Technofender

In the 16th Century, Ferdinand Magellan - a portuguese seaman - was on his journey through the southern hemisphere when he hazed at the sky and saw some strange clouds. Since then, these "clouds" - which in turn are galaxies - were known as the Magellan Clouds.

And ever since until recently, the scientific community was convinced that those galaxies were no more than mere satellite galaxies to ours - the Milky Way.

But, in recent studies conducted by Dr. Gurtina Besla at the Hardvard-Smithsonian Center for Astrophysics, the conclusions tend to point out to another direction.

During the study, the 3D velocities of both the Magellan Clouds - the LMC and SMC - were measured concisely and it turned out that the speed was anomalously high. In fact, two probable explanations were issued to explain the high speed of MCs.

1. The Milky Way as far more dense than ever calculated before, which - by means of gravity effect - would explain the phenomenon.
2. The LMC and SMC are not satellites of the Milky Way, but they are close neighbours approaching our galaxy.

The experimental data proved to the second theory. Once the parabolic orbit was calculated, it showed that the Galaxies are on their first visit to our Galaxy.

The conclusion has led to many puzzling questions. First, our Galaxy has a significant "warp" that extends up to 10000 light years above and beyond the equatorial plane. Until recently, the origin of this "warp" was attributed to the passes of the Magellan Clouds before. As there has not been a "before", further research will - or should - be conducted to explain the phenomenon.

Second, the Magellan Clouds are a mistery by themselves. It’s believed that the Magellan Stream - a stream of hydrogen which covers about 100 degrees from the standpoint of an Earth observer - was formed either due to the tidal interaction between the clouds and the Milky Way or because of the increasingly higher gas pressures when passing next to the Milky Way. No previous pass, then the explanation is unsustainable.

Last but not least, the commonly-accepted mechanism for the formation of the stars in the clouds should be revised. In the history of the star formation of the Magellan Clouds, there has been periods of bursting of stars and then again a new star bloom. In the past, it was attributed to the passes of the clouds close to the Milky Way, but now, it seems factible to think of the interactions between the two galaxies - SMC and LMC - as the main factor to produce these consecutive periods of star breeding and burst.

Though their looks are of a couple of glowing clouds in the sky, to the naked eye, the Large Magellan Cloud (LMC) and Small Magellan Cloud (SMC) are true galaxies. LMC is located at about 160000 light years away from the Earth and is only a tenth of the size of the Milky Way. SMC is located at twice the distance from the Earth, and is only a hundredth of the size of our Galaxy.

Via: Hardvard News