Question:

How many light years away across is the milky way galaxy?

Answer:

The diameter of the Milky Way is 90,000 light years. Thanks for asking AnswerParty!

More Info:


light years

A light-year (symbol: ly) is an astronomical unit of length equal to just under 10 trillion kilometres (or about 6 trillion miles). As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year.

The light-year is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist and popular science publications. The preferred unit in professional astrometry is the parsec (symbol: pc, approximately 3.26 light-years), because it can be more easily derived from, and compared with, observational data.

Astronomy

Extragalactic astronomy is the branch of astronomy concerned with objects outside our own Milky Way galaxy. In other words, it is the study of all astronomical objects which are not covered by galactic astronomy, the next level of galactic astronomy.

As instrumentation has improved, more distant objects can now be examined in detail. It is therefore useful to sub-divide this branch into Near-Extragalactic Astronomy and Far-Extragalactic Astronomy. The former deals with objects such as the galaxies of our Local Group, which are close enough to allow very detailed analyses of their contents (e.g. supernova remnants, stellar associations). The latter describes the study of objects sufficiently far away that only the brightest phenomena are observable.


Local Group

The Local Group is the group of galaxies that includes the Milky Way among others. It comprises more than 54 galaxies, counting dwarf galaxies. Its gravitational center is located somewhere between Milky Way and Andromeda Galaxy. The Local Group covers a diameter of 10 megalight-years (3.1 megaparsecs) (see 1 E+23 m for distance comparisons) and has a binary (dumbbell) distribution. The group is estimated to have a total mass of 1.29±0.14 ×1012 M and has a velocity dispersion of 61±8 km/s. The group itself is part of the Virgo Supercluster (i.e. the Local Supercluster).

The two most massive members of the group are Milky Way and Andromeda Galaxy. These two spiral galaxies each have a system of satellite galaxies.


Physical cosmology

Physical cosmology, as a branch of astronomy, is the study of the largest-scale structures and dynamics of the Universe and is concerned with fundamental questions about its formation and evolution. For most of human history, it was a branch of metaphysics and religion. Cosmology as a science originated with the Copernican principle, which implies that celestial bodies obey identical physical laws to those on Earth, and Newtonian mechanics, which first allowed us to understand those laws.

Physical cosmology, as it is now understood, began with the 20th century development of Albert Einstein's general theory of relativity, and better astronomical observations of extremely distant objects. These advances made it possible to speculate about the origin of the Universe, and allowed the establishment of the Big Bang Theory, by Fr. Georges Lemaitre, as the leading cosmological model. Some researchers still advocate a handful of alternative cosmologies; however, cosmologists generally agree that the Big Bang theory best explains observations.


Milky Way Galaxy

The Milky Way is the galaxy that contains our Solar System. Its name "milky" is derived from its appearance as a dim glowing band arching across the night sky in which the naked eye cannot distinguish individual stars. The term "Milky Way" is a translation of the Classical Latin via lactea, from the Greek γαλαξίας κύκλος (pr. galaxías kýklos, "milky circle"). From the Earth, the Milky Way appears like a band because its disk-shaped structure is viewed from within the Galaxy. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. In the past, astronomers thought that all of the stars in the universe were contained inside of the Milky Way. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble definitively showed that the Milky Way is just one of many galaxies.

The Milky Way is a barred spiral galaxy some 100,000–120,000 light-years in diameter which contains approximately 100–400 billion stars. It may contain at least as many planets as well. The Solar System is located within the disk, about 27,000 light-years away from the Galactic Center, on the inner edge of a spiral-shaped concentration of gas and dust called the Orion–Cygnus Arm. The stars in the inner ≈10,000 light-years form a bulge and one or more bars that radiate from the bulge. The very center is marked by an intense radio source named Sagittarius A* which is likely to be a supermassive black hole.


Spiral galaxies

A spiral galaxy is a certain kind of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae and, as such, forms part of the Hubble sequence. Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as the bulge. These are surrounded by a much fainter halo of stars, many of which reside in globular clusters.

Spiral galaxies are named for the spiral structures that extend from the center into the disk. The spiral arms are sites of ongoing star formation and are brighter than the surrounding disk because of the young, hot OB stars that inhabit them.

Galactic astronomy is the study of our own Milky Way galaxy and all its contents. This is in contrast to extragalactic astronomy, which is the study of everything outside our galaxy, including all other galaxies.

Galactic astronomy should not be confused with galaxy formation and evolution, which is the general study of galaxies, their formation, structure, components, dynamics, interactions, and the range of forms they take.


Milky Way

The Milky Way is the galaxy that contains our Solar System. Its name "milky" is derived from its appearance as a dim glowing band arching across the night sky in which the naked eye cannot distinguish individual stars. The term "Milky Way" is a translation of the Classical Latin via lactea, from the Greek γαλαξίας κύκλος (pr. galaxías kýklos, "milky circle"). From the Earth, the Milky Way appears like a band because its disk-shaped structure is viewed from within the Galaxy. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. In the past, astronomers thought that all of the stars in the universe were contained inside of the Milky Way. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble definitively showed that the Milky Way is just one of many galaxies.

The Milky Way is a barred spiral galaxy some 100,000–120,000 light-years in diameter which contains approximately 100–400 billion stars. It may contain at least as many planets as well. The Solar System is located within the disk, about 27,000 light-years away from the Galactic Center, on the inner edge of a spiral-shaped concentration of gas and dust called the Orion–Cygnus Arm. The stars in the inner ≈10,000 light-years form a bulge and one or more bars that radiate from the bulge. The very center is marked by an intense radio source named Sagittarius A* which is likely to be a supermassive black hole.

Galaxy

Locality in astronomy is in theory closeness of the observer relative to the observed astronomical phenomenon under consideration, and thus in practice the relative closeness of the phenomenon to the star system of the Sun.

Being local is an ambiguous condition, and always relative to the order of magnitude of the relevant phenomenon. The term "local" is commonly applied to structures on five successively larger scales beyond the roughly two-light-years diameter of the Solar System:


Magellanic Clouds

The two Magellanic Clouds (or Nubeculae Magellani) are irregular dwarf galaxies visible from the southern hemisphere, which are members of our Local Group and may be orbiting our Milky Way galaxy. Because they both show signs of a bar structure, they are often reclassified as Magellanic spiral galaxies. The two galaxies are:

The Magellanic Clouds have been known since the earliest times to the ancient Middle Eastern peoples. The first preserved mention of the Large Magellanic Cloud is by the Persian astronomer Al Sufi. In 964, in his Book of Fixed Stars, he called it al-Bakr ("the Sheep") "of the southern Arabs"; he noted that the Cloud is not visible from northern Arabia and Baghdad, but can be seen at the strait of Bab el Mandeb (12°15' N), which is the southernmost point of Arabia.

Technology Internet
Human Interest

In journalism, a human interest story is a feature story that discusses a person or people in an emotional way. It presents people and their problems, concerns, or achievements in a way that brings about interest, sympathy or motivation in the reader or viewer.

Human interest stories may be "the story behind the story" about an event, organization, or otherwise faceless historical happening, such as about the life of an individual soldier during wartime, an interview with a survivor of a natural disaster, a random act of kindness or profile of someone known for a career achievement.

Hospitality Recreation
News:


Related Websites:


Terms of service | About
28