Why does the Sun not give off radiation uniformly all through the solar system?

---

Request for Question Clarification by siliconsamurai-ga on 29 Dec 2005 10:26 PST

Can you make your question a little more clear? For example, why do
you think that sunlight isn't evenly radiated from the surface of the
sun? That would let me know just what you are seeking as an answer
such as an explanation of the inverse square relationship.

---

Clarification of Question by kr54-ga on 29 Dec 2005 16:10 PST

Exactly as you said, siliconsamurai-ga----

Why do you think sunlight isn't evenly radiated from the surface of
the sun, uniformly through the solar system.

---

Request for Question Clarification by siliconsamurai-ga on 30 Dec 2005 06:05 PST

I see this is your first question on google answers so I'll explain a bit.

When a researcher asks for a clarification it means that they can't
answer your question because they don't understand the question
itself.

In this instance, you appear to be asking why something which doesn't
happen actually does occur.

Since that makes no sense I asked you to give us some hints about what
you really are asking so we know how to answer. Merely repeating my
question to you isn't a clarification because it doesn't supply any
increased information except in a negative way.

Hello kr54-ga 
  and welcome to Google Answers.  
  Thank you for asking this interesting question about out Solar System.

 As commenters tried to say, there are two possible meanings,
 so I will answer both:


 Meaning 1:

   Venus is hot,
   Mars is  cold
   Neptun is very cold .. 

In general:
  Father from the Sun, the colder it gets


This link shows how Temperature goes down with distance from the Sun
http://www.lwr.kth.se/Grundutbildning/1B1292/Applets/Climate/T-effective/T-effective.htm

 Question is :why?

 Answer : All isotropic sources of energy are like that,
          It is called Inverse Square law.

http://en.wikipedia.org/wiki/Inverse-square_law

 Meaning 2: Does Sun shine the same in all directions?

in other words: Is sun radiation isotropic?

 Answer is: Yes.

 "We all know the Sun radiates energy in all directions. The energy
radiated from the Sun measured at any fixed distance and from any
angle will be approximately the same..."
http://www.itnu.de/radargrundlagen/antennen/at08-en.html

Please, feel free to ask for clarifications.
Rating appreciated.

Hedgie

Because like anything else in a configuration like this, it follows a 1/r^2 law.

KR54,

Like Silicon Samurai, I'm still perplexed. Please clarify the question.

To my knowledge sunlight is radiated quite uniformly. Of course, there
are small nonuniformities like sunspots that give some variability,
but these are on such a small angular scale that they are irrelevant
unless you are in a spacecraft very near the surface of the sun, in
which case you're getting cooked either way.

I suppose there is some nonuniformity associated with solar latitude.
Certainly there will be small effect due to the solar oblateness so I
would expect a slightly different flux directly above one of the sun's
poles than directly above the solar equator.

The solar wind is quite variable and is strongly influenced by the
sun's magnetic field, which is roughly aligned with the poles. Large
magnetic storms on the sun give rise to solar flares which cause large
directional bursts in the solar wind, but have very little effect on
"sunlight".

As both commenters have noted, there is a strong variation in the
amount of light that reaches you depending on how far you are away
from the sun. This is a simple geometrical fact since the uniformily
radiated light gets spread more and more thinly as you get further
away. Since the area of a sphere grows quadratically with its radius,
the intensity of the sunlight must fall as the inverse square of the
distance.

Sorry, that's certainly not a clarification of any sort so I'll pass
on this question.

Hello kr54-ga. Perhaps you should provide some examples of what you
mean by the non-uniformity of sunlight.

Inverse square distribution is still "uniform." Also, it applies
precisely only to sunlight and other electromagnetic fields, not all
"radiation" so, without more information we don't know if this is an
obvious and elementary question or one about some obscure aspect of
astrophysics.