A little more than a month ago I wrote about the dieresis, two dots over a vowel that you very occasionally see in English (though more often in other languages).
The New Yorker is a high-class magazine, so I’m not entirely surprised that they had occasion to use a dieresis. Here it is:
SpaceShipTwo needed to be supple enough to break the sound barrier, light enough to reach space, strong enough to avoid breaking up on reëntry, and tough enough to make the journey once a week for years.
Stucky hadn’t heard from Dillon in almost a year, and had been desperate to reëstablish contact.
Notice how you pronounce the two “e’s” separately? That’s the function of a dieresis.
Pictures are good, so here’s a picture of SpaceShipTwo: