An example of a spiral galaxy, Messier 77 (also known as NGC 1068) Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae [1] and, as such, form part of the Hubble sequence.Most spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge.

2018年11月19日 · Spiral galaxies are thought to evolve into elliptical galaxies as the spirals get older. But it's unclear how common elliptical galaxies are as they're made up of older, dimmer stars, and are more ...

2025年1月17日 · a galaxy exhibiting a central nucleus or barred structure from which extend curved arms of higher luminosity —called also spiral nebula… See the full definition Menu Toggle

A famous spiral galaxy, the Pinwheel Galaxy (also known as Messier 101 or NGC 5457) A barred spiral galaxy, NGC 1300 A spiral galaxy is a kind of galaxy that looks like a flat, slowly rotating disk with a bulge in the centre, and spiral patterns extending outward from the bulge. It contains stars, gas, dust, dark matter and a supermassive black hole at its centre.

2024年4月30日 · Andromeda is a large, bright spiral galaxy with well-defined spiral arms and a prominent central bulge. Another notable example is the Whirlpool Galaxy, also known as M51. This galaxy is located about 23 million light-years away and is famous for its striking spiral arms and interactions with a smaller companion galaxy.

In a spiral galaxy, the stars, gas and dust are gathered in spiral arms that spread outward from the galaxy's center. Spiral galaxys are divided into three main types depending on how tightly wound their spiral arms are: Sa, Sb and Sc. Sa galaxies have very tightly wound arms around a larger central nucleus. Sc galaxies have very loosely wound ...

A spiral galaxy typically has a rotating disc with spiral ‘arms’ that curve out from a dense central region. The Milky Way is a spiral galaxy. Four classes are used to classify galaxies: spiral; barred spiral; elliptical and irregular. Spiral galaxies have a complex structure: a dense central bulge lies at the centre of a rotating disc ...

2024年12月1日 · A spiral galaxy is a type of galaxy characterized by its distinctive spiral arm structure. Spiral galaxies consist of a rotating disk containing stars, gas, and dust, with a central bulge or bar. The spiral arms of these galaxies extend outward from the center, creating a pattern visible across vast cosmic distances. Spiral galaxies are...

2020年1月8日 · Spiral galaxy type B – abbreviation Sb – have a moderately-sized central bulge and moderately-well-defined spiral arms. 3. Spiral Galaxy type C – abbreviation Sc – small central bulge as well as narrow and well-defined central arms. They contain about 15% gas and dust. 4. Barred spiral galaxy type A – abbreviation SBa – they feature ...

Term and definition status: This term and its definition have been approved by a research astronomer and a teacher. ... In addition, M96, a spiral galaxy, can be seen as a fuzzy object using a small telescope, and Messier 105, an elliptical galaxy. Each of these objects are labelled on the map as red ellipses.