Why is Summer Hotter than Winter – and the Vernal Equinox

Sep 25, 2011

Do you know why Summer is hotter than Winter?

Most people are confident that they know the answer to this. Because the earth is closer to the sun in summer than it

is in winter. Right?

No, not right. This is one instance when most people are wrong. The earth is not closer to the sun in summer.

The earth does not spin in a direct up and down axis, but is tilted at an angle of 23 degrees. Because of this tillt, for six months of the year the north pole is on the side tilted away from the sun, and for six months it is on the side tilted towards the sun.

These cool photos from a NASA satellite show the amount of sunlight hitting different parts of the earth on different days.

Seasons_msg_2010-2011

NASA also has a time lapse video of the process

http://en.wikipedia.org/wiki/File:Seeing_Equinoxes_and_Solstices_from_Space.ogv

It is warmer in summer than winter because 

– the days are longer, with more hours of sunlight heating the earth.

-the sun is higher in the sky, meaning more sunlight shines on the earth more directly.  

Earth

At 9am today, September 23, it is the vernal equinox. The sun will be directly above the equator, and it is the first real day of Spring. There will be 12 hours of daylight, and the same amount of night. The days will get longer until the longest day of this year, December 22nd.

The days will be longer than the night till the next equinox, on March 19th 

For this six months of the year – from today till March 19th – we in the Southern Hemisphere are on the side leaning towards the sun. 

This time lapse video from NASA satellite and shows how the light from the sun shines on the earth at different angles.

Sometimes our ‘mental models’ of how things work are wrong.

Jonathon Drori discusses these incorrect mental models in this TED talk

Happy Equinox.

 

 

 

what are nitrates and viagra conflict, husband with high sex drive, will your penis size increase with exerciee, get hard pill, natural low libido stimulant, fictionextreme penis enlargement, how to legally buy generic viagra online, how much viagra in dubai, vein hurts after penis enlargement, why do i feel high when i take viagra, average penis size at age 13, benefit of butter sex drive, how much alcohol can you drink with viagra, how big is a soft penis, vitamins for male sex drive, maximun penis enlargement pill, how to masturbate well men, when to take viagra for fun, penis is overtrained penis enlargement, does dialysis affect sex drive in men, no sex drive is non human, penis enlargement age require, how to enlarge penis length naturally, how long do male viagra last, trumale male enhancement reviews mens health, normal sex drive for men, azul male enhancement, what does an increased sex drive mean, supplements that increase male sex drive, how to tell if someone has high sex drive, how to explain to a doctor about male enhancement, penis growth excersise, penis growth with out pills, boost libido drugs, viagra take with food, what is price of viagra, best viagra alternative over counter, where to buy priligy, where to buy generic viagra online in canada, how to extend sex time, my boyfriend is always tired and has low sex drive, buy x rock male enhancement, 5 hour erection, best natural cure for erectile dysfunction, factors in penis growth during development,