How do solar and lunar eclipses occur?
An overview of spatial relationships between the Sun, the Moon, and Earth during eclipses of the Sun and the Moon.
Encyclopædia Britannica, Inc.
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NASA/JPLVoyager 2 arriving at Neptune after a 12-year journey, August 25, 1989.
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Encyclopædia Britannica, Inc.Each offspring is a combination of its two parents, receiving some dominant traits from its mother and others from its father.
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Encyclopædia Britannica, Inc.We're basically living in one big lava lamp.Media Editors: Michele Metych , Lauren Sims
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NASA/GSFC/SDO/HMIMagnetic fields in a sunspot pair, as observed by the Helioseismic Magnetic Imager on board the Solar Dynamics Observatory, March 29, 2010. White and black trace opposite magnetic polarities.
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Encyclopædia Britannica, Inc.A solar eclipse is a celestial phenomenon occurring when the Moon appears to block out the Sun.
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NASA/Goddard Space Flight Center Scientific Visualization StudioA sequence of images captured by the Helioseismic and Magnetic Imager (HMI), one component of NASA's Solar Dynamics Observatory. The images depict the magnetic field structure on the surface of the Sun, with white locations representing a positive magnetic field value, black locations representing negative magnetic field value, and grey areas representing zero magentic field value.
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NASAThe solar corona is a veil of plasma surrounding the Sun. This film shows what the corona looks like in the X-ray portion of the electromagnetic spectrum. The brighter areas have greater X-ray activity. The most active, shown in white, are sunspots. The black areas indicate gaps or holes in the corona.
Transcript
NARRATOR: Earth orbits the Sun while the Moon in turn orbits Earth. An eclipse occurs when all three bodies align.
While the Sun is 400 times larger than the Moon, it is also 400 times further away. This difference in perspective causes the two bodies to appear the same size. During a solar eclipse, the Moon passes between Earth and the Sun, blocking the Sun from viewers on Earth.
Whether viewers see a total or partial eclipse depends on where they are in relation to the Moon’s shadow.
The Moon casts two distinct regions of shadow on Earth during an eclipse: the inner core of dense shadow, called the umbra, and the surrounding region of partial shadow, called the penumbra.
When a viewer observes a solar eclipse from the penumbra, only a part of the Sun’s surface is obscured. This is a partial eclipse of the Sun.
For a viewer in the area covered by the umbra, the Sun is completely blocked out by the Moon. This is a total eclipse.
A lunar eclipse occurs when the Moon orbits through Earth’s shadow, preventing sunlight from illuminating it. It takes two hours for the Moon to pass through the shadow area, during which time it travels a distance of 5,000 miles.
While the Sun is 400 times larger than the Moon, it is also 400 times further away. This difference in perspective causes the two bodies to appear the same size. During a solar eclipse, the Moon passes between Earth and the Sun, blocking the Sun from viewers on Earth.
Whether viewers see a total or partial eclipse depends on where they are in relation to the Moon’s shadow.
The Moon casts two distinct regions of shadow on Earth during an eclipse: the inner core of dense shadow, called the umbra, and the surrounding region of partial shadow, called the penumbra.
When a viewer observes a solar eclipse from the penumbra, only a part of the Sun’s surface is obscured. This is a partial eclipse of the Sun.
For a viewer in the area covered by the umbra, the Sun is completely blocked out by the Moon. This is a total eclipse.
A lunar eclipse occurs when the Moon orbits through Earth’s shadow, preventing sunlight from illuminating it. It takes two hours for the Moon to pass through the shadow area, during which time it travels a distance of 5,000 miles.