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The most conspicuous features on he surface of the sun are dark blemishes called


THe layer of the sun which radiates most of the light that reaches the earth is called the


The sun's energy results from the conversion of hydrogen into


The layer of the sun directly above the photosphere is called the


The sun is considered an "average star"


The period of the moon's rotation is equal to its period of revolution


The length of daylight on the moon is about

two weeks

The source of the sun's energy is

nuclear fusion

When viewed from earth the dark-appearing ares on the moon are called


Which lunar features is the oldest

lunar highlands

An eclipse of the moon (lunar eclipse) can be seen by anyone on the night side of the earth


Most of the moon's craters were produced by

the impact of debris

Streams of atomic nuclei, protons, and electrons and emitted from the sun produces

the solar wind

During periods of high solar activity high cloud like structures that appear as great arches extending from the sun are often produced. These solar features are called


Radio telescopes are able to detect very short wave radiation emitted by celestial objects


To determine whether a celestial body is approaching or receding from the earth astronomers employ


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