<p>I expect that all the itelescope.net instruments work at visible wavelengths. Therefore you have no chance at all to image the stars around Sgr A*, since it is behind about 25-30 magnitudes of optical extinction, caused by dust between us and the Galactic centre.</p>

<p>The published images you have seen were taken by large telescopes working with adaptive optics in the near-infrared (wavelengths longer than 1.5 <span class="math-container">$\mu$</span>m). At these longer wavelengths the extinction caused by dust is only 2-3 magnitudes.</p>

CC BY-SA 4.0
2019-08-30T08:45:47.133Z
Actually it appears that some of the telescopes do have extended red sensitivity: https://support.itelescope.net/support/solutions/articles/231915-telescope-17: T17 is a Science Platform. Normally used for Science Missions, Deep Photometry, Narrowband and 'Extended Red' light IR imaging. It is equipped with a FLI ProLine E2V CCD47-10-1-109 CCD. that has 'extended red sensitivity' when compared to standard CCD’s. Giving it an almost 'Near Infrared' mission profile.
Nickpick
CC BY-SA 4.0
2019-08-30T10:02:41.777Z
@Nickpick It is still an optical CCD and as such has no sensitivity at wavelengths beyond the 1.1 $\mu$m that is required for a photon to excite an electron across the Si band gap. With this CCD/instrument the best you could do is observe through the broad band I filter, but the extinction to the GC is still about 15 magnitudes at this wavelength.
ProfRob
CC BY-SA 4.0
2019-08-30T13:17:04.530Z
Are there any publicly available telescope that offer that sensitivity? If not, is there any raw data available that I could download?
Nickpick
CC BY-SA 4.0
2019-08-30T13:21:05.823Z
@Nickpick That sounds like a good, new question.
ProfRob
CC BY-SA 4.0
2019-08-30T13:22:51.983Z
here we go: https://astronomy.stackexchange.com/questions/33204/raw-data-to-observe-sgr-a
Nickpick
CC BY-SA 4.0
2019-08-29T16:01:05.997Z
2019-08-30T07:15:45.123Z
2019-08-30T07:15:45.123Z
ProfRob
<p>I've been experimenting with <a href="https://www.itelescope.net/" rel="nofollow noreferrer">itelescope.net</a> and tried to observe Sgr A*.</p>
<p>I was wondering if there are any suggestions as to how I can best observe the surrounding stars?</p>

<observational-astronomy><telescope><amateur-observing><photography><sagittarius-a>
How can I observe Sgr A* with itelescope.net
Nickpick
# How can I observe Sgr A* with itelescope.net

(Asked by: username_0 on 2019-08-29)

I've been experimenting with [itelescope.net](https://www.itelescope.net/) and tried to observe Sgr A\*.

I was wondering if there are any suggestions as to how I can best observe the surrounding stars?

**Tags:** observational-astronomy, telescope, amateur-observing, photography, sagittarius-a

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## 1 answers

### Answer by username_1 on 2019-08-29. Score: 13 | Accepted answer

I expect that all the itelescope.net instruments work at visible wavelengths. Therefore you have no chance at all to image the stars around Sgr A\*, since it is behind about 25-30 magnitudes of optical extinction, caused by dust between us and the Galactic centre.

The published images you have seen were taken by large telescopes working with adaptive optics in the near-infrared (wavelengths longer than 1.5 $\mu$m). At these longer wavelengths the extinction caused by dust is only 2-3 magnitudes.

> **Comments:**
> **username_0**: Actually it appears that some of the telescopes do have extended red sensitivity: https://support.itelescope.net/support/solutions/articles/231915-telescope-17: T17 is a Science Platform. Normally used for Science Missions, Deep Photometry, Narrowband and 'Extended Red' light IR imaging. It is equipped with a FLI ProLine E2V CCD47-10-1-109 CCD. that has 'extended red sensitivity' when compared to standard CCD’s. Giving it an almost 'Near Infrared' mission profile.  
> **username_1**: @Nickpick It is still an optical CCD and as such has no sensitivity at wavelengths beyond the 1.1 $\mu$m that is required for a photon to excite an electron across the Si band gap. With this CCD/instrument the best you could do is observe through the broad band I filter, but the extinction to the GC is still about 15 magnitudes at this wavelength.  
> **username_0**: Are there any publicly available telescope that offer that sensitivity? If not, is there any raw data available that I could download?  
> **username_1**: @Nickpick That sounds like a good, new question.  
> **username_0**: here we go: https://astronomy.stackexchange.com/questions/33204/raw-data-to-observe-sgr-a  

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