What do barred spiral (SB) galaxies look like?

On Tue, 11 May 1999, Frida wrote:

> How come galaxy type SB looks like a "pipe"?

Hello,

SB galaxies are spiral galaxies with a bar in their centers. The reasons
why some spiral galxies have bars and some do not are not fully
understood. It may be that a nearby galaxy's gravity causes the bar to form,
or it may be that the disk of a spiral galaxy is unstable and naturally
forms a bar at some times in its life. However, bars are very important
in studying galaxies, because a bar can funnel gas and dust into the
center of a galaxy, causing stars to form, and possible feeding the giant
black holes that live in the centers of galaxies. Also, many astronomers
now believe that the Milky Way has a bar, so understanding bars is
crucial to understanding our own galaxy.

Thanks for writing!

Sincerely,
Kurtis Williams

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