Viewing the Night Sky with Linux, Part II: Visit the Planets With XEphem - page 2

Quirky and Powerful

When you run your newly installed XEphem, initially you'll see the control window. Set your location (be sure to click Set before you close the dialog), and set Local Time if you're trying to answer a specific question like "What was that bright object last night?" Then click Update.

To see the sky, go to View->Sky View. You can zoom in with the scrollbar on the left; the right and bottom scrollbars let you move around the sky. The History menu gives you a fast way to some useful views. For instance, try History->West horizon.

You can see that at sunset Venus, Mercury and Mars are all visible. Right-click on any of them to get more information like what times they rise and set. If you want to find any other planets, the Favorites menu will take you there.

Along the top of the window are buttons controlling what you can see. You can easily show or hide constellation names and figures, star names, solar system objects, and various other classes of objects. The buttons down the left and right sides control more esoteric values that you probably won't need to change.

XEphem doesn't show the horizon by default. You can turn it on with a button in the top toolbar. But there's a problem: the default horizon seems to put you in a canyon surrounded by huge mountains! To get a flat horizon, bring up the Control->Horizon... dialog and click on Constant. You can also customize your horizon: click on Edit with Mouse to draw it interactively.