Magellanic Clouds Facts

Magellanic Clouds Facts
The Magellanic Clouds are two irregular galaxies that orbit the Milky Way galaxy once every 1,500 million years and each other once every 900 million years. Both galaxies are visible from the southern hemisphere. The galaxies are the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC). Until the discovery of the Sagittarius Dwarf Elliptical Galaxy in 1994, they were the closest known galaxies to our own. The LMC lies around 160,000 light years away and the SMC is about 200,000 light years away, with an estimated distance of 75,000 light years between them.
Interesting Magellanic Clouds Facts:
The Magellanic Clouds are both rich in gas, meaning they have a higher portion of their mass as gas and they also have less portion of their mass bound up in metallic elements.
The Milky Way is consuming gas that is flowing from the galaxies and eventually these two smaller galaxies might collide with Milky Way.
The LMC lies about 163 thousand light years from Earth and the SMC is about 200,000 light years away.
The LMC is about twice the size in diameter of the SMC. The LMC is 14,000 light years and the SMC is 7,000 light years. To compare, the Milky Way is about 100,000 light years across.
The Magellanic Clouds differs from our galaxy in two major ways. They have a higher fraction of their mass is hydrogen and helium compared to the Milky Way and they are more metal-poor than the Milky Way. Also, they have a different structure and lower mass.
The galaxies were used as predictors of winds to the Māori who were indigenous Polynesian people of New Zealand. They also served as important navigation markers to the early Polynesians.
For many years, astronomers believed that the Magellanic Clouds have orbited the Milky Way at approximately their current distances, but evidence suggests that it is rare for them to come as close to the Milky Way as they are now.
Astronomers now believe the Magellanic Clouds have both been greatly distorted by tidal interaction with the Milky Way as they travel to it. Their gravity has affected the Milky Way distorting the outer parts of the galactic disk.
Recent studies of the SMC completed by astrophysicists D.S. Mathewson, V.L. Ford and N. Visvanathan indicate that it might be a former single galaxy that has split into two remnants. They suggest there is a smaller section of this galaxy behind the main part of the SMC and separated by around 30,000 light years. The reason for this is due to a past interaction with the LMC splitting the SMC and that the two sections are still moving apart. They call this smaller remnant the Mini Magellanic Cloud.
The LMC contains a highly active starbirth region called the Tarantula Nebula. It is a part of a larger cloud of gas and dust. Its high rate of star formation may be caused by compression of interstellar gas and dust by the collision of the cloud with the interstellar medium. The LMC was also a host to a supernova (SN1987A) and was the brightest observed in over four centuries.
They are members of the Local Group which is a galaxy group that includes the Milky Way. It comprises more than 54 galaxies, most of them dwarf galaxies.
The Magellanic Clouds are often reclassified as Magellanic spiral galaxies because they both show signs of a bar structure.

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