gegenschein
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Definition
Noun: A very dim, diffuse patch of light visible in the night sky at the point directly opposite the Sun (the antisolar point). It is caused by the backscatter of sunlight by interplanetary dust particles.
Usage
The term is used specifically in astronomy to describe a faint optical phenomenon. * Astronomers study the gegenschein to understand the distribution of dust in the solar system. * Observing the gegenschein requires a very dark, moonless night away from light pollution.
Advanced Usage
- In Context: The is part of a larger, extremely faint band of light called the zodiacal light, which traces the plane of the solar system. The is the brightest point along this band, located opposite the Sun.
Variants and Related Words
- Counterglow: A direct synonym for .
- Zodiacal Light: A faint, diffuse triangular glow of sunlight scattered by interplanetary dust, visible along the ecliptic. The is a concentration of this light at the antisolar point.
- Antisolar Point: The point in the sky directly opposite the Sun.
Synonyms
- Counterglow
Related Terms (Not Phrasal Verbs or Idioms)
- Backscatter: The scattering of light or particles back toward the source, which is the physical process that creates the .
- Interplanetary Dust: Microscopic solid particles (micrometeoroids) scattered throughout the solar system, responsible for scattering the sunlight.
Noun
- a faint spot of light in the night sky that appears directly opposite the position of the sun; a reflection of sunlight by micrometeoric material in space