Earth is closest to the sun at what part of its orbit?

Earth is closest to the sun at the point in its orbit called the "perihelion" .

Our planet passes that point in its orbit sometime during the first few days
of January.

Here the dates of perihelion passage in 2018 and the next few years.
The times are Central Daylight Time (Chicago & Dallas time).

2018  January 2, 2018  11:34 pm
2019  January 2, 2019  11:19 pm
2020  January 5, 2020   1:47 am
2021  January 2, 2021   7:50 am
2022  January 4, 2022  12:52 am

These are the moments when the Earth will be
CLOSEST to the sun in its orbit.

This is what i found on google “according to the collision theory, the following criteria must be met in order for a chemical reaction to occur: molecules must collide with sufficient energy, known as the activation energy, so that chemical bonds can break. molecules must collide with the proper orientation.” i hope this information you.