<h1>About 670,000 miles per hour</h1>
<p>Thanks to blueshifting, we have been able to pin the velocity of the Andromeda Galaxy at about <a href="https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_collision#Certainty:%7E:text=Way%20at%20about-,300%20km/s" rel="nofollow noreferrer">300 kilometers per <strong>SECOND</strong></a>, which when converted, yields a approximate value of about 670,000 mph.</p>

CC BY-SA 4.0
2023-11-26T15:44:59.617Z
2023-11-26T15:44:59.617Z
Arcturus
<p>Apparently Andromeda is going to get here in 5 billion years and is 2.5 million light years away. I tried to work this out myself but I'm not sure I believe the answer..</p>

CC BY-SA 4.0
2023-11-26T11:25:29.617Z
Please show your work.
Nilay Ghosh
CC BY-SA 4.0
2023-11-26T11:27:23.777Z
As I am sure my work is probably wrong I would rather not...
Michael Mcgarry
CC BY-SA 4.0
2023-11-26T11:44:07.543Z
See https://physics.stackexchange.com/q/26745/123208 & https://iopscience.iop.org/article/10.1088/0004-637X/753/1/8
PM 2Ring
CC BY-SA 4.0
2023-11-26T12:21:44.403Z
Cheers. I am glad I didn't show my working. I was out by a factor of ten.
Michael Mcgarry
CC BY-SA 4.0
2023-11-26T12:42:12.660Z
Please show your work even if it wrong. Showing your work acknowledges that you have shown effort. The fact that you were wrong is the reason you asked this question: https://astronomy.meta.stackexchange.com/a/429/35206
Nilay Ghosh
CC BY-SA 4.0
2023-11-26T12:42:55.957Z
It's not bad to show something where there is a flaw in the math. It's worse to not - and not learn from ones own mistakes, and repeat them. The aim of this site is that everyone can learn from questions. Also especially in astronomy and astrophyics: a factor of 10 is sometimes easy to explain when starting with different assumptions about the initial conditions, making neither calculation wrong.
planetmaker
<galaxy><amateur-observing>
How fast is Andromeda approaching in miles per hour
Michael Mcgarry
# How fast is Andromeda approaching in miles per hour

(Asked by: username_0 on 2023-11-26)

Apparently Andromeda is going to get here in 5 billion years and is 2.5 million light years away. I tried to work this out myself but I'm not sure I believe the answer..

**Tags:** galaxy, amateur-observing

> **Comments:**
> **username_1**: Please show your work.  
> **username_0**: As I am sure my work is probably wrong I would rather not...  
> **username_2**: See https://physics.stackexchange.com/q/26745/123208 & https://iopscience.iop.org/article/10.1088/0004-637X/753/1/8  
> **username_0**: Cheers. I am glad I didn't show my working. I was out by a factor of ten.  
> **username_1**: Please show your work even if it wrong. Showing your work acknowledges that you have shown effort. The fact that you were wrong is the reason you asked this question: https://astronomy.meta.stackexchange.com/a/429/35206  
> **username_3**: It's not bad to show something where there is a flaw in the math. It's worse to not - and not learn from ones own mistakes, and repeat them. The aim of this site is that everyone can learn from questions. Also especially in astronomy and astrophyics: a factor of 10 is sometimes easy to explain when starting with different assumptions about the initial conditions, making neither calculation wrong.  

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## 1 answers

### Answer by username_4 on 2023-11-26. Score: 2

# About 670,000 miles per hour

Thanks to blueshifting, we have been able to pin the velocity of the Andromeda Galaxy at about [300 kilometers per **SECOND**](https://en.wikipedia.org/wiki/Andromeda%E2%80%93Milky_Way_collision#Certainty:%7E:text=Way%20at%20about-,300%20km/s), which when converted, yields a approximate value of about 670,000 mph.


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