The Milky Way galaxy is a barred spiral galaxy, one of the hundreds of billions of galaxies in the observable universe. It’s also our home.
Like other galaxies, the Milky Way is an isolated collection of stars and other matter combined by common gravity. In addition to the 100-400 billion stars in our galaxy, Equal number of planets It may be in the Milky Way — some of them are part of the solar system and some are free to float. Between the stars are a myriad of nebulae, which are clouds of gas and dust.Most of the interstellar gas hydrogen And helium..
However, there is multiple evidence. Most importantly, the material in the galaxy orbits the center too fast for the galaxy to hold together. gravity Visible Objects — Most of the Milky Way’s mass suggests that it is composed of some form of matter that does not interact with light.Astronomers call this Dark matter, And its true nature is not fully understood.
Who discovered the Milky Way?
Seen from our vantage point on Earth, the Milky Way looks like a band of diffuse light that arcs across the night sky. This is the origin of the English name. The Romans called it via Lactea And I imagined it as a spilled milk band. Astronomers and philosophers discussed the nature of the Milky Way until Galileo Galilei first observed it with a telescope and discovered that the Milky Way’s light came from a myriad of distant stars. The stars themselves are too far to see everything individually, but their combined light gives them a familiar band.
Until the early 1900s, astronomers assumed that the Milky Way contained all the stars in the universe (the Milky Way stretched to fill the entire universe, or was surrounded by infinite space of finite size. T).But in the early 1920s, astronomers Edwin Hubble A closer look at the Andromeda Galaxy reveals that it is an “island” of stars, itself a galaxy, millions of light-years away from us. According to Britannica..
What does the Milky Way look like?
The Milky Way is a relatively thin, flat disk. This explains why it appears as a band in our sky. As we look in the direction of the disk, Earthlings see the combined light of all the stars in the galaxy. Looking away from the disc, you can only see nearby stars. Solar system..
The Milky Way has three main parts: core, disc, and halo.
The core is not spherical. It is stretched in the shape of a rod everywhere with a length of 5,000 to 20,000 light-years. Up to a quarter of all the stars in the Milky Way are in the core. According to it, the density of stars there is up to one million times higher than that near the Sun. Space Telescope Science InstituteThere is Sagittarius A * in the center of the galaxy. This is a supermassive black hole with a mass 4.1 million times that of the Sun. University of California, Los Angeles Galactic Center Group..
The Milky Way galaxy’s stellar disk has a radius of 75,000 to 100,000 light-years, but is only about 1,000 light-years thick. Within the disc are several major swirl arms. According to NASAThese arms stand out visually when star and gas densities are higher than average and star formation occurs at a higher rate.
Our solar system is in a disk near the inner edge of the Orion Arm, about 27,000 light-years from the Galactic Center.
Beyond the Milky Way disk is a halo, a spherical area with a radius of about 100,000 light-years. The halo contains old stars and globular clusters, all orbiting the galactic center in random directions. According to a study published in the journal in 2019, dark matter extends further from the center to up to 400,000 light-years. Astronomy and astrophysics..
Where is the Milky Way?
The Milky Way has two major satellite galaxies, the Large and Small Magellanic Clouds, and dozens of smaller satellites. Our closest neighbor is the Andromeda Galaxy, about 2.5 million light-years away. The Milky Way, along with the Andromeda Galaxy and about 80 small galaxies, is part of a local group. The local group is a group of galaxies about 10 million light-years in diameter, connected by a common gravity. According to Swinburne University..
The local group is a member of one of the larger structures called Virgo Supercluster, surrounded by several large intergalactic voids. According to Durham UniversityAt the center of this Supercluster is the Virgo Cluster. The Virgo Cluster is a large collection of 1,000 to 2,000 galaxies about 54 million light-years away. The Virgo Supercluster itself is considered to be a component of an even larger structure called the Laniakea Supercluster.
How big is the Milky Way?
It is difficult to estimate the true size of our galaxy because we live in the galaxy and all clouds of gas and dust obscure our observations. Astronomers estimate that the total mass of the Milky Way is about 1 trillion times the mass of the Sun. According to NASAMost of its mass is in the form of much dark matter. Stars make up only about 1% of the galaxy’s mass, and interstellar gas makes up only 0.1%.
Is the Milky Way moving?
Scientists reported on a preprint server that the Milky Way is moving at about 391 miles per second (630 kilometers per second) compared to the general expansion of space that separates galaxies from each other (on average). arXiv Our galaxy is in the process of colliding with the Andromeda galaxy, and our two galaxies will collide and begin to merge about 5 billion years later.
Both the Milky Way and Andromeda are moving together in the direction of the so-called Great Attractor. Institute for Astronomy, University of Hawaii report. The Great Attractor is considered to be the center of the Laniakea Supercluster. However, it is difficult to observe the universe in this area because it is past the direction of the galactic center and the view is obstructed.
— —California Academy of Sciences There is this amazing educational video that allows students to tour the Milky Way.
— This National Geographic Book “Visual galaxy“I have a gorgeous image of the Milky Way.
— Check out these activities and resources for our solar system and night sky. University of Texas McDonald..
What is the Milky Way?
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