|Released: January 25, 2009|
Retired: January 26, 2009
Our solar system is part of a larger celestial system called a galaxy. Galaxies are comprised of stars, gas and dust which are kept together by gravity. Researchers have estimated that the number of galaxies in the visible universe is greater than 100 billion yet only a fraction of them have been photographed through telescopes by astronomers. On today's quest we will explore what is known about galaxies, including our own galaxy, the Milky Way.
|1000 Credits||Released: May 22, 2008|
|Galactic Star Chart||Quest Prize||VFK Galaxy Quest||Released: January 25, 2009|
Retired: January 26, 2009
1. The name of our galaxy, "the Milky Way" is translated from the Latin name "Via Lactea". This is derived from "Kiklios Galaxios" which is Greek for milky circle. If you look up at the night sky away from city lights, you can see what resembles a path of light sweeping across the sky. Who is the Greek scientist and philosopher who first proposed that the Milky Way was actually the light of distant stars?
2. In 1785, William Herschel, one of the most famous astronomers of the 18th century, created a map of the Milky Way. He pioneered the study and measurement of the stars as they were distributed in space. In addition to discovering the planet Uranus, clusters of stars, binary stars and many new nebulae, Herschel was the first to describe the correct form of the Milky Way. He counted the stars that he could see and decided that they made an enormous disk shaped formation. Go to Ned Kelly's shack in Australia and say this quote by Democritus, "By desiring little, a poor man makes himself rich."
3. When dealing with objects in space and distances in the universe, the unit of measurement is a light year. A light year is "the distance that light travels in a vacuum in a year." This distance is approximately 5.88 trillion miles. The millions of galaxies which have been photographed by astronomers have been within 13 billion light years of Earth. How many galaxies which are outside of our own galaxy, the Milky Way, can be seen from Earth without a telescope?
4. There are only three galaxies which you can see from the Earth without the magnification of a telescope. If you are in the Northern Hemisphere, you can see the Andromeda Galaxy. This galaxy is approximately 2 million light-years away from Earth. From the Southern Hemisphere you can see the galaxy called the Large Magellanic Cloud, which is approximately 160,000 light-years away. The third galaxy, the Small Magellanic Cloud is approximately 180,000 light years from Earth. Go to the crossroads outside the gate of the garden of your colonial room and say this quote from Wernher von Braun an astronautics engineer and one of the leading figures in rocket development. Say "Man is the best computer we can put aboard a spacecraft."
5. There is no consistent distribution to galaxies in space. There are some which are alone in their area of space, while other galaxies are found in twos where they are orbiting each other. The majority of the galaxies occur in groups. The groups can be comprised of only a few galaxies to many thousands of galaxies, and can have a diameter up to ten million light-years. What are these groups of galaxies called?
- Galactic Collections
6. The galactic clusters are further grouped into bigger systems of galaxies referred to as superclusters. These superclusters are grouped into even larger groups which are connected into filaments and strings surrounded by empty space called voids. These networks can be huge. One such enormous network of galaxies is over 500 million light-years long by 200 light-years wide. Go to the castle gate in Medieval Age and say the name of this huge galactic system: "It is called the Great Wall."
7. Galaxies are categorized by their shape. There are three basic shapes for galaxies: spiral, elliptical and irregular. Spiral galaxies look like huge pinwheels with large arms which coil out from the bulging center, and rotate slowly around their center. The Milky Way is a spiral galaxy. New stars appear to be forming from dust and gas within a spiral galaxy. How long does it take for the Milky Way galaxy to make a complete revolution?
- About 25,000 years
- About 250,000 years
- About 25 million years
- About 250 million years
8. Elliptical galaxies can vary in shape from nearly round to flattened spheres. This type of galaxy is brightest at its center growing gradually fainter towards its outer regions. It appears that elliptical galaxies rotate much slower than spiral galaxies. Some also appear to not rotate at all. Within the galaxies, the orbits of the stars look random. This type of galaxy has far less gas and dust than spiral galaxies, and new stars do not look like they are being created. Irregular galaxies predominantly lack a shape and may appear as a cloud of gas with stars. They are often misshapen due to the gravitational influence of another galaxy close by. Go to the dark forest room in Audubon's Wildlife Adventure game, and say: "A long time ago in a galaxy far, far away."
9. The dust, gas and stars of a galaxy are organized into several parts: the bulge, a disk which contains the spiral arms and a halo (Elliptical galaxies have the halo and central bulge, but lack the disk). The bulge part is a spherical shape. In the Milky Way, the bulge is approximately 10,000 light-years across and is comprised of old stars along with gas and dust. The disk part is the huge flattened pancake shaped formation which in the case of the Milky Way is approximately 100,000 light years across and 1,000 light years thick. It is comprised primarily of younger stars, gas and dust which are concentrated into "arms." The spiral arms begin at the center of the galaxy and extend outward in curved extensions. The halo contains "globular clusters" of old stars and matter which cannot be seen, but whose gravitational force can be measured. What is this unseen matter called?
- The Force
- The Abyss
- The Void
- Dark Matter
10. Some of the primary components of galaxies are stars. Stars are categorized by their color, which gives information about their age. Blue stars have shorter lifetimes than red stars, and are very hot. Areas of galaxies that are currently forming stars are bluer than areas where stars are not being formed. Go to Merlin's square and say the last part of Galileo's quote: "The Milky Way is nothing else but..." say: "a mass of stars planted together"
2. Go to Ned Kelly's Shack and say, "By desiring little, a poor man makes himself rich."
4. Go to the Crossroads and say, "Man is the best computer we can put aboard a spacecraft."
6. Go to the Castle Gate and say, "It is called the Great Wall."
7. About 250 million years
8. Go to the Dark Forest and say, "A long time ago in a galaxy far, far away."
9. Dark Matter
10. Go to Merlin's Magic Shop Square and say, "a mass of stars planted together".