<p>The Solar System moving through intergalactic space would have no impact on life. However, in order for the sun to be ejected out of the Galaxy, a very close encounter with a stellar mass object would be necessary. That would likely have a huge negative impact on life on earth, at a minimum perturbing many objects in the Oort Cloud into the inner solar syste. At the other end of the spectrum, the orbit of earth could be significantly altered or the earth could even be ejected from the solar system, depending on the geometry of the encounter. </p>

CC BY-SA 3.0
2016-04-10T10:12:02.280Z
A simple collision with another star cannot impart additional kinetic energy to the Sun.
ProfRob
CC BY-SA 3.0
2016-04-10T16:29:09.487Z
A stellar collision is not what I was referring to.
Dave
CC BY-SA 3.0
2016-04-10T16:38:17.063Z
Substitute the words "close encounter with a stellar mass object". There would have to be a third body involved - i.e. an interaction with a close binary. I do not think this is the way that stars are ejected in a galaxy collision.
ProfRob
CC BY-SA 3.0
2016-04-09T22:18:11.800Z
2016-04-09T22:18:11.800Z
Dave
<p>I can think of two ways this benefits life.</p>

<ul>
<li>Less chance of a passing star disrupting our Oort Cloud and sending
deadly comets crashing into the Earth.</li>
<li>Less chance of nearby supernova destroying our ozone layer.</li>
</ul>

<p>On the other hand, if our Solar System passes near <a href="https://en.wikipedia.org/wiki/Astrophysical_jet#Relativistic_jet" rel="nofollow">a relativistic jet</a> emanating from the central black hole of a galaxy, Earth will get hit with high speed particles that will disrupt the magnetosphere and ozone layer. Definitely not good for any life on Earth at that time.</p>

<p>Getting ejected from the galaxy also means there is less chance of future humans exploring the galaxy by hopping to nearby stars. We'd only have our solar system to explore and colonize. There would not be another star system within a hundred thousand light years.</p>

CC BY-SA 3.0
2016-03-30T15:57:51.530Z
2016-04-09T23:08:21.780Z
2016-04-09T23:08:21.780Z
RichS
<p>I was reading about the impending collision of our galaxy with the Andromeda galaxy, and learned that there is a small possibility that our solar system could be ejected during the collision. </p>

<p>Assuming that orbits within our solar system remain unchanged (it is ejected as a whole), would floating in intergalactic space cause any significant changes in the living conditions on earth? </p>

CC BY-SA 3.0
2016-03-23T20:00:00.097Z
There's actually a very good answer to this on the physics forum http://physics.stackexchange.com/questions/112887/what-will-happen-if-the-solar-system-leaves-the-milky-way-galaxy, it covers lots of angles including the pros and cons of leaving the galaxy.
Dean
CC BY-SA 3.0
2016-03-24T16:34:01.863Z
Oort cloud included, or not?
Wayfaring Stranger
CC BY-SA 3.0
2016-03-24T17:02:49.160Z
I assume that if the oort cloud was disturbed that would mean a significant increase in the chances of cataclysmic impact, but I think that the oort cloud would be considered a set of "orbits within our solar system", since its objects orbit our sun- right?
Andrew
CC BY-SA 3.0
2016-03-24T19:59:01.507Z
@Andrew Right, but if the disturbing star comes in from, say, the left side, then Oort objects on the right side aren't going to be nearly so disturbed. Depending on geometry, we could totally lose some of the outer planets as well.
Wayfaring Stranger
CC BY-SA 3.0
2016-03-25T01:05:16.693Z
If your question is a thought experiment where you take the solar system as it is today and "beam it" unaltered (Oort cloud and all) to a location well outside the Milky Way, then I think it would be better (lower density of radiation and less chance of an object perturbing the Oort cloud and hurling something our way). It would be sad not to have a sky full of stars, with the dream of traveling to one, but the Milky Way would be a sight to behold. Of course, the Earth will be uninhabitable long before the Milky Way and Andromeda collide.
Jack R. Woods
CC BY-SA 3.0
2016-03-25T01:52:16.453Z
@Jackrwoods Imagine that! A spiral galaxy hovering over the horizon.
Andrew
CC BY-SA 3.0
2016-03-25T18:23:18.017Z
The only realistic way to eject stars from a galaxy is by close encounters with a massive object (ideally a supermassive black hole - SMBH), which would certainly destroy the Solar system (unbind most planets) if this happens to the Sun (when it collides with M31s' SMBH in the merger).
Walter
CC BY-SA 3.0
2016-03-26T00:03:15.197Z
I doubt these tails result strictly from SMBH: http://apod.nasa.gov/apod/ap040612.html http://apod.nasa.gov/apod/ap121108.html Still it seems inclusion in a long tail could easily mess with Oort cloud structure as well.
Wayfaring Stranger
CC BY-SA 3.0
2016-03-30T16:57:48.333Z
(Controversial?) [physics professor Svensmark](https://en.wikipedia.org/wiki/Henrik_Svensmark#Debate_and_controversy) has suggested that Earth might undergo climate changes on a galactic scale as it orbits the Milky Way. Different regions have different intensity of stellar winds which affect the magnetosphere of Earth and the formation of clouds. A vagabond Solar System would not have that. *(I just love the idea of us having a galactic weather!)*
LocalFluff
CC BY-SA 3.0
2016-03-31T17:01:44.827Z
For a very long time, we would have a wonderful view of a galaxy merger.
eshaya
<life><intergalactic-space>
Would being ejected from the Milky Way Galaxy have any major impact on life on Earth?
Andrew
# Would being ejected from the Milky Way Galaxy have any major impact on life on Earth?

(Asked by: username_0 on 2016-03-23)

I was reading about the impending collision of our galaxy with the Andromeda galaxy, and learned that there is a small possibility that our solar system could be ejected during the collision.

Assuming that orbits within our solar system remain unchanged (it is ejected as a whole), would floating in intergalactic space cause any significant changes in the living conditions on earth?

**Tags:** life, intergalactic-space
> **Comments:**
> **username_1**: There's actually a very good answer to this on the physics forum http://physics.stackexchange.com/questions/112887/what-will-happen-if-the-solar-system-leaves-the-milky-way-galaxy, it covers lots of angles including the pros and cons of leaving the galaxy.  
> **username_2**: Oort cloud included, or not?  
> **username_0**: I assume that if the oort cloud was disturbed that would mean a significant increase in the chances of cataclysmic impact, but I think that the oort cloud would be considered a set of "orbits within our solar system", since its objects orbit our sun- right?  
> **username_2**: @Andrew Right, but if the disturbing star comes in from, say, the left side, then Oort objects on the right side aren't going to be nearly so disturbed. Depending on geometry, we could totally lose some of the outer planets as well.  
> **username_3**: If your question is a thought experiment where you take the solar system as it is today and "beam it" unaltered (Oort cloud and all) to a location well outside the Milky Way, then I think it would be better (lower density of radiation and less chance of an object perturbing the Oort cloud and hurling something our way). It would be sad not to have a sky full of stars, with the dream of traveling to one, but the Milky Way would be a sight to behold. Of course, the Earth will be uninhabitable long before the Milky Way and Andromeda collide.  
> **username_0**: @Jackrwoods Imagine that! A spiral galaxy hovering over the horizon.  
> **username_4**: The only realistic way to eject stars from a galaxy is by close encounters with a massive object (ideally a supermassive black hole - SMBH), which would certainly destroy the Solar system (unbind most planets) if this happens to the Sun (when it collides with M31s' SMBH in the merger).  
> **username_2**: I doubt these tails result strictly from SMBH: http://apod.nasa.gov/apod/ap040612.html http://apod.nasa.gov/apod/ap121108.html Still it seems inclusion in a long tail could easily mess with Oort cloud structure as well.  
> **username_5**: (Controversial?) [physics professor Svensmark](https://en.wikipedia.org/wiki/Henrik_Svensmark#Debate_and_controversy) has suggested that Earth might undergo climate changes on a galactic scale as it orbits the Milky Way. Different regions have different intensity of stellar winds which affect the magnetosphere of Earth and the formation of clouds. A vagabond Solar System would not have that. *(I just love the idea of us having a galactic weather!)*  
> **username_6**: For a very long time, we would have a wonderful view of a galaxy merger.  

---

## 2 answers

### Answer by username_7 on 2016-04-09. Score: 0

The Solar System moving through intergalactic space would have no impact on life. However, in order for the sun to be ejected out of the Galaxy, a very close encounter with a stellar mass object would be necessary. That would likely have a huge negative impact on life on earth, at a minimum perturbing many objects in the Oort Cloud into the inner solar syste. At the other end of the spectrum, the orbit of earth could be significantly altered or the earth could even be ejected from the solar system, depending on the geometry of the encounter.

> **Comments:**
> **username_8**: A simple collision with another star cannot impart additional kinetic energy to the Sun.  
> **username_7**: A stellar collision is not what I was referring to.  
> **username_8**: Substitute the words "close encounter with a stellar mass object". There would have to be a third body involved - i.e. an interaction with a close binary. I do not think this is the way that stars are ejected in a galaxy collision.  

---

### Answer by username_9 on 2016-03-30. Score: 0

I can think of two ways this benefits life.

* Less chance of a passing star disrupting our Oort Cloud and sending
  deadly comets crashing into the Earth.
* Less chance of nearby supernova destroying our ozone layer.

On the other hand, if our Solar System passes near [a relativistic jet](https://en.wikipedia.org/wiki/Astrophysical_jet#Relativistic_jet) emanating from the central black hole of a galaxy, Earth will get hit with high speed particles that will disrupt the magnetosphere and ozone layer. Definitely not good for any life on Earth at that time.

Getting ejected from the galaxy also means there is less chance of future humans exploring the galaxy by hopping to nearby stars. We'd only have our solar system to explore and colonize. There would not be another star system within a hundred thousand light years.


---

