A blue elliptical galaxy

• by Thongduc3885

  So as far as I know, most if not all elliptical galaxies is very old and have stopped making new stars so they have a yellow color but this elliptical galaxy is all blue. Is there any explanation for this?

  Posted October 13, 2017 2:36 PM

• by NGC3314 scientist

  Some ellipticals do still manage to have enough gas to maintain significant star formation (which many people recognized only after Galaxy Zoo Classic, along with their counterparts the red spirals). They are mostly found in unusually sparse environments for ellipticals (which evidently makes it easier to keep the cold gas). There remains a lot of room to find out more about what makes these different.

  Posted October 13, 2017 2:57 PM

• by JeanTate

  And it may not be a classical elliptical at all! 😮

  It's SDSS J114638.39-012819.8, and its fracDeV_g, _r, and _i values are 0.33, 0.36, 0.40 (respectively). Which strongly hints at what your eyes may tell you anyway when peering at the image ... this galaxy very likely has a disk and a bulge, making it not an elliptical at all, but either a lenticular or a spiral (ellipticals do not have disks made of stars).

  Maybe a higher resolution image would show that it's clearly a spiral (i.e. we could clearly see at least one spiral arm)?

  Posted October 13, 2017 3:26 PM

• by ElisabethB moderator

  I wouldn't classify this one as an elliptical either . I'd go for a fuzzy barred (maybe spiral) galaxy..

  Posted October 13, 2017 4:44 PM

• by Budgieye moderator

  

  Posted October 13, 2017 6:15 PM