Solar eclipse

On October 25, a partial solar eclipse (Surya Grahan) is visible in Bengaluru and other parts of India, except for a large area of the states in the north-east.

• Earlier, there was an eclipse that occurred on October 17, 1762, which happened to be the day of Deepavali.

• Even in 1995, there was a total solar eclipse on October 24 which also happened on the festival of lights.

About solar eclipse

• A solar eclipse occurs when the Moon is positioned in between the Sun and the Earth for a few minutes.

• Under certain-alignment, the Moon partially or fully blocks the Sun’s light and instead casts its shadow on Earth. That is why, there can be a partial or a total solar eclipse, depending on how much portion of the Sun’s disc gets hidden by the Moon.

• In a partial solar eclipse, only the edge of the Moon’s shadow falls on the northern hemisphere. Solar eclipses happen every 18 months somewhere on Earth.

• Unlike lunar eclipses, solar eclipses last only a few minutes.

• The shadow consists of two parts, the umbra, where the Sun is completely blocked, and the penumbra, where the Sun is partially obscured. People in the umbra will see a total eclipse, while people in the penumbra will see a partial eclipse.

Lunar eclipse

• The Moon moves in an orbit around Earth. At the same time, Earth orbits the Sun. Sometimes Earth moves between the Sun and the Moon. When this happens, Earth blocks the sunlight that normally is reflected by the Moon.

• Instead of light hitting the Moon’s surface, Earth’s shadow falls on the Moon. This is an eclipse of the Moon, or a lunar eclipse.

• A total lunar eclipse occurs when the Moon and the Sun are on exact opposite sides of Earth.

• Although the Moon is in Earth’s shadow, some sunlight reaches the Moon. The sunlight passes through Earth’s atmosphere, which filters out most of the blue light.

• This makes the Moon appear red to people on Earth. Total lunar eclipses are rare.

• A partial lunar eclipse happens when part of the Moon enters Earth’s shadow. A lunar eclipse can occur only when the Moon is full.