Which term describes the obscuring of light from one body by the passage of another between it and the observer?

Which term describes the obscuring of light from one body by the passage of another between it and the observer?

• A. Eclipse
• B. Transit
• C. Illumination
• D. Reflection

Answer: (A)

Eclipse describes the obscuring of light when one object passes between a light source and an observer, blocking some or all of the light you would otherwise see. This is what happens in solar and lunar eclipses: the Moon blocks sunlight from reaching Earth, or Earth blocks sunlight from reaching the Moon. A transit also involves one object crossing in front of another, but it’s usually described as a smaller body crossing a brighter background and doesn’t necessarily imply complete light blockage. Illumination is just light arriving on a surface, and reflection is light bouncing off that surface.

Eclipse describes the obscuring of light when one object passes between a light source and an observer, blocking some or all of the light you would otherwise see. This is what happens in solar and lunar eclipses: the Moon blocks sunlight from reaching Earth, or Earth blocks sunlight from reaching the Moon. A transit also involves one object crossing in front of another, but it’s usually described as a smaller body crossing a brighter background and doesn’t necessarily imply complete light blockage. Illumination is just light arriving on a surface, and reflection is light bouncing off that surface.