The Planet Quiz Show  

Answer for Students:

The solar system formed when a large cloud of gas and dust was pulled together by gravity. Most of the gas and dust went into forming the sun in the center of the cloud. Leftover gas and dust formed the planets, their moons, and all of the other objects in our solar system that circle the sun.

Answer for Teachers:

The theory that details the formation of our solar system is called the Nebular Hypothesis. The sun and planets were the natural result of a small portion of a huge interstellar cloud of gas and dust that contracted under the force of gravity. This happened about five billion years ago. As the cloud collapsed, its rate of rotation increased. The cloud flattened and grew smaller as gravitational forces pulled most of the material towards its center. A considerable amount of matter was left behind circling the early protosun. The nebula heated as it collapsed, producing strong magnetic fields near the cloud’s center. The magnetic fields modified the chemical composition of the nebula by selectively pushing volatile (low melt) elements and compounds away from the sun while allowing the higher melt, more refractory, elements to condense near the sun as the nebula cooled. This set the stage for the formation of the small, dense inner planets and the huge, low density outer planets. As the nebula began to cool, gases condensed and coalesced first into very small bodies called grains. Gentle collisions of grains built up larger bodies called planetesimals that continued colliding to form protoplanets. The protoplanets, which were massive enough to have substantial gravitational fields, were quickly assembled into the planets, moons, and other objects found in the solar system today. Once the sun began thermonuclear fusion in its core, the initial energy released blew away the remaining gases and dust, clearing the nebular cocoon in which the solar system had formed.

Eagle Nebula--Pillars of Creatio--(M16): This is the famous Hubble Space Telescope photograph showing the Pillars of Creation. It is where stars are being born. The picture is considered to be one of the most beautiful astronomical photographs ever imaged. The black and white version of this picture (insert), taken with a small telescope, shows many of the major details shown in the Hubble image. These include the three pillars, their luminous tops, and the bridge of material which is emanating from the smallest pillar. The pillars themselves are dust clouds immersed in a glowing cloud of hydrogen gas. They are stellar nurseries. Imbedded within their tips are contracting clouds of hydrogen on their way to becoming stars. Radiation being released by new stars above and outside of the field of the picture, are shredding the tips of the pillars, revealing where stellar birth is occurring and causing the dust to be blown away creating the pillars. Eventually, the dust within each of the globules will be pushed away as the new stars emerge from their cocoons. Astronomers are uncertain whether the protostars will become stars or be shreaded along with the rest of the pillars. The Pillars of Creation is a more recent name given to the Eagle Nebula which is about 7000 light years away from us in the constellation of Serpents, the Snake. The black and white photo was taken by John Sefick at Chaco Observatory in Chaco Culture National Historical Park in northwestern New Mexico.


Deep within the Orion Nebula which can be found in the sword of Orion, the Hunter, is another stellar nursery. Look in the small rectangular box, and then follow it up to the bigger box. There you’ll see some dark blobs. These are called Proplyds, and are clouds of contracting gas and dust. Within these clouds stars are being born. When the new stars begin to change hydrogen into helium deep within their cores, the energy being released will push away the remaining gas and dust to reveal the new star. Hubble Space Telescope photos...

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