possible 2 axis

i think this galaxy could have 2 axis

Posted July 23, 2017 2:53 PM

by Budgieye moderator

I think you could be right. Let's tag it with #X-shaped in case anyone want to find it. Sometime the Illustris scientists look through the posts concerning their simulated galaxies.

Posted July 23, 2017 7:46 PM

by leeskelvin scientist

This is indeed an interesting system. To me it looks like it has a primary axis closer to 2 o'clock with two spots of blue star-formation ongoing at the tips of a very thin disk, and a secondary axis closer to 3 o'clock consisting of an older, red stellar population. As the blue star-forming regions seem to line up with the apparent axis within the centre of the galaxy, I label this as the primary axis.

I suspect the secondary axis is in fact a stellar stream, and may have been formed via a minor-merger with a low-mass quiescent (non-star-forming) satellite galaxy. It reminds me somewhat of NGC 5907 (https://apod.nasa.gov/apod/ap080619.html), but with the dwarf merger here taking place much closer to the galaxy plane. As this is simulated data, scientists from the Illustris team should be able to catalogue the formation of this galaxy and find out exactly what's going on!

Posted July 24, 2017 4:55 PM