NGC 3718, extra galaxies? (APOD 31 Aug 2006)

jmb · Post by **jmb** » Thu Aug 31, 2006 6:17 pm

Hi,

In the text it links to details of the scene (1, 2 and 3) but they are mirrored. Why is that? Which one is correct?

thanks!

craterchains · Post by **craterchains** » Sat Sep 02, 2006 1:52 am

The other one is the correct one.

Norval

Planet Claire · Post by **Planet Claire** » Sun Sep 03, 2006 9:08 pm

Hi all,

This is my first time posting.

I have a thought about NGC 3718 2006 August 31: Extra Galaxies.
I am not an astrophysicist, however to me this galaxy looks like two galaxies collided and is now reforming to one or separating.

Could someone commit on this.,
Thank you.

astro_uk · Post by **astro_uk** » Mon Sep 04, 2006 4:50 pm

I don't think that two galaxies collided to form NGC 3718 but from the information available it does seem as if it has been tidally disrupted by the other spiral nearby. This type of thing is fairly common, even if the galaxies dont physically hit their gravity can cause damage in each other from a fairly large distance. The Milky Way is tearing apart one of its own dwarf satellite galaxies as we speak.

Check out here for a lot more example of interacting galaxies.

http://www.astr.ua.edu/pairs2.html

This APOD shows a nice example of what happens when two galaxies do actually impact. (in reality the stars in each galaxy just pass each other, but the gravity still screws up the spiral structure)

http://apod.nasa.gov/apod/ap970224.html

Of course if they impact more slowly and are gravitationally bound they tend to merge to form large elliptical galaxies.

Planet Claire · Post by **Planet Claire** » Mon Sep 04, 2006 9:11 pm

Thanks for your response. 8)

Starship Asterisk*

NGC 3718, extra galaxies? (APOD 31 Aug 2006)

NGC 3718, extra galaxies? (APOD 31 Aug 2006)

NGC 3718 (APOD 31 Aug 2006)