In an earlier phase of my life, I worked as a professional astronomer, and I've loved space and astronomy since before I could pronounce the words. So naturally, I've gotten a lot of personal pleasure from the free software astronomy tools that are included in my Debian GNU/Linux system. But ironically, I haven't written about them much. Recently, though, I was asked a question which I used KStars to answer, so this is a good chance to talk about how to use it.
KStars is a "planetarium" software for KDE. This means that it is designed to show you what the night sky will look like on a particular night at a particular time in a particular location on the Earth. As you probably know, we are living on a rotating spherical Earth, tilted about 23 degrees from the plane of its orbit around the Sun. And of course, the other seven major planets, five dwarf planets, and zillion minor planets in our solar system are doing much the same.
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