The Closest Stars

The Closest Stars is the latest astronomical map produced as part of Kevin Jardine’s long-running Galaxy Map project: it shows stars within 10 parsecs (32.6 light years) of our solar system. (Earlier maps covered much more territory: this map goes out to 6,000 pc.)

It’s fascinating, and has a lot of interesting information, but there’s a problem. Like all maps, it reduces three dimensions to a flat plane; as such it distorts the distance of stars that are substantially above or below the galactic plane but not very far away on the x or y axis. Take Beta Comae Berenices: it’s 9.18 pc away and as such should be at the edge of the map, but because it’s 9.18 pc away on the z axis, at nearly a right angle to the plane, it appears on the map as one of the closest stars. The distance above or below the plane is marked in parentheses, but that’s not enough: a label can’t compensate for a misleading position on the map. On the smaller-scale maps this isn’t as much of an issue, because the galaxy is more or less a disk or a lens, but within a 10-pc radius? This isn’t the right projection for the job.