Close Brush With the Sun

Perihelion Day is tomorrow, January 4.  It occurs approximately two weeks following the Winter Solstice.  On this day the earth's center is approximately 91,402,500 miles from the center of the sun.  That puts earth about 3 million miles closer than our position with the sun in June - when we are stretched the furthest - called aphelion.

You're likely scratching you head over the fact that the overnight temps have been hovering in the single digits.  And if we're closer to the sun why aren't we melting?  

That would be a consequence of the tilt of the earth on its axis.  In the northern hemisphere we're tilted away from the sun in winter.  If you reside in the southern hemisphere you are tilted in the opposite direction and it is summertime there.  Any association with the Winter Solstice is purely coincidental.

If you are interested, a fun astronomical factoid is that the earth is distancing itself from the sun at a rate of about 1.5 centimeters a day.  That doesn't like a big deal except that over a billion years or so it might add up to something.  But not likely enough to escape the consequences of being attached to our closest star.

Our fate with the sun is preordained.  As it ages and begins to run out of fuel it will morph into a red giant phase, and all the planets in its orbit will be incinerated in a spectacular and fiery denouement.

Poof!

You're welcome.  And have a good day....