To Sun: When Earth Is Closest

The date of perihelion isn't fixed forever. Due to a phenomenon called (the slow wobble of Earth’s axis) and the gravitational pull of other planets, the date of perihelion shifts forward through the calendar by about one day every 70 to 100 years. In the distant past (around 1246 AD), perihelion coincided exactly with the December Solstice. In several thousand years, perihelion will actually occur during the Northern Hemisphere’s spring.

While the tilt is the primary driver of seasons, perihelion does have a subtle influence on our climate. when earth is closest to sun

If you asked a random person on the street, "When is the Earth closest to the Sun?" the most common answer would likely be, "During the summer." The date of perihelion isn't fixed forever

If distance were the primary driver of seasons, the entire planet would experience summer simultaneously in January. In several thousand years, perihelion will actually occur

The Sun’s energy reaching Earth is about 6–7% higher in January than in July. That sounds huge, but because of the tilt and atmosphere, it doesn’t override seasons. Still, it’s a measurable input: northern winters are slightly warmer than they’d otherwise be.

Earth is tilted at an angle of about 23.5 degrees. During January: