Venus and Jupiter III
Venus and Jupiter have only a few things in common. They're both planets in our own solar system, for example, and they're both about four and a half billion years old. As seen from Earth, they're both quite bright. And for the next few mornings, they have one more thing in common: they share a small patch of the southeastern sky at first light.
Other than that, Venus and Jupiter have more differences than similarities.
Venus is one of the denizens of the inner solar system -- a region of small, rocky planets. Venus is about the same size as Earth, and it has a similar composition. And it's the hottest planet; a thick atmosphere of carbon dioxide traps heat from the Sun, turning its surface into an inferno.
Jupiter resides in the outer solar system, far from the Sun. It's a giant ball of gas that's about 11 times Earth's diameter. Layers of hydrogen and helium surround its small, rocky core. It's also topped by a thick atmosphere, but until you drop far into it, it's much colder than Venus's. And while Venus has no moons, Jupiter has more than 60 -- along with a few dark rings.
As you look at Venus and Jupiter the next few mornings, though, you'll be hard pressed to tell the difference. They're both brilliant pinpoints quite low in the southeast at dawn. Venus is the brighter of the two. It's a little higher in the sky tomorrow, but Jupiter will move past it the following couple of mornings.
Script by Damond Benningfield, Copyright 2007
For more skywatching tips, astronomy news, and much more, read StarDate magazine.