Second Life is not a dedicated virtual globe or virtual planetarium but a free-form three-dimensional programmable space that anyone can use to build globes and planetariums in. One impressive recent example is the virtual planetariums built by Magnus Zeisig, one of Sweden’s most talented SL programmers.
If you visit his space in Second Life, you get to walk around and through a number of exhibitions, including an programmable orrery, walk-through 3D maps of nearby stars and galaxy clusters, and a 3D browsable database of planets, satellite and asteroids — even those with weird shapes like Phobos and Deimos.
Navigating through these exhibits in 3D with an avatar gives a real sense of depth and distance — its an original and unusual perspective on these datasets.
Magnus writes that he will be collaborating with the International Astronomical Union for the International Year of Astronomy in 2009, and he’s also been commissioned to build a larger version of his work for an American university. You can read more about what Magnus has been up to in a PDF newsletter (in English) where he explains his project in his own words. This being Second Life, you can of course buy your own copies of Magnus’s planetariums, and set them up in your virtual Second Life pad.