<p>Which do we receive more energy from, the CMB or starlight? (Not including the sun of course.)</p>

CC BY-SA 4.0
2023-07-16T10:37:31.453Z
I take it that you want to exclude the light from one particular nearby Type-G star, the only one easily visible during the day?
James K
CC BY-SA 4.0
2023-07-16T15:17:11.783Z
On the ground, or from space? The atmosphere is more transparent to visible light than to microwaves. (And of course it also blocks a lot of the UV from stars).
PM 2Ring
CC BY-SA 4.0
2023-07-16T15:39:07.903Z
Eg, from https://www.rfcafe.com/references/electrical/atm-absorption.htm This chart shows zenith attenuation https://www.rfcafe.com/references/electrical/images2/atmospheric-specific-attenuation-zenith-itu.gif The CMB peak is ~160 GHz.
PM 2Ring
CC BY-SA 4.0
2023-07-16T21:17:20.573Z
An answer here https://physics.stackexchange.com/questions/46838/how-many-percent-of-the-visible-light-reaching-the-earth-are-from-other-stars-th  says that the CMB is about twice as bright as the stars
James K
CC BY-SA 4.0
2023-07-17T14:49:11.743Z
The energy of the CMB dominates over starlight in the "cosmic background" — i.e. outside of the Milky Way — by an order of magnitude or more, as clarified in [this answer on physics.SE](https://physics.stackexchange.com/a/196373/70207). But if you mean here, on Earth, then starlight probably dominates.
pela
<star><cosmic-microwave-background><apparent-magnitude>
Which is brighter, starlight or the CMB?
blademan9999
# Which is brighter, starlight or the CMB?

(Asked by: username_0 on 2023-07-16)

Which do we receive more energy from, the CMB or starlight? (Not including the sun of course.)

**Tags:** star, cosmic-microwave-background, apparent-magnitude

> **Comments:**
> **username_1**: I take it that you want to exclude the light from one particular nearby Type-G star, the only one easily visible during the day?  
> **username_2**: On the ground, or from space? The atmosphere is more transparent to visible light than to microwaves. (And of course it also blocks a lot of the UV from stars).  
> **username_2**: Eg, from https://www.rfcafe.com/references/electrical/atm-absorption.htm This chart shows zenith attenuation https://www.rfcafe.com/references/electrical/images2/atmospheric-specific-attenuation-zenith-itu.gif The CMB peak is ~160 GHz.  
> **username_1**: An answer here https://physics.stackexchange.com/questions/46838/how-many-percent-of-the-visible-light-reaching-the-earth-are-from-other-stars-th  says that the CMB is about twice as bright as the stars  
> **username_3**: The energy of the CMB dominates over starlight in the "cosmic background" — i.e. outside of the Milky Way — by an order of magnitude or more, as clarified in [this answer on physics.SE](https://physics.stackexchange.com/a/196373/70207). But if you mean here, on Earth, then starlight probably dominates.  

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