What is transit mean in space?

When one object crosses in front of another in space, it is known as transit. For example, when the Moon passes between the Earth and the Sun, the Moon is ‘transiting‘ the Sun.

Why is it important?

Just like objects in our solar system that transit the Sun, there are objects outside our solar system too that transit stars there. These objects include planets known as explants, and their transit help scientists identify these planets.

If the orbit of a planet is lined up right, the planet is lined up right, the planet will transit the star it orbits. When this happens, the light from the star dims by a small amount of time between each transit. This is how scientists discovered seven exoplanets around a star called TRAPPIST-1. There of these planets were discovered in 2015, while four more were identified in 2017.

Bottomline, transits not only help scientists identify new planets but also understand the world beyond our solar system.

The transits we can see

From Earth, there are two main transits that can be seen by people. One is the transit of the Moon, as it passes the Sun. this is when we witness a solar eclipse. The other is the transit of the planet Venus when it passes between the Earth and the Sun during its orbit.

While solar eclipse can be observed often, the transit of Venus cannot be seen frequently because of how he orbits of Venus and Earth are lined up. The last transit of Venus was on June 6, 2012. The next one, however is not until 2117!

 

Picture Credit : Google