The Naked Scientists

The Naked Scientists Forum

Author Topic: Does the Sun reflect light?  (Read 2375 times)

Offline Thebox

  • Neilep Level Member
  • ******
  • Posts: 3158
  • Thanked: 45 times
    • View Profile
Does the Sun reflect light?
« on: 12/02/2016 08:42:46 »
It is apparent the Sun emits light, but it is not so apparent if the Sun reflects other light from other stars or inverted light reflected  from bodies or absorbs it fully,?


added - does a light  bulb element when turned on, reflect light?


If there was only the sun, and no other matter in the universe or stars, so there was no other emitted light , so the sun is obviously not reflecting any light , does this mean we would not see the sun?
« Last Edit: 12/02/2016 09:53:54 by Thebox »


 

Offline chiralSPO

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 1875
  • Thanked: 143 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #1 on: 12/02/2016 14:49:48 »
I'm sure the sun does reflect some light from other stars, but it is minuscule compared to the light that it emits from being so hot. My uneducated guess would be that the light reflected off the sun would be about 20 orders of magnitude less than the light it emits. (I would be happy for someone else to refine this estimate)
 

Offline Colin2B

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 1915
  • Thanked: 123 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #2 on: 12/02/2016 15:04:39 »
(I would be happy for someone else to refine this estimate)
20.32853 (ish)
Although I will confess to nitpicking as I've never seen anyone using decimal OoM.
 

Offline Ethos_

  • Neilep Level Member
  • ******
  • Posts: 1277
  • Thanked: 14 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #3 on: 12/02/2016 15:28:16 »
does this mean we would not see the sun?
No...............You would still see the sun. This occurs because it's producing it's own light, "photons" which travel from it's position in space to ours in approx. 8 minutes of elapsed time. Thus, we see the light. Now, do you see the light?
 

Offline alancalverd

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 4707
  • Thanked: 153 times
  • life is too short to drink instant coffee
    • View Profile
Re: Does the Sun reflect light?
« Reply #4 on: 12/02/2016 16:27:44 »

 
Although I will confess to nitpicking as I've never seen anyone using decimal OoM.


Common logarithms are decimal orders of magnitude!
 

Offline Colin2B

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 1915
  • Thanked: 123 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #5 on: 12/02/2016 17:33:35 »
Common logarithms are decimal orders of magnitude!
That's true, didn't think of that
 

Offline Thebox

  • Neilep Level Member
  • ******
  • Posts: 3158
  • Thanked: 45 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #6 on: 12/02/2016 21:13:51 »
Thank you for the answers, that about answers that one.
 

Online Bill S

  • Neilep Level Member
  • ******
  • Posts: 1815
  • Thanked: 11 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #7 on: 13/02/2016 16:48:56 »
Quote from: Thebox
If there was only the sun, and no other matter in the universe or stars, so there was no other emitted light , so the sun is obviously not reflecting any light , does this mean we would not see the sun?

Yes. You would not be there to see it.  :)
 

Offline Ethos_

  • Neilep Level Member
  • ******
  • Posts: 1277
  • Thanked: 14 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #8 on: 13/02/2016 18:11:06 »
Quote from: Thebox
If there was only the sun, and no other matter in the universe or stars, so there was no other emitted light , so the sun is obviously not reflecting any light , does this mean we would not see the sun?

Yes. You would not be there to see it.  :)
But of course...........I fall for these trick questions every time.
 

Offline Thebox

  • Neilep Level Member
  • ******
  • Posts: 3158
  • Thanked: 45 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #9 on: 14/02/2016 09:43:04 »
Quote from: Thebox
If there was only the sun, and no other matter in the universe or stars, so there was no other emitted light , so the sun is obviously not reflecting any light , does this mean we would not see the sun?

Yes. You would not be there to see it.  :)

Lol Bill we neither see space curving but hypothetically we use it for analogies.
 

Offline evan_au

  • Neilep Level Member
  • ******
  • Posts: 4113
  • Thanked: 245 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #10 on: 14/02/2016 10:55:57 »
Quote from: Colin2B
Although I will confess to nitpicking as I've never seen anyone using decimal OoM.
The unit of "deciBel" (dB) is used for measuring sound pressure and electrical signal levels.
It is a logarithmic scale, so 24dB = 102.4
See: http://en.wikipedia.org/wiki/Decibel

In the equal-tempered musical scale, the frequencies also follow a logarithmic scale (and most other musical scales are approximately logarithmic, at least at the level of an octave). This is a non-decimal exponent, so if you were to express it as powers of 10, it would be a fractional exponent.
http://en.wikipedia.org/wiki/Scale_(music)

Other examples are the brightness of stars, which is a logarithmic scale, with a non-decimal base. It is common for astronomers to quote magnitudes with 1 decimal place.
http://en.wikipedia.org/wiki/Apparent_magnitude

In geology, the Richter scale for earthquakes is a base 10 logarithmic scale, and fractional magnitudes are often quoted.
http://en.wikipedia.org/wiki/Richter_magnitude_scale

The Volcanic Explosivity Index for supervolcanoes is logarithmic.
http://en.wikipedia.org/wiki/Volcanic_explosivity_index

Moh's scale of mineral hardness is approximately logarithmic (except diamond was way off the scale, and was arbitrarily assigned 10 on the scale).
http://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness

In chemistry, the pH scale is logarithmic, and it is easy to measure pH to one decimal place.
http://en.wikipedia.org/wiki/PH#Definition_and_measurement

Many human senses have a logarithmic response. A quantity that spans many orders of magnitude is often measured most easily with a logarithmic scale; if precision is required, a fractional order of magnitude is often used.

And back near our initial topic: X-Class Solar Flares are also categorized according to a somewhat bizarre logarithmic scale. (Lower class flares have one decimal place, but this is effectively scientific notation, rather than a decimal order of magnitude.)
http://en.wikipedia.org/wiki/Solar_flare#Classification
« Last Edit: 14/02/2016 11:47:07 by evan_au »
 

Offline Colin2B

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 1915
  • Thanked: 123 times
    • View Profile
Re: Does the Sun reflect light?
« Reply #11 on: 14/02/2016 18:30:17 »
 :) amusing Evan, nice one.
However, I stick to my original point in the context ChiralSPO used it that I have never heard anyone phrase it in decimal, always integers!
 

Offline alancalverd

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 4707
  • Thanked: 153 times
  • life is too short to drink instant coffee
    • View Profile
Re: Does the Sun reflect light?
« Reply #12 on: 14/02/2016 19:53:08 »
I've tried from time to time to promote a logarithmic risk index R

R = 10 - logP

where P is the probability of something happening, and

r = 10 - log p

where p is the probability of something happening in the next year.

Then R = 10 is inevitable, we generally legislate to control R > 5 and prohibit harmful activities where R > 7, and if r is less than 1, no living human will see it happen.

The nice thing about this scale is that it pretty well mirrors Richter and Beaufort as well as human response to perceived risk, and provides a rational basis for legislation. 

The problem is that it is really simple to understand, and will lead to mass redundancies in economics, politics and risk management.
 

Offline jeffreyH

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 3918
  • Thanked: 53 times
  • The graviton sucks
    • View Profile
Re: Does the Sun reflect light?
« Reply #13 on: 14/02/2016 20:50:10 »
I've tried from time to time to promote a logarithmic risk index R

R = 10 - logP

where P is the probability of something happening, and

r = 10 - log p

where p is the probability of something happening in the next year.

Then R = 10 is inevitable, we generally legislate to control R > 5 and prohibit harmful activities where R > 7, and if r is less than 1, no living human will see it happen.

The nice thing about this scale is that it pretty well mirrors Richter and Beaufort as well as human response to perceived risk, and provides a rational basis for legislation. 

The problem is that it is really simple to understand, and will lead to mass redundancies in economics, politics and risk management.

Let's implement it NOW!
 

The Naked Scientists Forum

Re: Does the Sun reflect light?
« Reply #13 on: 14/02/2016 20:50:10 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums