An unbarred spiral galaxyAstronomy Pictures

(accessed 18 April 2010) is a type of

spiral galaxy Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''barred spiral galaxy. It is designated with an SA in the galaxy morphological classification scheme. Barless spiral galaxies are one of three general types of spiral galaxies under the ''de Vaucouleurs system'' classification system, the other two being intermediate spiral galaxy and barred spiral galaxy. Under the ''Hubble tuning fork'', it is one of two general types of spiral galaxy, the other being barred spirals.

Grades

Unbarred lenticular galaxy

An unbarred lenticular galaxy is a

lenticular Lenticular is an adjective often relating to lenses. It may refer to: * A term used with two meanings in botany: see * Lenticular cloud, a lens-shaped cloud * Lenticular galaxy, a lens-shaped galaxy * Lenticular (geology), adjective describing a ...

version of an unbarred spiral galaxy. They have the

Hubble type The Hubble sequence is a morphological classification scheme for galaxies invented by Edwin Hubble in 1926. It is often colloquially known as the Hubble tuning-fork diagram because the shape in which it is traditionally represented resembles a t ...

of SA0. An example of this is the galaxy,

AM 0644-741 AM 0644-741, also known as the Lindsay-Shapley Ring, is an unbarred lenticular galaxy, and a ring galaxy, which is 300 million light-years away in the southern constellation Volans. Properties Formation The yellowish nucleus was once the ...

. For other examples see :Unbarred lenticular galaxies.

References

* Galaxy morphological types {{Spiral-galaxy-stub