The Starry Night

Very early in the voyage many of us developed the habit of having some ice cream after dinner (where do they keep so much ice cream?) and going out on deck to watch the sunset. This habit continues, unbroken, through the third week at sea. The sunsets are usually quite beautiful, but this marks only the beginning of our nightly ritual.

Sometimes before the sun even sets, we can see Venus, alone in the brass-colored western sky. Then Sirius, the Dog Star, appears nearly straight overhead. As the sky turns from brass to lavender to cobalt, more and more stars seem to jump out of the sky. Procyon is next, then Rigel, Canopus, Betelgeuse, Aldebaran, Capella, Castor, Pollux, Regulus… it turns out you can learn a lot of star names when you can’t easily check email or read the news. The satellite internet connection makes it feel like 1995.

Speaking of satellites, we regularly see satellites silently sailing across the evening and morning skies. They have no lights of their own, but they shine in the sunlight. Sometimes they are dim, so dim that we can’t see them when we look directly at them. Sometimes we see them “flare,” when the large, mirror-like solar panels catch the sunlight at just the right angle to reflect it toward us—like using your watch to annoy the teacher. When this happens, for just a second or two, the satellite becomes the brightest object in the sky. Occasionally we see one flash quickly, again and again, perhaps a defunct satellite that is no longer able to maintain its orientation. And a couple of times, we’ve seen the International Space Station. The ISS is extremely bright, and remains so for a few minutes until it disappears into the horizon or slips into Earth’s shadow. The knowledge that there are humans aboard that brightest of stars is truly awesome. The realization that those humans (at only a few hundred miles away) are probably closer to us than any people on Earth’s surface is humbling.

We have seen two ships and just one aircraft since our second day at sea, three weeks ago now. The ship has few lights outside, because those who pilot the ship at night need their night vision to look for obstacles. This near-total darkness makes for perfect stargazing conditions. On clear nights, there are so many stars that it becomes difficult for us to identify constellations! But the night sky is filled with so much more than constellations.

We can clearly see the Milky Way, the spiral galaxy that contains our small solar system. Just as the planets orbit the sun, everything in the galaxy orbits an enormous black hole at the center of the Milky Way. If you look toward the center of the galaxy, in the direction of the constellation Sagittarius, the Milky Way is absolutely spectacular—a strip of foggy white, partially obscured by dark clouds. These clouds aren’t Earthly clouds, though: they are vast shrouds within the galaxy itself, called molecular clouds. These huge regions of interstellar dust and molecular hydrogen are the fertile grounds where stars are born. We can also see the Large Magellanic Cloud, a small satellite galaxy that neighbors the Milky Way, and at ~150,000 light-years, it is one of the most distant objects visible with the naked eye.

With just a pair of binoculars that we found in the ship’s conference room, we can see so much more! Nebulae are either regions where stars are formed (look for Orion’s sword) or where they recently died in a supernova (look for the Crab Nebula). Dozens of globular clusters, tight groups of stars, dot the night sky (the most famous is the Pleiades).

Early one morning, we could see through the binoculars all the Galilean moons—the four moons of Jupiter that Galileo saw more than 400 years ago (Io, Europa, Ganymede, Callisto). The early morning is also the best time to look for shooting stars. The Lyrid meteor shower peaked just a few days ago, so for the last week we’ve been seeing 10 or more shooting stars every morning. A few of us were particularly lucky to catch a large meteor, so large that we saw it break up into smaller chunks as it disintegrated in its descent.

As dawn approaches, we see the Zodiacal Light: sunlight scattering off of dust in the plane of the solar system. This hazy finger reaches upward along the ecliptic, the imaginary circle along which the sun, the moon, and all of the planets move, and where the constellations of the Zodiac lie. Finally, Mercury appears on the horizon, and sunrise is upon us. We will begin the ritual again with ice cream this evening!

— William Hawley

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