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Updated: Jun 27, 2026
06:14
Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
Simulating irradiance during lunar eclipses: the spherically symmetric case
Michael Vollmer1, Stanley David Gedzelman
1Fachbereich Technik, Brandenburg University of Applied Sciences, Brandenburg, Germany. vollmer@fh-brandenburg.de
Applied Optics
|November 28, 2008
Summary
During total lunar eclipses, Earth's atmosphere significantly dims moonlight. Atmospheric components like ozone and aerosols reduce irradiance, making the eclipsed Moon appear red and dim.
Area of Science:
- Astronomy
- Atmospheric Science
- Geophysics
Background:
- Total lunar eclipses offer a unique opportunity to study Earth's atmospheric properties.
- The apparent brightness and color of the Moon during an eclipse are influenced by how sunlight interacts with Earth's atmosphere.
Purpose of the Study:
- To simulate and quantify the reduction in solar irradiance reaching the Moon during a total lunar eclipse.
- To investigate the effects of various atmospheric components on the Moon's appearance during an eclipse.
Main Methods:
- A pinhole model was employed to simulate irradiance.
- Calculations considered direct sunlight, atmospheric refraction, molecular scattering, aerosol extinction, ozone absorption, and obstruction by clouds and topography.
Main Results:
- In a simplified model (spherical Earth, cloudless molecular atmosphere, no ozone), irradiance at the umbra's center was reduced by ~2400 times.
- Stratospheric ozone absorption (around 600 nm) caused a pale blue hue on the umbra's periphery.
- Typical atmospheric conditions (aerosols, ozone, clouds, land) further reduced irradiance by approximately 100-fold.
Conclusions:
- Earth's atmosphere dramatically attenuates sunlight during a total lunar eclipse.
- The composition and density of atmospheric constituents, including aerosols and ozone, significantly influence the observed irradiance and color of the eclipsed Moon.
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