Fourth planet from the sun. Mars is about 141 million miles (about 228 million kilometers) from the sun and revolves around the sun in 687 days. Mars is smaller than Earth, about 4,221 miles (about 6,796 kilometers) in diameter. A Martian day is only about 40 minutes longer than our…

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Earth Day eBook SaleWednesday April 11, 2018

Earth Day eBook Sale

I am so pleased that HarperCollins is doing a special promotion with two of my books for Earth Day. Between now and April 23, the eBook editions of two of my books, GLOBAL WARMING and WILDFIRES, will be on sale for just 99¢…

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