The earth, in its yearly elliptical orbit, reaches its closest approach to the sun Saturday, known as perihelion and about 91.4 million miles from the sun.

This July 5 the earth is farthest from the sun, about 94.5 million miles, at something called aphelion. With proper astronomical instruments a person can see the sun is closer now, as it is slightly larger than at the other times of the year. Despite Minnesota being closest to the sun in January, it is paradoxically the coldest month of the year. Days are warmer in the spring, summer and fall because the sun is higher in the sky. Also, the days are longer, giving the sun more time to heat the land, water and atmosphere.

We have gained three minutes of daylight since the winter solstice Dec. 21. Nature slows some until March, but there is still much going on outdoors now. A few examples:

• Eastern chipmunks awake but stay in and eat from the supply of food stored in underground burrows.

• Bald eagles hunt fish where open water is found, like in areas of the Mississippi and Minnesota rivers and along the North Shore.

• Think about the land-hibernating frogs (wood frogs, chorus frogs, spring peepers, and gray tree frogs) lying frozen in the leaf litter yet still alive.

• See how evergreens from pines to spruce and fir offer cover for wildlife.

• Wild turkeys scratch for acorns under oak trees.

• Overwintering mourning doves have become a common sight at southern Minnesota feeding stations.

• Up North, grouse dive down into powdery snow to keep warm a night.

• Wolves travel on the wind-packed snow of northern lakes.

• Fresh snow is a blank page on which animals write their winter stories with their prints and other markings.

• Sow bugs sleep under logs or beneath rocks.

• Icicles will grow on cold, sunny days.

Jim Gilbert taught and worked as a naturalist for 50 years.