<p>What lies near the center of the galaxy is of great interest and in recent times the motion of dozen(s) of stars at the center of our galaxy orbiting around Sgr A* have been measured in great detail. I show an example below. Though the field is only roughly 1 arc second wide, I don't see any non-orbiting background stars.</p>

<p>This led me to wonder...</p>

<p><strong>Question:</strong> How far have stars been seen beyond the center of the Milky Way? Though this area is opaque in visible wavelengths, infrared imaging and interferometry has led to sharp images near Sgr A*. But intentionally imaged or not, how far have objects been seen <em>beyond this distance</em> but appearing near the center of the galaxy due to geometry? Have stars been imaged clear through the center and out into the far side of the galaxy?</p>

<p>Any wavelength is fine, as long as it's image-like and the answer indicates that the object lies beyond the center of the galaxy and how that could be determined.</p>

<p><img src="https://i.sstatic.net/eXQ0F.gif" alt="homemade GIF from ESA video ESOcast 173: First Successful Test of Einstein’s General Relativity Near Supermassive Black Hole"></p>

<p><strong>above:</strong> homemade GIF from ESA video <a href="https://www.youtube.com/watch?v=if2opecmev8" rel="noreferrer">ESOcast 173: First Successful Test of Einstein’s General Relativity Near Supermassive Black Hole</a></p>

CC BY-SA 4.0
2019-07-26T04:11:12.723Z
You don't see any stationary stars, but that does not mean that they are all orbiting Sgr A*. Did you check?
ProfRob
CC BY-SA 4.0
2019-07-26T04:17:46.823Z
@RobJeffries no I didn't, good point! Okay I'll go do my "homework"...
uhoh
CC BY-SA 4.0
2020-10-11T04:28:48.360Z
I think they are pretty safe with all stars in the galaxy orbiting the core of the galaxy,  they may also be orbiting something else, but that co-orbiting system will be orbiting the core of the glaxy.
tomc
CC BY-SA 4.0
2020-10-11T07:34:46.660Z
@tomc Mass of the Milky Way: 0.8 to 1.5×10${}^{12}M_\text{☉}$, mass of SgrA*: 4.15×10${}^{6}M_\text{☉}$ so no it wouldn't be safe to say, though there's some chance that it could turn out to be true. However, the bounty is for finding out for sure, not soliciting opinions. "co-orbiting system" and "orbiting the core of the galaxy" are interesting terms, consider posting an answer which will give you room to expand on those?
uhoh
CC BY-SA 4.0
2020-07-29T22:42:17.560Z
@RobJeffries it seems I still haven't finished my homework. I probably don't know *how* to check besides asking this question.
uhoh
<observational-astronomy><milky-way><radio-astronomy><galaxy-center><infrared>
How far have stars been seen beyond the center of the Milky Way?
uhoh
# How far have stars been seen beyond the center of the Milky Way?

(Asked by: username_0 on 2019-07-26)

What lies near the center of the galaxy is of great interest and in recent times the motion of dozen(s) of stars at the center of our galaxy orbiting around Sgr A\* have been measured in great detail. I show an example below. Though the field is only roughly 1 arc second wide, I don't see any non-orbiting background stars.

This led me to wonder...

**Question:** How far have stars been seen beyond the center of the Milky Way? Though this area is opaque in visible wavelengths, infrared imaging and interferometry has led to sharp images near Sgr A\*. But intentionally imaged or not, how far have objects been seen *beyond this distance* but appearing near the center of the galaxy due to geometry? Have stars been imaged clear through the center and out into the far side of the galaxy?

Any wavelength is fine, as long as it's image-like and the answer indicates that the object lies beyond the center of the galaxy and how that could be determined.

![homemade GIF from ESA video ESOcast 173: First Successful Test of Einstein’s General Relativity Near Supermassive Black Hole](https://i.sstatic.net/eXQ0F.gif)

**above:** homemade GIF from ESA video [ESOcast 173: First Successful Test of Einstein’s General Relativity Near Supermassive Black Hole](https://www.youtube.com/watch?v=if2opecmev8)

**Tags:** observational-astronomy, milky-way, radio-astronomy, galaxy-center, infrared

> **Comments:**
> **username_1**: You don't see any stationary stars, but that does not mean that they are all orbiting Sgr A*. Did you check?  
> **username_0**: @RobJeffries no I didn't, good point! Okay I'll go do my "homework"...  
> **username_0**: @RobJeffries it seems I still haven't finished my homework. I probably don't know *how* to check besides asking this question.  
> **username_2**: I think they are pretty safe with all stars in the galaxy orbiting the core of the galaxy,  they may also be orbiting something else, but that co-orbiting system will be orbiting the core of the glaxy.  
> **username_0**: @username_2 Mass of the Milky Way: 0.8 to 1.5×10${}^{12}M_\text{☉}$, mass of SgrA*: 4.15×10${}^{6}M_\text{☉}$ so no it wouldn't be safe to say, though there's some chance that it could turn out to be true. However, the bounty is for finding out for sure, not soliciting opinions. "co-orbiting system" and "orbiting the core of the galaxy" are interesting terms, consider posting an answer which will give you room to expand on those?  

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## 0 answers

