Galactic collisions.

[Grump Martian]

Below is a link to an explanation on how a smaller galaxy The Sagittarius Dwarf has periodically collided with the Milky Way galaxy. I became aware of this after watching an episode of The Universe with Brian Cox. He explained that a collision between two galaxies would not result in the destruction of solar systems as there are emense gaps between the stars. The Saggitarius galaxy circles the Milky Way and has collided three times over millenia. This has left a trail of debris or stars. The first collision several billion years ago. Brian knows this as he was there to withness the first collision.

I am now left scratching my head. I tell you why, I always thought that the band of light arching across the zenith of the night sky in the Summer as seen from a lovely dark sky was our home Solar system's galactic spiral arm. But I now as a result of watching the programme I think that it is the trail left by the collision. Or am I wrong and now confused. Please help a lost inhabitant of the outer reaches of the Milky Way.

 

https://www.esa.int/Science_Exploration/Space_Science/Gaia/Galactic_crash_may_have_triggered_Solar_System_formation

[Chaz2b]

In that “ this has left a trail of debris or STARS”, what could possibly stop a star?! The forces would be…….astronomical !! As it mentions, there are emense gaps between stars, so what would stop a star? Did someone say, “ here’s your stop, time to get off your galactic journey” or what!

We are allowed to take this with a pinch of salt, as it states MAY HAVE.

chaz

[michael8554]

"Brian knows this as he was there to withness the first collision."

That's an unwarranted gibe at his apparently youthful appearance  😆

He actually witnessed the "Big Bang".

Maybe even caused it.......... ?

Michael

 

Edited March 11, 2023 by michael8554

[Paz]

The band of light you describe across the sky I think would be our galaxy, I don't think any trail of stars relating to those collisions would be visible naked eye. I assume they identy the trail from huge scientific scopes and/or estimating then position and motion of many stars and using computers to find patterns that indicate such associations.

The dwarf galaxy is I think PGC4689212 and in terms of easily visible things associated with it M54 is a globular cluster that is thought to be associated with it and is right in the middle from our perspective.