Between 1645 and 1715 almost no sunspots were observed, a solar period which came to be called the Maunder Minimum.

1645年到1715年间，几乎没有任何太阳黑子活动被观察到，这种时期即是所谓的。

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Isotopes of carbon in tree rings and beryllium in ice cores show a drop-off in solar radiation during much of the period.

树木年轮的碳同位素和冰核中钚同位素的检测都显示出在上述阶段的大多数时间内太阳辐射能量出现下降。

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Halley's comet, which reappears about every 75 years, is a 'short-period' comet from a different part of the Solar System called the Kuiper Belt.

哈雷彗星大约每75年会再现一次，哈雷彗星是一个“短期”的彗星，来自太阳系一个名为柯伊伯带的与众不同的部位。

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Curiosity flew to Mars during a period of low to moderate solar activity.

NPR: Astronauts Face Radiation Threat On Long Mars Trip

Italy, meanwhile, last year had announced a program of solar incentives for the 2011-2013 period, with scheduled FIT reductions over time.

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Warren White of the Scripps Institution of Oceanography in La Jolla, California, and his colleagues were the first to find that sea-surface temperatures across the globe swing up and down in a 10-to 12-year period that lags behind the solar cycle by two to three years.

ECONOMIST: The earth��s climate