Galaxies – Home to the Stars
No-one enjoys being alone – even the stars. Every star belongs to a larger system, which we call galaxies. Our Milky Way is the most notable example.
The Milky Way – our home galaxy
Several hundreds of billions of stars, gas and dust along with a black hole at its center – these are the components, which make up the Milky Way. During clear, dark nights we can see the Milky Way with the naked eye. It appears as a shimmering ribbon across the night sky. The diameter of our galaxy is an unimaginable 100,000 light years. In comparison to our solar system with a diameter of one light day, the Milky Way dwarfs our celestial neighborhood.
At the beginning of the last century, we did not know that there were other galaxies in the Universe. An exact number of galaxies is likely to remain a mystery to us, however. Our nearest neighbor, Andromeda (sometimes referred to as the Andromeda Nebula) is visible from our vantage point on Earth and without optics. Some may wonder about the term Nebula here, since Andromeda is indeed a galaxy. An explanation for using nebula is simple: the term nebula loosely refers to all objects, which appear blurry – even with a telescope. Since observers of a hundred years ago did not know that our Universe is made of more galaxies than our own, they also did not know that the Andromeda was actually an entirely separate galaxy! The designation of nebula was as a result obvious. Even today, galaxies are sometimes referred to as extragalactic nebula, despite them being entire star systems.
For anyone, expecting to witness a broad spectrum of magnificent colors and innumberable stars, should not be disappointed when gazing up at the night sky and seeing Andromeda as only a bright spot in a sea of darkness. Using a telescope or even Deep-Sky Mode in Universe2go can satiate your appetite for objects otherworldly. With both, you can discover a welath of other galaxies!
Gazing into the night sky is well worth it, because, much like snowflakes, no two galaxies are the same. There are elliptical galaxies, in which the stars are almost perfectly spread out, and irregular galaxies, in which the stars appear to have no discernable structure. Many other galaxy types include spiral galaxies or wagon wheel galaxies, in which the stars are concentrated in the center. In any case, your voyage has just begun and has plenty to offer.
Image Source: Martin Hartmann & Stefan Krause