The positions of stars on the celestial sphere are known to excruciating precision, but their distances only crudely, and only for the most nearby stars. However, the new satellite astrometry has provided us with very good distance information for stars, and this data is all available for free in machine-readable form.

It is now possible for star charts to be compiled where not only its position in RA and Dec are accurately plotted, but its distance in parsecs or light years. This information could be coded in some form of virtual reality display, so you could “fly” through our corner of the galaxy. Or alternatively, even a traditional paper map could be printed in which the distance of the star from Earth could be indicated by dot size, shape, color or some other symbol; or even by some sort of anaglyph optics.

It would not be possible to display the “r” dimension to the same precision as the RA and Dec, but with a little practice, one could train oneself to see nearby galactic space in three dimensions. Surely, by harnessing the power of the human visual system to detect patterns, this might reveal relationships and structures that would not be apparent from raw tabular catalogue listings, or even the most sophisticated pattern recognition algorithms.

By cross-referencing some common catalogues such as the HabCat data (see post below) or the Gliese Nearby Stars Catalogue with the Tyco and Hipparchos data bases very detailed and complete maps of nearby space (several hundred parsecs) could be devised. Most ordinary star charts woefully under-represent faint nearby stars (by far the most common), and favor the display of very bright stars at huge distances. This gives us a distorted idea of what our neighborhood looks like, and its stellar populations.

A chart of this type would be of great value to SETI investigators, deep space mission planners—and science fiction writers!