Centering

I mentioned separable verbs before, but I ran into two nice examples of correct and incorrect usage of the same verb, so here you go.

The verb is “to center on.” It’s transitive, so you have to have a direct object. You center on something. So:

The filter uses dual etalons in a double stack configuration (40mm external and 20mm internal) to provide a very narrow <0.5 Ångstrom passband, centered on the 6562.8 Ångstrom H-Alpha line.

It’s a telescope that you can look at the sun through. I have a similar one (with only the internal etalon). Stop by sometime during the day and I’ll get it out and let you look through it. You can see solar prominences around the edge of the sun. Pretty interesting. If you want to buy one like mine for yourself, go here. It’s a little less expensive than the one in the picture.

Now here’s now not to use that verb:

Virgin Galactic’s resurrected dreams of private spaceflight following the crash in 2014 centers around SpaceShipTwo.

That sentence was written about Virgin Galactic, not by them, so no discredit to VG. But the center is a point. You center on that point. If you want to go around, use rotate or revolve.

Using this verb correctly is one of those little things that not a lot of people notice, but doing so improves your writing.

Then there’s the verb “center” all by itself. Used that way, it’s some sort of new age thing meaning to concentrate on one idea, or something like that.