Circling the earth aboard Friendship 7 in 1962, John Glenn had an odd encounter:

The strangest sight of all came with the very first ray of sunrise as I was crossing the Pacific toward the U.S. I was checking the instrument panel and when I looked back out the window I thought for a minute that I must have tumbled upside-down and was looking up at a new field of stars. I checked my instruments to make sure I was right-side-up. Then I looked again. There, spread as far as I could see, were literally thousands of tiny luminous objects that glowed in the black sky like fireflies. I was riding slowly through them, and the sensation was like walking backwards through a pasture where someone had waved a wand and made all the fireflies stop right where they were and glow steadily. They were greenish yellow in color, and they appeared to be about six to 10 feet apart. I seemed to be passing through them at a speed of from three to five miles an hour. They were all around me, and those nearest the capsule would occasionally move across the window as if I had slightly interrupted their flow. On the next pass I turned the capsule around so that I was looking right into the flow, and though I could see far fewer of them in the light of the rising sun, they were still there. Watching them come toward me, I felt certain they were not caused by anything emanating from the capsule. I thought perhaps I’d stumbled into the lost batch of needles the Air Force had tried to set up in orbit for communications purposes. But I could think of no reason why needles should glow like fireflies, nor did they look like needles. As far as I know, the true identity of these particles is still a mystery.

They seem to have been ice crystals, flakes of frost shed by the capsule and illuminated by the sun. Scott Carpenter saw a similar display on the next Mercury mission, Aurora 7, a few months later.

(John Glenn, “If You’re Shook Up, You Shouldn’t Be There,” Life, March 9, 1962.)

The border between the United States and Canada blurs a bit between Blaine, Wash., and Surrey, B.C. There stands the Peace Arch, a 20-meter monument to amity between the two nations commissioned by railroad executive Sam Hill in 1921.

The arch stands precisely on the border, at the center of an international park: Citizens of either nation can pass without passport or visa into the other nation’s territory, provided they don’t stray beyond a dedicated area.

The U.S. side of the arch bears the inscription “Children of a common mother,” and the Canadian side reads “Brethren dwelling together in unity.” An iron gate stands open on either side, and an inscription above reads “May these gates never be closed.”

For 88 years the Memorial Bridge carried traffic across the Piscataqua River between Portsmouth, N.H., and Kittery, Maine.

At its opening in 1923, 5-year-old Eileen Foley cut the ribbon.

In 2011, Foley, now 93, tied a ribbon at the closing ceremony.

In the interval she had served several terms as mayor of Portsmouth. “Thank you very much for this afternoon,” she said. “I will never forget it.”

(Thanks, Zach.)