China Luna Rover

Top Photo: Chang’e-4 spacecraft on the far side of the moon

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As of press time, many places like the Smithsonian Museum of Natural History were closed.

Top Photo: As of press time, many places like the Smithsonian Museum of Natural History were closed.  Photo credit: Wikimedia Commons photo

Politics Shut Down Federal Government... Read more

The use of objects for exchange goes back to ancient times. Sometimes people would barter things directly, but they also used currency to trade goods. Natural items like shells were used as money to make trading easier.The shekel in Mesopotamia—the oldest known CURRENCY—was used about 5,000 years ago. By the first millennium (1–1000 A.D.) coins made of materials like lead, copper, silver and gold were being used in Europe, Asia and Africa.

Paper money, like coins, could be easily carried and made trading faster and more convenient. But paper money has its problems, including...Read more

The bull shark is one of the fiercest predators in the ocean.

Top Photo: The bull shark is one of the fiercest predators in the ocean. Photo credit: Martin Prochazkacz/shutterstock.com

SHARK! It is a bone-chilling cry that sends swimmers and surfers alike... Read more

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