li giác
Definition
- Noun (Astronomy):
- Elongation: The angular distance between a planet or other celestial body and the Sun, as observed from Earth. It describes how far the object appears to be from the Sun in the sky.
Usage Examples
- Noun:
- Li giác của Sao Kim tối nay rất lớn. (The elongation of Venus tonight is very large.)
- Các nhà thiên văn đo li giác để xác định vị trí của hành tinh. (Astronomers measure elongation to determine the planet's position.)
- Hành tinh đó đạt li giác cực đại vào ngày mai. (That planet will reach maximum elongation tomorrow.)
Advanced Usage
- "Li giác cực đại" (Maximum elongation): The greatest angular separation between a planet and the Sun, which is the best time to observe the planet in the evening or morning sky.
- Sao Thủy sẽ đạt li giác cực đại phía đông vào tuần tới. (Mercury will reach its greatest eastern elongation next week.)
Variants and Related Words
- Góc li giác (n): elongation angle. This phrase is sometimes used interchangeably with "li giác."
- Góc li giác được tính bằng độ. (The elongation angle is measured in degrees.)
Synonyms
- Angular separation: A more general term for the angular distance between two celestial objects.
- Elongation: The direct and most precise equivalent in astronomical terminology.
Notes on Usage
- Technical Term: "Li giác" is a specialized scientific term used almost exclusively in astronomy. It is not used in everyday conversation.
- Context is Key: This word will only be encountered in texts or discussions about astronomy. It is typically modified by adjectives like "lớn" (large), "nhỏ" (small), or "cực đại" (maximum).