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More Moon and Planets
Like dogs and Heinz condiments, there’s a wide variety of planets. That’s true even here in our own solar system, where three planets are in view this evening.
Venus is the brilliant “evening star” quite low in the western sky shortly after sunset. Saturn is close to the lower right of the Moon, with orange Mars farther to the left of the Moon.
Venus is our closest planetary neighbor. And it’s also the planet that’s closest to our own Earth in size and mass. Its surface, though, is quite different from Earth’s. The temperature is hot enough to melt lead, and the pressure is the equivalent of being about two-thirds of a mile deep in Earth’s oceans. And the atmosphere is topped with an unbroken blanket of clouds that are made of sulfuric acid.
Mars is only about half of Earth’s diameter. Its air is thin, cold, and dry, although a few clouds scud across the sky. Its surface more closely resembles Earth’s than that of any other known planet, with riverbeds, ice caps, sand dunes, and other familiar features.
Saturn is a planetary giant. It’s about nine times Earth’s diameter, and it’s encircled by beautiful rings and an entourage of dozens of moons. The planet has no solid surface, though — it’s a big ball of gas. And its upper atmosphere is cold and turbulent, with storm systems as big as Earth swirling through its clouds — part of the great variety in the solar system’s planets.
We’ll have more about the Moon and Mars tomorrow.