Astronomy — The Milky Way Galaxy, our home galaxy
The Milky Way Galaxy, home to our solar system
- The Milky Way Galaxy contains roughly 150 billion stars, and is roughly 100,000 light-years in diameter. The galaxy is about 15,000 light-years thick in the middle.
- There is a ‘nuclear bulge’ in the center of the galaxy and it is thinner on the outer edge.
- The hub of our galaxy lies in the direction of the constellation Sagittarius.
- The Sun completes one rotation around our galactic center in about 250 million years.
- The average distance between stars in our galaxy is 36 trillion miles (6 light-years).
- Our galaxy has two smaller satellite galaxies, called the Magellan clouds. The Andromeda Galaxy also has satellite galaxies.
- Our galaxy formed over 10 billion years ago.
- Every celestial object visible to the naked eye is part of our galaxy, with only 2 exceptions: 1) The Magellan clouds 2) Andromeda Galaxy.
- Galaxies, like stars, are dominated by their own gravity.
- Our galaxy rotates. Each of the billions of stars exerts a gravitational attraction on all the others, thus pulling all stars toward the center. To keep the galaxy from collapsing inward, each star must move in its own orbit around the center.
- The mass of our galaxy is about 100 billion solar masses (lower limit)
- Stars at the center of our galaxy are only 1000 A.U. apart. Stars near our Sun are about 330,000 A.U. apart.
- Active galaxies emit up to 10 million times more radio, UV, or X-ray energy than non-active galaxies.
- Double-lobed radio galaxies are formed by a double exhaust system.
- It is probable that black holes lie at the center of galaxies with active cores.
- Our galaxy is moving at 360 miles per second in the direction of the constellation Leo.
- Radio astronomers have found strong evidence that at least 2 planets circle a fast-spinning pulsar in Virgo. The inner planet takes 66.6 days to orbit at a distance of 36 million miles, while the outer one completes a circuit every 98.2 days at 48 million miles. The two worlds have masses of at least 3.4 and 2.8 Earths, respectively. A wind of energetic particles and radiation strips the planets of any atmosphere, leaving their surfaces parched and inhospitable.
- One Japanese astronomer claims the Milky Way Galaxy is cigar-shaped. His finding was based on the distribution of gas density in the central part of the galaxy.
- Inside our wheel-shaped galaxy there are between 100 and 200 billion stars. Many of these stars stand in the line of sight of a closer star, and many more are hidden behind veils of dust. Even if we could see them all, it would take 4,500 years to count them at a rate of one per second, counting 24 hours per day, 365 days per year. If you were Noah and had lived from the flood until the present, and used all your time counting, you would just now be completing the task.
- The speed of galactic rotation — Our Sun, carrying the Earth, Moon, and all the solar system with it, is hurtling through space at a terrific rate of speed. The Sun’s orbital speed around the hub of the galaxy is 135 miles per second or 540,000 miles per hour. The solar system is continuously pulled toward the center of the galaxy by gravity, and continually pulled away from the center by centrifugal force. These forces equalize themselves, thus locking the sin into an elliptical orbit around the galaxy’s core. There is no evidence that the Sun’s movement has ever increased its speed or slackened its pace. This motion is in addition to the 65,500 miles per our that our Earth circles the Sun.
- Dynamic galactic rotation — The billions of stars (suns) in the Milky Way galaxy are each independent from each other (except for binary stars). Each star has a separate orbit and speed around the center of the galaxy. Stars at a distance of 5000 light-years from the center travel at a velocity of 350,000 miles per hour. At this speed, it takes stars 56 million years to complete one orbit around the galactic center. There is a different tangential velocity for each distance from the core of the galaxy. The speed increases to 500,000 miles per hour at a distance of 25,000 light-years from the galactic core, and then begins to slow down toward the outer edge of the galaxy.
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