The Milky Way Galaxy is but one of the billion galaxies scattered across the Universe. Let's take a deeper look into Earth's home and cosmic neighborhood.
Milky Way Galaxy: Earth's Home
Examining the Milky Way galaxy used to be extremely difficult to pull off. It was the launch of two revolutionary space telescopes that enabled the golden age of research for the Milky Way galaxy.
The roughly 13.6-billion-year old barred spiral galaxy has huge pivoting arms that stretch through the cosmos. The Milky Way's disk has a diameter of roughly 100,000 light-years, while its thickness is equivalent to around 1,000 light-years.
It is because of the galaxy's milky white look while stretching through the sky that the name Milky Way was given to it. In fact, according to Greek mythology, the said milky band first appeared due how Hera sprayed milk in the sky.
Similar to how the Earth rotates the Sun, the solar system orbits the Milky Way's center.
The Earth is situated around halfway to the Milky Way's edge, with a distance of roughly 26,000 light-years from the galaxy's center. The Earth lies inside the Orion Spur, which is an offshoot between Perseus Arms and the larger Sagittarius that lie outwards and inwards of the Earth's location.
At the center of the Milky Way galaxy is the Sagittarius A supermassive black hole. This mostly dormant black hole is quite hard to observe. Nevertheless, it has been seen to have the mass of 4.3 million Suns. The black hole's estimated diameter is 14.6 million miles, or 23.5 million kilometers. It sucks in anything that is situated near to it, which enables it to grow even more gigantic.
While the Milky Way Galaxy is classified as a huge barred spiral galaxy, its bar is quite smaller compared to other similar-sized galaxies. A central bar refers to an oval or circular shaped old star structure that can be found at the core of spiral galaxies.
ALSO READ: 6 Billion Earth-Like Planets Could Be Filling the Milky Way Galaxy, Astronomers Say
Galaxies in the Universe
The Milky Way Galaxy, though unique in and of itself, is just one of the many galaxies that are scattered across the Universe. In fact, based on recent estimates, there could be up to two trillion galaxies across the observable Universe.
This number, however, remains an estimate as no scientist has been able to sit and count the number of actual galaxies out there. Rather than doing so, they examined small areas in the Universe and counted the galaxies present within the said fractions.
The two-trillion estimation is also based on 3D conversion shots taken by the Hubble Space Telescope and also new models for mathematical calculation. Before this estimation, astronomers estimated the presence of around 100 to 200 billion galaxies, but these available supporting methods and models ramped up the estimations.
RELATED ARTICLE: Is Milky Way Special? Astronomer Says Comparison With Other Galaxies Is Necessary To Find the Answer
Check out more news and information on Space in Science Times.
