Gaia and Bajor

Recently, the first data from the GAIA star mapping mission was released. Astronomers have their first chance to look at the new and much more accurate information. My first thought was: “Star Trek maps!”

This is only a “taster.” Despite over a billion stars having been identified, not all of these stars have all the information available about them at this stage. The things I noticed is that this release of data has no stars less than eleven light years from Earth, and very few of the brighter stars are included. Even so, I decided to do a “mash-up” of the new data, with the HYG database ofstars prepared by David Nash at The Astronomy Nexus website.

I was trying to construct a map of Cardassian and Bajoran space, so I adjusted the coordinates so that the “zero point” of the x, y and z axes would be close to both systems. Although it’s strictly unofficial, real stars in the Hipparcos catalogue can be matched with the places Geoffrey Mandel put the two stars in the Star Trek Star Charts. HIP 63584 is “Cardassia” and HIP 62527 is “Bajor.”

They’re both about 100 light years “above” Earth in the system of galactic coordinates, and away off to one side. Because of the Deep Space Nine Technical Manual map it’s meant to resemble, the twenty light years on a side sector grid is a vital aspect of the map, and is fixed by the position of the Earth and the galactic coordinates. So I used Astrosynthesis to generate a map:

SmallCardxy1.png

Oh. “Cardassia” isn’t in the new dataset, so it’s still at the position set in the HYG database. “Bajor” is now where GAIA says it is, and it’s not in the right place. There is still some “wiggle room,” but nowhere near enough. GAIA claims to have fixed the parallax (the distance away the star is, to oversimplify things) to better than 99% accuracy for most of the nearer stars (this specific one included), and certainly the margin for error in the GAIA stars is impressively small, as far as I can see. In practice, “Bajor” is sitting in the centre of a line two light years long that passes on a direct line through the star in the direction of Earth. Because of the angle, it’s not even the full distance of one of the small light-year-on-a-side squares on my map.

Naturally, if you just accept that outer space in ”Star Trek” only approximates to the real universe, or even has nothing whatsoever to do with it, then there’s no problem at all. It makes the whole idea of star maps less interesting, though. You can just put the stars wherever you like, and if my map ends up looking nothing like yours there’s no possible way of choosing between them.

The good news is that there will be a much more detailed set of GAIA data along next year. I’m looking forward to pulling the data off the Vizier service and trying to match up the real stars mentioned in ”Star Trek” and some of the fan identifications. I’ll also be constructing some maps of roughly the right bit of the Alpha Quadrant, and trying to find a pair of stars that look vaguely right. I’m not sure how well that will go, but I can be reasonably certain that if I am successful, the star positions will be fixed accurately enough for me not to have to worry that they might shift out of position again.

In the longer term, GAIA should allow for the construction of accurate star maps of the whole nearby Galaxy, out to about 1,000 light years (if you can handle the amount of data), complete with details about the components of the multiple star systems. Even if that turns out to be a bit optimistic (and it really shouldn’t), it’ll still be a huge leap forwards for real astronomy and not just science-fiction star mappers.


Base Maps

by StrauchiusStrauchius on 07 Nov 2016 09:56, last updated on 07 Nov 2016 10:00