The Milky Way is simply the common name for the galaxy that encompasses our solar system (The solar system is the home to the sun, nine planets including the Earth, the 158 known moons that orbit those planets, as well as a countless number of other celestial bodies that exist throughout this vast space. Such celestial bodies include things like asteroids, meteoroids and comets)The phrase Milky Way came from the band of white light that can be seen across the celestial sphere visible from Earth. This celestial sphere contains a host of various stars and other solar matter. The discovery of the Milky Way is credited to the ancient Greek philosopher Democritus, who was the first person in recorded history to make the assumption that the Milky Way existed and was made up of billions of distant stars.
The Milky Way is pretty, but it's savage, too. It's currently eating several other galaxies. They've been ripped into long, curving arcs of stars that orbit the center of the Milky Way. Eventually they'll merge completely with us, and we'll be a slightly larger galaxy. Ironically though, the galaxies add their mass to ours, making it more likely we'll feed again. Eating only makes galaxies hungrier.
All the stars that the eye can distinguish in the night sky are part of the Milky Way Galaxy, but aside from these relatively nearby stars, the galaxy appears as a hazy band of white light arching around the entire celestial sphere (is an imaginary sphere of arbitrarily large radius, concentric with the Earth and rotating upon the same axis). The light originates from stars and other material that lie within the galactic plane. Dark regions within the band, such as the Great Rift (sometimes called the Dark Rift or, less commonly, Dark Rive, is a series of overlapping, non-luminous, molecular dust clouds that is located between the solar system and the Sagittarius Arm of the Milky Way Galaxy at a distance of about 100 parsecs or about 300 light years "2Ã—1015 miles or 3Ã—1015 kilometers" from Earth. The clouds are estimated to contain about 1 million solar masses of plasma and dust) and the Coalsack (is the most prominent dark nebula in the skies, easily visible to the naked eye as a dark patch silhouetted against the southern Milky Way) , correspond to areas where light from distant stars is blocked by dark nebulae. The Milky Way has a relatively low surface brightness due to the interstellar medium that fills the galactic disk, which prevents us from seeing the bright galactic center. It is thus difficult to see from any urban or suburban location suffering from light pollution (also known as photopollution or luminous pollution, is excessive or obtrusive artificial light).
The center of the galaxy lies in the direction of Sagittarius (is a constellation of the zodiac, the one containing the galactic center. Its name is Latin for the archer, and its symbol is (Unicode â™), a stylized arrow. Sagittarius is commonly represented as a centaur drawing a bow. It lies between Ophiuchus to the west and Capricornus to the east), and it is here that Milky Way looks brightest. From Sagittarius, the Milky Way appears to pass westward through the constellations of Scorpius, Ara, Norma, Triangulum Australe, Circinus, Centaurus, Musca, Crux, Carina, Vela, Puppis, Canis Major, Monoceros, Orion and Gemini, Taurus, Auriga, Perseus, Andromeda, Cassiopeia, Cepheus and Lacerta, Cygnus, Vulpecula, Sagitta, Aquila, Ophiuchus, Scutum, and back to Sagittarius. The fact that the Milky Way divides the night sky into two roughly equal hemispheres indicates that the Solar System lies close to the galactic plane.
The galactic plane is inclined by about 60 degrees to the ecliptic (the plane of the Earth's orbit). Relative to the celestial equator (is a great circle on the imaginary celestial sphere, in the same plane as the Earth's equator. In other words, it is a projection of the terrestrial equator out into space. As a result of the Earth's axial tilt, the celestial equator is inclined by 23.4Â° with respect to the ecliptic plane), it passes as far north as the constellation of Cassiopeia and as far south as the constellation of Crux, indicating the high inclination of Earth's equatorial plane and the plane of the ecliptic relative to the galactic plane. The north galactic pole is situated at right ascension 12h 49m, declination +27.4Â° (B1950) near beta Comae Berenices, and the south galactic pole is near alpha Sculptoris.
The Milky Way is believed to be more than 13 billion years old, which is estimated to be virtually as old as the entire Universe itself. The Milky Way galaxy is actually just one of billions of galaxies contained within the Universe, although very little is currently known about its seemingly infinite galactic counterparts.
The Andromeda Galaxy is a spiral galaxy approximately 2.5 million light-years away in the constellation Andromeda (is a constellation in the northern sky. It is named after Andromeda, the princess in the Greek legend of Perseus who was chained to a rock to be eaten by the sea monster Cetus. It is sometimes called "the Chained Lady" or "the Chained Woman" in English (Mulier Catenata in Latin, al-Mar'at al Musalsalah in Arabic) It has also been called Persea ("Perseus's wife") or Cepheis ("Cepheus's daughter"). The Andromeda Galaxy is named after the constellation, as it appears within its boundaries). It is also known as Messier 31, M31, or NGC 224, and is often referred to as the Great Andromeda Nebula in older texts. Andromeda is the nearest spiral galaxy to the Milky Way, but not the closest galaxy overall. As it is visible from Earth as a faint smudge on a moonless night, it is one of the farthest objects visible to the naked eye, and can be seen even from urban areas with binoculars. It gets its name from the area of the sky in which it appears, the Andromeda constellation, which was named after the mythological princess Andromeda. Andromeda is the largest galaxy of the Local Group (is the group of galaxies that includes Earth's galaxy, the Milky Way. The group comprises more than 30 galaxies (including dwarf galaxies), with its gravitational center located somewhere between the Milky Way and the Andromeda Galaxy), which consists of the Andromeda Galaxy, the Milky Way Galaxy, the Triangulum Galaxy (is a spiral galaxy at approximately 3 million light years (ly) distance in the constellation Triangulum), and about 30 other smaller galaxies. Although the largest, Andromeda may not be the most massive, as recent findings suggest that the Milky Way contains more dark matter and may be the most massive in the grouping. The 2006 observations by the Spitzer Space Telescope revealed that M31 contains one trillion (1012) stars,more than the number of stars in our own galaxy, which is estimated to be c. 200-400 billion.
While the 2006 estimates put the mass of the Milky Way to be ~80% of the mass of Andromeda, which is estimated to be 7.1 Ã— 1011 solar masses, a 2009 study concluded that Andromeda and the Milky Way are about equal in mass.
At an apparent magnitude of 3.4, the Andromeda Galaxy is notable for being one of the brightest Messier objects, making it easily visible to the naked eye even when viewed from areas with moderate light pollution. Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye or when viewed using a binoculars or a small telescope. Speaking of Andromeda, have you ever seen it in the sky? It's visible to the naked eye on a clear, dark, moonless night (check your local listings). It's faint, but big; it's four or more degrees across, eight times the apparent size of the Moon on the sky.
The Andromeda Galaxy and the Milky Way are approaching each other, two cosmic steam engines chugging down the tracks at each other at 200 kilometers per second. Remember galaxies are cannibals that eats each other. Stars don't physically collide; they're way too small on this scale. But gas clouds can, and like I said before, when they do they form stars. So you get a burst of star formation, lighting up the two galaxies. In the meantime, the mutual gravity of the two galaxies draw out long tendrils from the other, making weird, delicate arcs and filaments of stars and gas. It's beautiful, really, but it indicates violence on an epic scale. Eventually it will happen but that's probably a few billion years,they will merge as one bigger galaxy.. what will be the name..? Andromeda way?, Milkromeda..?