Seeing

Definition

Seeing describes the quality of atmospheric conditions that affect the clarity and stability of images observed through telescopes. It is primarily influenced by air turbulence, which can cause stars to appear to twinkle or blur.

5 Must Know Facts For Your Next Test

1. Poor seeing is caused by atmospheric turbulence, which distorts the light from celestial objects.
2. Astronomers quantify seeing using the term 'seeing disk,' which represents the apparent diameter of a star image in arcseconds.
3. Adaptive optics systems are used to compensate for poor seeing by adjusting telescope mirrors in real-time.
4. High-altitude observatories and space telescopes experience better seeing due to reduced atmospheric interference.
5. Seeing conditions can vary significantly even over short periods, influencing observational data quality.

Review Questions

• What is 'seeing' in the context of observational astronomy?
• How does atmospheric turbulence affect astronomical observations?
• What technologies do astronomers use to mitigate poor seeing?

Related terms

Adaptive optics: Technology that improves image quality by correcting for distortions caused by atmospheric turbulence in real-time.

Seeing disk: A measure of the blurring effect of Earth's atmosphere on starlight, expressed as an angular diameter.

Turbulence: Irregular or chaotic changes in wind speed and direction that cause variations in air density, impacting astronomical observations.