A solar eclipse occurs during a new moon phase. During a new moon, the moon is located between the Earth and the Sun. This alignment causes the moon to cast a shadow on a portion of the Earth, resulting in a solar eclipse. Let's explore this in more detail:

1. The New Moon Phase:
- The moon goes through different phases as it orbits around the Earth.
- During a new moon phase, the moon is not visible from the Earth because the side of the moon facing us is not illuminated by the Sun.
- At this time, the moon is located between the Earth and the Sun, with the Sun and moon appearing to be in the same region of the sky.

2. Alignment of the Sun, Moon, and Earth:
- During a new moon phase, the Sun, moon, and Earth are approximately aligned in a straight line.
- The moon is positioned in such a way that it blocks the Sun's light from reaching certain areas of the Earth, causing a shadow to be cast on the Earth's surface.

3. Types of Solar Eclipses:
- There are different types of solar eclipses, including total, partial, and annular eclipses.
- In a total solar eclipse, the moon completely blocks the Sun's light, resulting in a temporary darkness known as totality in the regions within the path of the eclipse.
- In a partial solar eclipse, only a portion of the Sun's light is blocked, and the eclipse is visible as a partial darkening of the Sun.
- In an annular solar eclipse, the moon is farther away from the Earth, and it does not completely cover the Sun, leaving a ring of sunlight visible around the moon.

In summary, a solar eclipse occurs during a new moon phase when the moon is positioned between the Earth and the Sun, blocking a portion of the Sun's light from reaching the Earth. This alignment causes a shadow to be cast on the Earth's surface, resulting in a solar eclipse.