I got curious about the actual names of the stars that sit on a sort of second row below the bright belt stars. The one on the left, directly below Alnitak, I see is Sigma. The one on the right, directly below Mintaka, goes by the not-very-ritzy title of 31 Orionis.
Due to the constellations not having been designed by a graphic artist or comic book illustrator or whatever, there does not happen to be a similar single star at a similar location directly below Alnilam. (Too bad, that would be really cool, it would be like Orion’s belt loops or the bottom edge of the belt or something). What there is instead — faintly visible if you’re occupied with staring into that space and trying to convince yourself there’s a second-row star there as well — is a sort of peasoup of faint stars, offset to the right of Alnilam.
Now, you’d think that for an incredibly popular constellation like Orion, there’d be oodles of annotated photographs with every! single! star! labeled. Surprisingly, there aren’t. There are broad coarse equivalents that explain that “this one up here is Betelgeuse, over here is Bellatrix”; there are telescope-weilder maps in which most of the semi-bright stars have Greek letters attached, which would be less annoying if I knew my Greek alphabet substantially better than I do, so as to ken that yonder squiggly shape on beforementioned star map is, in fact, a “sigma”. And I’ve quickly learned that there are many many different ways to enscribe a sigma or an omicron or a phi — uppercase, lowercase, script or block, artistic flair or lack thereof. But bracketing all that out of the way, the fact remains that the only one of the itsy faint starlets lurking below Alnilam that I’ve found identifies on star charts is one bearing the title VV Orionis. On some charts it shows as the fifth in an arc of about six. On other charts it looks to be the rightmost of three. They vary in how many stars they show. Which makes it hard to label on the one that I’m using. And I’m curious about the others. Look, if I can see them despite the light pollution of nearby New York City, they oughta have names!
More generally, there really ought to be a photo (preferred over star charts that draw the brigher stars LARGER which blots out nearby dimmer stars) that has a label affixed to every single star that you can see with the naked eyeball. Shouldn’t there? I mean we’re not talking Camelopardis or Draco here, this is freaking Orion. It’s practically got a posse, a fan club, a noisy cheering section.
Given that the faint ones have names like VV Orionis and 55 Orionis and even HD 36591, how freaking proper do they have to be? Yes, I would certainly think that any star that’s visible to the naked eye would have been given some kind of designation by now! You saying it ain’t true?
For purposes like this, I recommend the free planetarium software Stellarium, which is available either as a download or browser-based or a smartphone app (the latter is not free, but certainly worth it - very helpful to have it with you when you’re out observing). It gives you the view of the sky for any given day/time and location, and lets you zoom in and click on objects to obtain more information, such as magnitude. For the stars you mention, σ Orionis, 31 Orionis, and VV Orionis, it does indeed not list any proper names, only various alphanumerical catalogue designations.
Of course, I should like to add that the countless commercial “buy a star name” registries will certainly be more than happy to take your money and attach a proper name of your choosing to those stars, and have most likely done so to many customers before. Not that anyone other than these customers cares, though.
Only the brightest stars have proper names. Then you have Bayer letters (sigma Ori), and Flamsteed numbers (31 Ori), and after that some stars, including some borderline naked-eye stars, just have a designation in a catalogue. (A double letter like VV means the star is a variable.)
There are several major catalogues. One of these, with stars down to 6.5 magnitude, is the Bright Star catalogue which uses the HR prefix.
Here’s a star map of Orion’s belt with the naked-eye stars labeled.
