The Eagle Nebula a cloud in which stars are forming NASA Jeff Hester and Paul

The eagle nebula a cloud in which stars are forming

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The Eagle Nebula, a cloud in which stars are forming NASA, Jeff Hester, and Paul Scowen (Arizona State University) 7 Astronomers have a theory for the origin of our solar system that is consistent both with observations of the solar system and with observations of star formation. The solar nebula theory supposes that: Stars form from cold, dense clouds of gas and dust in interstellar space that collapse under the influence of their own gravity. Planets form in the rotating disks of gas and dust around these forming stars. Our own planetary system formed in such a disk-shaped cloud around the young sun. This Hubble Space Telescope image shows pillars of cold interstellar gas and dust that are part of the "Eagle Nebula,” a nearby star forming region 6,500 light years away. The tallest pillar (left) is about about 4 light-years long from base to tip. Forming inside the pillars are embryonic stars. Eventually, the stars themselves emerge from the pillars as they are eroded away by ultraviolet light from hot, massive, young stars.
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Why do large bodies in our solar system have orderly mo9ons? 8
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As the solar nebula contracted, three things happened to it: Rotation rate increased Flattened into a disk Temperature increased Protosun formed at the center Accreted gas from the disk The beginning of the solar system Artist’s impression of a forming protosun NASA/JPL-Caltech/R. Hurt (SSC) 9 The story of the formation of the solar system starts before the Sun formed. The material that now makes up the Sun was distributed thinly in interstellar space in the form of a large cloud of gas and dust. The Sun began to form a little more than 4.6 billion years ago when this cloud (or part of it) began a process of contraction and flattening. It doesn't take much to start this initial contraction. The cloud only needs to feel a random disturbance (or perturbation) from outside to start the process of gravitational collapse. Most of the collapsing mass collected in the center, forming the Sun, while the rest flattened into a protoplanetary disk out of which the planets, moons, asteroids, and other small Solar System bodies formed.
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Why did the rota9on rate increase? Conservation of angular momentum says that as a rotating object contracts, its rate of rotation must increase. This is why figure skaters speed up when they pull their arms in. Arms out: slow spin Arms in: fast spin Image: Albert Einstein Institute/Markus Pössel Image: Albert Einstein Institute/Markus Pössel 10 While most of the motions in the solar nebula were random, the solar nebula had some small net rotation. For it to have exactly zero net rotation would be highly improbable. So, as the solar nebula collapsed, its rotation rate sped up to conserve angular momentum. This began to turn the random motions of the solar nebula into the orderly motions of the solar system.
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Why did the nebula fl[email protected] into a disk?
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  • Spring '08
  • Solar System, Planet, solar nebula

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