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Pa Pe Pl Pr

Planet Saturn

by | Mar 22, 2020

Saturn is a gas giant made entirely of hydrogen and helium. It sits at the center of a complex system of rings and at least 62 moons. The planet and its companions are almost a complete solar system themselves, as the rings are composed of billions of separate...

Planet Venus

by | Feb 20, 2020

Venus is the second planet from the Sun. In English, Venus is named after the Roman goddess of love and beauty. As the second-brightest natural object in the night sky after the Moon, Venus can cast shadows and, rarely, is visible to...

primary batteries

by | Mar 23, 2020

Primary batteries (single discharge batteries) are used in missions that require one-time use of electrical power for few minutes to several hours. Primary batteries have been used in planetary probes and sample return capsules (Stardust, Genesis, Deep Impact,...