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Solar eclipses

Review your understanding of solar eclipses in this free article aligned to NGSS standards.

Key points:

  • A solar eclipse occurs when the moon casts a shadow on part of Earth.
  • Observers inside this shadow see a total solar eclipse. During a total solar eclipse, the moon fully covers the bright disk of the sun. This allows the sun’s corona, or outer atmosphere, to be visible.
  • In the moon’s shadow, the air temperature drops an average of 10°F (5.5°C). This is because the moon is blocking most of the sun’s energy from reaching that part of Earth.
  • Solar eclipses occur only during the new moon. However, they do not occur every new moon because the moon’s orbit is tilted relative to Earth’s orbit around the sun.
A total solar eclipse.
The sun’s corona as seen during a 2017 total solar eclipse. Image credit: "2017 Total Solar Eclipse" by NASA/Aubrey Gemignani, CC BY-NC-ND 2.0.

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