Do you ever feel like summer whooshes by and winter drags on?
I learned today that the opposite is true — the earth actually moves faster in winter.
From the New York Times:
the time between the spring and fall equinoxes in the Northern Hemisphere is slightly greater than that between fall and spring, the earth — being at that time closer to the sun — moving about 6 percent faster in January than in July.
I’d always known that the earth is closest to the sun in January and farthest away in July. These points are known as perihelion in January, when the earth is closest to the sun, and aphelion in July, when the earth is farthest from the sun.
(In fact, the seasons are caused by earth’s tilt toward or away from the sun, not the earth’s proximity to the sun. That’s why northern and southern hemispheres have opposing seasons. The official name for earth’s axial tilt of about 23.5 degrees is the “obliquity of the ecliptic.” You can now use this fact to win bar bets.)
Anyway: I somehow managed to get through college physics, and working as an astronomy teaching assistant, without realizing this fact: Winter passes by faster than summer!
Of course, it doesn’t feel that way to me. Probably because summer is filled with sun and fun. How’s that for relativity?