Editing Galactic bulge (section)

== Boxy/peanut bulge for edge-on galaxies ==
{{Multiple image
| direction         = horizontal
| total_width       = 400
| image1            = Exposing the Milky Way's "X".jpg
| caption1          = The X-shape of the bulge of the Milky Way.
| image2            = NGC 1175 - Flickr - geckzilla.png
| caption2          = The prominent X-shape of the bulge of [[NGC 1175]] as seen by Hubble.
}}
Edge-on galaxies can sometimes have a boxy/peanut bulge with an X-shape. The boxy nature of the Milky Way bulge was revealed by the [[Cosmic Background Explorer|COBE]] satellite and later confirmed with the [[VVV Survey|VVV survey]] with the help of [[red clump]] stars. The VVV survey also found two overlapping populations of red clump stars and an X-shape of the bulge. The [[Wide-field Infrared Survey Explorer|WISE]] satellite later confirmed the X-shape of the bulge. The X-shape makes up 45% of the mass of the bulge in the Milky Way.<ref>{{Cite journal |last1=Ness |first1=Melissa |last2=Lang |first2=Dustin |date=2016-07-01 |title=The X-shaped Bulge of the Milky Way Revealed by WISE |journal=The Astronomical Journal |volume=152 |issue=1 |pages=14 |doi=10.3847/0004-6256/152/1/14 |issn=0004-6256|arxiv=1603.00026 |bibcode=2016AJ....152...14N |doi-access=free }}</ref> The boxy/peanut bulges are in fact the [[Barred spiral galaxy|bar]] of a galaxy seen edge-on.<ref>{{Cite journal |last=Athanassoula |first=E. |date=2005-04-01 |title=On the nature of bulges in general and of box/peanut bulges in particular: input from N-body simulations |journal=Monthly Notices of the Royal Astronomical Society |volume=358 |issue=4 |pages=1477–1488 |doi=10.1111/j.1365-2966.2005.08872.x |bibcode=2005MNRAS.358.1477A |issn=0035-8711|doi-access=free |arxiv=astro-ph/0502316 }}</ref> Other edge-on galaxies can also show a boxy/peanut bar sometimes with an X-shape.