How to Name Your Star

Naming stars is an annoying task.  The public wishes we’d come up with something more prosaic, like “Coruscant” or “Gallifrey”*, while we astronomers get confused about names of objects.  I mean, Barnard’s Star has over 40 names (really).  So, every so often members of the public end up complaining about some giant string of letters and numbers used to identify a star, which is far from catchy.

That license plate number is, however, useful.  Astronomers don’t name stars after themselves any more. For one thing, it’s kind of narcissistic.  For another, the long “license plate number” name actually tells you something useful about the star, so that’s a distinct bonus.  When a star has even a few names, the chances are high that you won’t recognize the name another astronomer uses, so we’re stuck looking for coordinates so we can identify it as “The star at 14h 25m RA, -41d 14m DEC”.

But are there other options?

We could give every star its own individual name.  There’s some rationality behind that.  All stars move (they’re orbiting the Galaxy, after all), so after a period of time, the star at 14h25m -41d14m won’t be there any more.  Right now only a few dozen stars currently have their own names – Deneb, Altair, Regulus, Bellatrix, Betelgeuse… These are only the brightest, usually given Latin or Arabic (or Arabic-ish) names from antiquity, and there are very few additions from modern times, like Barnard’s Star, or Herschel’s Garnet Star, or Luyten’s Star.  But this would generate very long, impossible to remember lists.  And the ancients didn’t even name every star they could see with the unaided eye, to begin with… just what they considered the most important ones.

So we could try a halfway method.  Roundabout the Rennaissance, Bayer (and later, Flamsteed), invented names based on the constellation.  Bayer usually started by calling the brightest star in the constellation Alpha, the second brightest Beta, and so on… Flamsteed (and Gould) numbered the stars from east to West, again by constellation. From those two we get names like alpha Centauri, epsilon Eridani, and 61 Cygni.  This is, to some extent, easier to fit more stars in.  You even know which constellation the star is in.

Then there’s the sequential numbering method, usually used by surveys with a specific mission; often the numbers are just line numbers in the original catalog.  Sometimes they’re ordered by discovery (Barnard’s Star is the 2500th variable star identified in Ophiuchus, hence the name V2500 Ophiuchus; Wolf 359 is the 359th star discovered by Maximilian Cornelius Wolf), sometimes they’re a running number within a zone or a specific sky region(the Bonner Durchmustrung, Luyten’s star catalogs), and sometimes (most commonly) they’re sorted from east to west in Right Ascension (the Henry Draper catalog, the HIPPARCOS catalog).

These tend to work great until you find more things and need to insert new stars. Gliese’s catalog of nearby stars was particularly terrible at this; every time, he used a different method.  The 1959 catalog counted star systems from 1 – 915 in right ascension order.  In 1969, he and his collaborators added .1, .2, and .3 to the numbers to indicate that, for instance, GJ 264.1 came between 264 and 265.  Then, in 1979, the new stars merely restart the numbering at 1000 (and, for stars they were less confident were nearby, 2000).  The last update in 1991 was numbered, by other people, as just 3000 and up, and paid very little attention to star systems.

This leaves the location-based names, used by most modern surveys.  You get a horrible string of numbers, but at least it means something, to someone.  It’s the least worst option.





*Yes, I know those were names of planets.


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