First light (software edition)

I’m dorking around with plotting all the stars in the Hyg database in Javascript / HTML using D3. Here’s the “first light” for my code, where I generated a GeoJSON file with the 100 brightest stars and loaded it up in QGIS in a simple projection.

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Yeah, it’s not much, but you can see Polaris way up on the north and Orion there in the left middle. It’s flipped left/right because of the naive translation of coordinates (alternately because we’re looking at the sphere inside out).

I haven’t found a good flat map of the entire celestial sphere like this. I guess it’s not very useful since we’re used to seeing half the sky unprojected, not distorted like this. And the “north pole” in our case is Polaris; not acceptable to distort it to hell like Google Mercator. OTOH we’re so used to looking at online maps this way.. Even Wikisky is using a curved projection.

Here’s a slightly fancied up plot with star names and color for brightness.

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And one more shot, this one from working Javascript code using D3 and an equirectangular projection. 5000 stars drawn (pretty much all with magnitude brighter than 6.0). The swooping band is quite distinctive; is that the Milky Way?

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And same presentation with the Mollweide projection

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