I don’t know if you’ve noticed, but the sun seems so bright lately, especially late in the day. I keep thinking I’m having some issues with my vision, or maybe it’s just that I’m getting a little older and can’t handle it. It just seems the sun this fall has been so much brighter than during the summer, so I looked into it, and sure enough, it is brighter.

But a brighter sun in the fall is nothing new – it happens every year. Maybe I’m just noticing it more this year because every time I seem to be driving lately, I’m driving west into the sun, and it’s blinding.

Actually, the sun continues to get brighter through the fall and into January, when the sun is at its brightest, because that’s when Earth is closest to the sun.

Because Earth rotates on a tilt, and because it has an egg-shaped orbit around the sun, even though we’re closest to the sun in the winter time, the northern hemisphere is colder because it’s tilted away from the sun, so the days are shorter and temperatures are lower. The sun appears lower in the sky, and its rays have to pass through a greater thickness of atmosphere in the winter.

On Mercury, the closest planet to the sun, the sun is 11 times brighter than it appears on Earth.

On Pluto, the furthest planet from the sun, the sun only appears to be a bright star in the sky.