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22 Cards in this Set
- Front
- Back
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Where did most of our knowledge of how the solar system was formed come from?
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Much of our knowledge of how the solar system was formed is gained from direct observations of objects within other galaxies and solar systems – both younger and older.
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What did the planets of the solar system form from?
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The planets of the Solar System formed from a nebula of gas, dust, and ices coalescing into a dusty disk around the evolving Sun.
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Within the disk, what did tiny dust grains and ices coagulate into?
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Within the disk, tiny dust grains and ices coagulated into growing bodies called planetesimals.
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Define a planet.
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A planet is a celestial body that is in orbit around the Sun, has sufficient mass to assume a hydrostatic equilibrium (nearly round) shape, and has “cleared the neighborhood” around its orbit.
This definition does not apply outside the solar system. |
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What do planetary seasons result from?
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Planetary seasons result from two factors: axial tilt and variable distance from the sun (orbital eccentricity.)
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What are factors which affect climate of planets?
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Effects of atmospheres
Composition Density Orbital eccentricity Distance from the Sun Rotational rate Axial tilt Presence of surface liquids Planetary size Albedo Solar wind |
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How were planetary rings created?
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Planetary rings are thought to have been created when small moons collided with others, or ventured too close to their parent planet. The resulting fragments gradually spread out into concentric orbits, breaking into ever smaller fragments through repeated collisions, eventually forming a ring system.
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What is a meteoroid?
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A meteoroid is matter revolving around the sun or any object in interplanetary space that is too small to be called an asteroid or a comet.
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What is the difference between an asteroid and a meteoroid?
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Unofficially the size limit for an asteroid has been set at 50 meters; anything smaller than that is simply called a meteoroid.
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What is the asteroid belt mainly ocmposed of?
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Even though there are a lot of asteroids, the asteroid belt is mostly empty space.
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What is the Oort Cloud?
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The Oort Cloud is an immense spherically-shaped cloud surrounding our Solar System. The vast distance of the Oort Cloud is considered to be the outer edge of the Solar System.
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When does a solar eclipse occur?
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A solar eclipse occurs when the moon passes in a direct line between the Earth and the Sun. The moon's shadow travels over the Earth's surface and blocks out the Sun's light as seen from Earth.
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What occurs during a total solar eclipse?
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During a total solar eclipse the entire central portion of the Sun is blocked out and the Sun's outer atmosphere, the corona, is visible.
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What happens if a penumbra passes over you?
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If the penumbra passes over you, only part of the Sun's surface will be blocked out. You will see a partial solar eclipse, and the sky may dim slightly depending upon how much of the Sun's disc is covered.
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When do you see an annular eclipse and what happens when it occurs?
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In some cases, the moon is far enough away in its orbit that the umbra never reaches the Earth at all. In this case, there is no region of totality, and what you see is an annular solar eclipse.
In an annular eclipse, only a small, ring-like sliver of light of the Sun’s disk is visible. ("annular" means "of a ring"). |
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What are the two types of planetary phases?
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Inferior and Superior
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What happens during an inferior planetary phase?
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The planets, as viewed in the sky, exhibit characteristic aspects and phases. "Aspects" refers to the location of the planet with respect to our overhead sky reference; "phases" refers to the fact that the planets, through a telescope, exhibit phases.
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How are superior planetary phases different from inferior planetary phases?
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The aspects and phases of the superior planets differ from those of the inferior planets because of geometry: their orbits are outside that of the Earth.
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What is Keplers first law of planetary motion?
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The path of the planets about the sun are elliptical in shape, with the center of the sun being located at one focus
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What is Keplers second law of planetary motion?
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The line joining a planet to the Sun sweeps out equal areas in equal times as the planet travels around the ellipse
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What is Keplers third law of planetary motion?
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The square of the total time period (T) of the orbit is proportional to the cube of the average distance of the planet to the Sun (R). (The Law of Harmonies)
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What is Newtons law of universal gravitation?
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F = G ((m(1)*m(2))/(r^2))
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