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really big test :O


The _________ likely way to cause a nebula to collapse is by the introduction of energy and particles from the explosion of a nearby star or colliding with another nebula.

smaller objects

In a new solar system planets grow in size by the impact of ________________.

nuclear fusion

The core of the sun is powered by ______________,


The earth rotates ________ a day on its axis.


In space the smaller an object the more likely it is to have an ____________ shape.


The energy of the sun is produced in the __________.


A ________ is a large cloud of dust and gas that moves around in space.


The _____________ zone of the sun is so dense that it takes a long time for energy to pass through it.


It is believed that much of the water present on early _________ was formed from condensed volcanic gases.

large, short

A planet with a __________ orbit has a long period of revolution and a planet with a ________ orbit has a short period of revolution.


Kepler's __________ law states that the planets move around the sun in an elliptical orbit.


Kepler's _______ law says that planets move faster as they get closer to the sun.


Kepler's ________ law says that if we know the period of revolution of a planet, the planet's distance from the sun can be calculated.


The ____________ separated into layers because its interior was a liquid and all the dense materials like nickle an iron sank to the center while the lighter material floated to the surface.

Celestial Bodies

______________ like stars and planets are shaped like spheres because the gravity is so great that it causes the material to be pulled towards the center from all sides.


A solar system begins as a _________ which is pulled together by gravity to form a solar nebula where bits of dust and rock from planetesimals that even eventually develop into planets which are made of rock and gas.


______________ keeps a nebula from collapsing in on itself.


A _______ will eventually collapse and become a rotating solar nebula


Mercury, Venus, Earth and Mars are ___________ planets.


Jupiter, Saturn, Uranus, Neptune are considered to __________ giants.


____________ is a force that all matter has. It is increases when objects move closer to each other.


____________ pulls dust and gases together to form nebulas.


Small objects such as asteroids and meteoroids are more likely to have ___________ shape.


Impacts of ___________ into each other brought new material to the planets, dug craters and released energy.

nuclear fusion

____________ is the process by which two molecules fused together to make a new element. This process releases more energy than any other process known to man.


The closer a planet is to the sun the _________ its period of revolution is.


The ____________ is the outermost layer and has the lowest density of all of the earths layers.


The majority of all the __________ on earth came from other planets.


Earth's ________ atmosphere was made primarily of carbon dioxide.


_____________ are dark cool areas on the Sun's surface caused by storms.

solar system

As the ______________ formed solar winds caused by the sun blew the lighter gas materials to the outer part of the solar system. Thus, the remaining dust created the rocky inner planets while the outer planets form from gas.


_________ are icy planetesimals that come from outer parts of the solar system on their journey around the sun.


The ____________ is the outer most atmospheric layer of the sun.


The __________ is the layer of the sun's atmosphere that touches the surface.


The __________ is the visible surface of the sun.


The __________________ is the layer of the sun where gases circulate to the surface.

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