noun
- a faint luminescence visible in the night sky, caused by chemical reactions in the upper atmosphere
Usage: atmospheric science
Examples
- The nightglow was barely visible to the naked eye but clearly detected by the sensitive instruments.
- Atmospheric scientists study nightglow to understand chemical processes in the upper atmosphere.
- The green nightglow is caused by oxygen atoms emitting light at high altitudes.
- Nightglow appears as a faint band of light along the horizon on clear, dark nights.
- Researchers measured the intensity of nightglow to monitor atmospheric conditions.
- The nightglow phenomenon occurs continuously but is only visible when the sun is below the horizon.