What causes a solar eclipse and how rare is it?

A solar eclipse occurs when the Moon passes directly between Earth and the Sun, casting a shadow on Earth's surface. This alignment blocks sunlight either partially or completely, depending on your location relative to the Moon's shadow. A total solar eclipse, where the Sun is completely obscured, happens because the Moon and Sun appear nearly the same size in our sky, allowing the Moon to cover the Sun almost perfectly. Total solar eclipses occur somewhere on Earth roughly every 18 months, but any specific location on Earth only experiences one about every 375 years on average. Partial eclipses are more frequent and visible from wider areas. The rarity for a given location is what makes total solar eclipses such a celebrated astronomical event.