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21 Cards in this Set
- Front
- Back
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The Sun is a ________ star.
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Yellow. Our Sun is a Yellow Dwarf star and the center of our solar system.
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Life on Earth depends on _________________ from the Sun.
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Energy. Energy, in the form of light and heat, make life as we know it possible.
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Earth's orbit is about about _____ million miles in diameter.
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93. This is equivalent to one Astronomical Unit (AU). Despite this terrific distance, it takes only 8 minutes, 18 seconds for light from the Sun to reach Earth.
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The Sun's internal temperature is estimated at ______ degrees Kelvin.
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13,600,000. By contrast, the surface of the Sun is about 5,600 degrees Kelvin (10,000 Fahrenheit).
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The Sun's energy comes from a process of ______________.
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Nuclear fusion. In this process, two Hydrogen atoms are combined to form Helium. As the reaction completes its cycle, energy is released into space.
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The Sun's energy is created in its _____________.
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Core. The nuclear fusion that "powers" the Sun occurs deep within its interior or core.
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The Sun's _____ is so dense that it is considered solid.
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Core. The Sun's "nuclear power plant" is made of dense gases.
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The inner layer of the Sun's atmosphere is its ________.
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Photosphere. This region is typified by intense magnetic activity, inhibiting convection and reducing surface temperature.
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Dark, cooler regions of the Sun's surface are visible as _______.
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Sun Spots. These are typically 1,000 or more degrees cooler than the other areas of the photosphere.
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Sun spots ______ permanent features of the Sun.
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Are not. The presence or absence of Sun Spots seems to depend on the Sun's place in its 11-year cycle.
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The middle layer of Sun's atmosphere is called the ___________.
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Chromosphere. This layer exists just above the photosphere.
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Plasma explosions from the chromosphere are called __________.
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Solar Flares. Flares seem to occur within the vicinity of Sun Spots. Like Sun Spots, Solar Flares seem to occur on a cyclical basis.
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The ______ is the outermost layer of the Sun.
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Corona. This is largest layer of the Sun's atmosphere and what we see during a total solar eclipse.
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_________ are the constant stream of ionized gas particles flying from the Sun into the solar system.
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Solar Winds. These streams of protons and neutrons flow from the corona into space.
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The ______ represent the point at which the sun crosses the plane of the Earth's equator.
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Equinoxes. These twice-yearly events create days and nights of approximately equal length.
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A ________________ occurs when the moon blocks sunlight to Earth.
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Solar eclipse. This is a solar eclipse.
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A planet's __________ is the point in its orbit when it is closest to the Sun.
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Perihelion.
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A planet's __________ is the point in its orbit when it is farthest from the Sun.
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Aphelion.
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The point in the year when the Sun reaches its highest point is the ___________.
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Solstice. The winter solstice, around December 21, marks the Sun's lowest point and the summer solstice, around June 21, marks its highest point.
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________ is the time of day when the Sun is highest in the sky.
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Solar noon. Because of the synchronization of time zones, solar noon and clock noon rarely coincide.
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High energy solar particles captured in Earth's magnetic field are believed to cause ________.
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Aurora. These lights in the sky tend to occur at the polar lattitudes, and so are commonly called the Northern (or Southern) Lights.
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