Astrophysicists have finally managed to solve the mystery of the origin of the Magellanic Stream - a puzzle that scientists could unravel forty years. It turned out that this tape is out of gas, which stretches between the Big and Small Magellanic Clouds are the result of the gravity of war between the two galaxies, which are constantly egging ... our Milky Way!
Frankly, the story of the Magellanic Stream has long reminds me of some intriguing detective. Judge for yourself - long known that side of our Milky Way, there are two satellite galaxies, the Large and Small Magellanic Clouds (they are called so because one of these galaxies, which terrestrial observer does seem more strange cloud in the night sky for the first time saw the famous Ferdinand Magellan during his voyage around the world). We also know that from time to time, these galaxies are stealing from each other, as well as in the Milky Way stuff. Thus, they can be easily considered recidivists space with the experience.
However, the most interesting thing is that#39;s what - about half a century ago, scientists discovered a connecting these galaxies long strip of interstellar gas that extends around almost half of the Milky Way. This long gas tape called the Magellanic Stream. However, it is easier to astronomers from this no more - immediately began discussions about where this took the Magellanic Stream. That is quite obvious that this is a banal space traces of the crime - someone stole his neighbors a fair share of the substance. The point, as they say, for small - to understand who steals, from whom and for what purpose. However, in practice this is what was the most difficult.
Originally charged with theft of interstellar gas ... our Milky Way - say, it is this massive galaxy by its gravity pulls together the two clouds of gas. Thus. they say, this tape was formed. After you have decided that the Milky Way did not and - after two satellites closer, it#39;s big cloud start to steal gas from Small. Later, there was also a compromise version - of course, the two clouds from time to time kidnapped substance from each other, but at the Milky Way and did not participate directly in the formation of the gas belt, now our galaxy does affect the orbit of clouds and thus controls the shape Magellanic Stream. In short, all mixed up and permanently confused - well, just like in the good English detective.
However, recently with the Hubble Space Telescope and ground-based Very Large Telescope, astronomers from the Space Telescope Science Institute (USA) and their counterparts from the European Southern Observatory were still able to solve the 40-year-old riddle of the origin of the Magellanic Stream. For this it was necessary to use the data provided by the ultraviolet spectrographs both devices. Scientists interested in presence of six points of the flow of oxygen and sulfur, and their amount. Use the same ultraviolet spectrographs had because both of these elements is quite good at absorbing ultraviolet radiation.
The results showed that in the central part of the flow of oxygen and sulfur is very small. This pattern corresponds well to performance of the Small Magellanic Cloud, about 2 billion years ago. However, in areas close to both the satellite galaxies, the chemical composition of the gas much like the Large Magellanic Cloud. Thus, not only a large cloud of stealing gas from his small brother - Low Cloud also misses an opportunity to steal from her abuser. This suggests that the galaxies are constantly converging between a real gravitational war.
However, do not think that our Milky Way is in the story completely white and fluffy - he also puts his hands in the kidnapping of the interstellar gas. The fact is that all satellite galaxies Milky Way, besides the aforementioned Magellanic Clouds have long lost the bulk of its gas. The clouds also kept it only because they are more massive than the other satellites. However, since these satellites are still continuing their movement - close to the halo of our galaxy, which consists of hot gas, the pressure pushes the interstellar medium gas Magellanic clouds into space. Researchers believe that it is this, together with the very same gravitational war between the Clouds, and spawned the Magellanic Stream.
So, as you see, is not to blame in this story not - all three galaxies can catch in the kidnapping of interstellar gas clouds. But who will ultimately benefit from that? Astrophysicists believe that such will be the strongest, that is our Milky Way - from the time the gas will be captured by its powerful gravity and it would lead to the formation of new stars. Thus confirmed one old rule - when the two fight with each other, benefit from this always gets somebody else ...
