Earth  Sun  Planets and Moons  ID: 4390

2017 Eclipse: Earth, Moon and Sun

A solar eclipse occurs when the Moon passes between the Sun and the Earth, casting its shadow on the Earth. The shadow comprises two concentric cones called the umbra and the penumbra. Observers on the Earth who are within the smaller, central umbra see the Sun completely blocked. Within the larger penumbra, the Sun is only partially blocked.

In this animation, the Earth, Moon, Sun, and shadow cones are viewed through a telescopic lens on a virtual camera located far behind the Earth. Long focal lengths like the one used here appear to compress the distance between near and far objects. Despite appearances, the geometry of the scene is correct. The Moon's umbra cone is roughly 30 Earth diameters long, barely enough to reach the Earth, while the Sun is almost 400 times farther away.

From this perspective, we see the night sides of both the Earth and the Moon. Solar eclipses can only occur during New Moon, when the entire Earth-facing side of the Moon is experiencing nighttime darkness.
 

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Visualization Credits

Ernie Wright (USRA): Lead Visualizer
Kayvon Sharghi (USRA): Producer
Please give credit for this item to:
NASA's Scientific Visualization Studio

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http://svs.gsfc.nasa.gov/4390

Data Used:
JPL DE421
Note: While we identify the data sets used in these visualizations, we do not store any further details nor the data sets themselves on our site.

This item is part of this series:
2017 Solar Eclipse

Keywords:
SVS >> HDTV
SVS >> Moon
SVS >> Solar Eclipse
SVS >> Sun
SVS >> Hyperwall
SVS >> Eclipse
SVS >> Heliophysics
SVS >> Sun-Earth-Moon Interactions
SVS >> Sun and Earth
NASA Science >> Earth
NASA Science >> Sun
NASA Science >> Planets and Moons