• The solstices mark the brightest and darkest days of the year, but the temperatures don't reflect that because it takes time for Earth's land and water to heat up and cool down.
• Some believe that since Earth's rotation is slowing down, each new solstice sets a new record for daytime length. But that's not the case. Instead, changes in the distribution of Earth's mass can subtly tweak our plant's rotation rate.

The Earth's axis of rotation is tilted about 23. degrees relative to Earth's orbit around the sun. This tilt causes the Northern and Southern Hemispheres to get unequal amounts of sunlight over a year.

The Earth's axis is tilted most closely toward the sun for two moments each year. These ...