimate field of study'. For diseases, the recognized scientific study is pathology; for planets and celestial phenomena, the recognized scientific field is astronomy (and its subfields like planetary science and astrophysics). Astrology, though historically linked etymologically, is not a scientific discipline and thereby fails the mapping requirement.

Step-by-Step Solution:
1) Extract relation: subject → scientific field.2) Disease → Pathology (valid scientific mapping).3) Planet → Astronomy (legitimate science of celestial bodies).4) Select 'Astronomy' among the options.

Verification / Alternative check:
University departments and scientific journals treat planetary studies under astronomy/planetary science. Astrology does not satisfy scientific standards of evidence and method, confirming 'Astronomy' as the accurate counterpart.

Why Other Options Are Wrong:

• Sun: A single star, not a discipline.
• Satellite: A type of celestial object; not a field of study.
• Astrology: Pseudoscience; fails the 'subject → scientific field' requirement.
• None of these: Incorrect because 'Astronomy' is correct.

Common Pitfalls:
Confusing historically related but non-scientific terms (astrology) with actual sciences (astronomy). Always select the recognized discipline.

Final Answer:
Astronomy