They’re doing some very innovative work in solar energy.“innovative” here means something out of date.
A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?()
A flight to other solar systems will be made more possible by ______.
How much of the solar radiation can be converted into usable energy?
A sidereal day is shorter than a solar day. This difference is due to().
In astrology, the earth is regarded as the center of the solar system.
____
In astrology, the earth is regarded as the center of the solar system.
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A sidereal day is approximately how much shorter than a solar day?()