If The Sun Heats The Earth, Why Is Space Cold?

As a skill website , it ’s light to get bogged down in questions like is therelife on Enceladusandwhere are all the aliens , when people are struggling with more basic ( but fun ! ) questions likewhy ca n’t we power our motorcar with magnetsandcould people catch one’s breath the air on Mars .

One such interrogative it appears people have is " if the sunlight is in the sky , why is there heating on globe but not in the sky ? " asked in the Facebook groupPhysics is Fun(which it IS ) .

First off , space is cold , with the backdrop temperature being an medium of2.7 Kelvin(−270.45 ° C or −454.8 ° F ) . And the Sun is indeed hot , in perplexing agency . The nitty-gritty reaches temperature over 15 million ° C ( 27 million ° F ) while the surface ( the photosphere ) drops off to around 5,500 ° vitamin C ( 10,000 ° F ) , while the Sun ’s corona ( taboo atmosphere ) vex spicy further aside from the photosphere , reaching temperature of   3.5 million ° hundred ( 2 million ° fluorine ) .

So why is n’t outer space hot ? Well , this seeming paradox probably add up from masses think about the Sun intuitively as a hot fire , heating the planet like a toasty marshmallow near a balefire . This is n’t how planet are warm up . The high temperature we feel on Earth is not lineal heat energy energy from the Sun , but the result ofsolar radiationemitted from the Sun ( wavelength across the electromagnetic spectrum , includingvisible light)interacting with atom on Earth .

With few particles to interact with in the ( almost ) vacuum of distance , there is not enough matter to heat via irradiation . However , this does n’t mean that you’re able to send a starship closelipped to the Sun and anticipate to receive very inhuman temperature . When you put thing in the way of the Sun ’s radiation , it is going to heat up .

On its near approach , NASA ’s Parker Solar Probe ’s solar shields for obvious example , will face temperatures of 1,400 ° C ( 2,600 ° farad ) as it tries to keep its payload at around elbow room temperature . This is as it passes through the Sun ’s corona at speeds human - made object havenever antecedently achieved .