<p>Yes, of course. Many, many examples. Telescopes work in the infrared, far-infrared and there are even samples of galaxies that are selected on the basis of their mm emission.</p>
<p>The most distant galaxies detected now have redshifts of 10 or more (see for example <a href="https://astronomy.stackexchange.com/a/8344/2531">here</a>). This means the wavelength of their light has been stretched by a factor <span class="math-container">$1+z$</span> - i.e. by a factor of 11. Thus light in the visible range, say 500nm, now appears at wavelength of 5.5 microns, in the infrared.</p>
<p>Telescopes that work in this range include the Spitzer space telescope; the James Webb Space Telescope and many ground-based telescopes. Observations of highly redshifted galaxies are routinely made at infrared wavelengths on telescopes all around the world.</p>
<p>Galaxies are also detected in the far infrared by the Herschel satellite or at mm (getting on for microwave) wavelengths by JCMT or the ALMA telecope.</p>

CC BY-SA 4.0
2014-12-03T20:00:30.553Z
2023-01-17T16:25:51.957Z
2023-01-17T16:25:51.957Z
ProfRob
<p>According to <a href="https://astronomy.stackexchange.com/a/8118/1142">this</a> answer it is possible for galaxies' light to move beyond the visible frequencies due to redshift:</p>
<blockquote>
<p>It is possible that eventually the light from them could move into the infrared and even
the microwave in extreme cases</p>
</blockquote>
<p>Could this have already happened?  Have we already looked for it?  Is there a telescope with the instrumentation to detect galaxies' 'light' at these wavelengths?</p>

CC BY-SA 3.0
2014-12-03T21:41:58.417Z
If the visible light they emit is shifted into the infrared, then any UV they emit will be shifted into the visible.
Keith Thompson
CC BY-SA 3.0
2014-12-04T07:34:25.427Z
@KeithThompson That is true of course, though usually the UV light is heavily attenuated by dust absorption. This is the principle behind finding high redshift galaxies via the "Lyman break" technique.
ProfRob
<observational-astronomy><redshift><deep-sky-observing>
Have we detected galaxies which have red-shifted beyond the visible light range?
Tracy Cramer
# Have we detected galaxies which have red-shifted beyond the visible light range?

(Asked by: username_0 on 2014-12-03)

According to [this](https://astronomy.stackexchange.com/a/8118/1142) answer it is possible for galaxies' light to move beyond the visible frequencies due to redshift:

> It is possible that eventually the light from them could move into the infrared and even
> the microwave in extreme cases

Could this have already happened? Have we already looked for it? Is there a telescope with the instrumentation to detect galaxies' 'light' at these wavelengths?

**Tags:** observational-astronomy, redshift, deep-sky-observing

> **Comments:**
> **username_1**: If the visible light they emit is shifted into the infrared, then any UV they emit will be shifted into the visible.  
> **username_2**: @KeithThompson That is true of course, though usually the UV light is heavily attenuated by dust absorption. This is the principle behind finding high redshift galaxies via the "Lyman break" technique.  

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## 1 answers

### Answer by username_2 on 2014-12-03. Score: 9 | Accepted answer

Yes, of course. Many, many examples. Telescopes work in the infrared, far-infrared and there are even samples of galaxies that are selected on the basis of their mm emission.

The most distant galaxies detected now have redshifts of 10 or more (see for example [here](https://astronomy.stackexchange.com/a/8344/2531)). This means the wavelength of their light has been stretched by a factor $1+z$ - i.e. by a factor of 11. Thus light in the visible range, say 500nm, now appears at wavelength of 5.5 microns, in the infrared.

Telescopes that work in this range include the Spitzer space telescope; the James Webb Space Telescope and many ground-based telescopes. Observations of highly redshifted galaxies are routinely made at infrared wavelengths on telescopes all around the world.

Galaxies are also detected in the far infrared by the Herschel satellite or at mm (getting on for microwave) wavelengths by JCMT or the ALMA telecope.


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