In a favorite artwork of mine, Adrian Tomine’s drawing “Missed Connection,” two people look up from their reading to see that they are holding the same book—tragically, their eyes meet through the chance alignment of two passing subway cars, a moment before their respective trains pull away in opposite directions, never to meet again. These two haggard commuters, each holding a book that could have been the source of a meet-cute they’d tell friends about for years, are instead about to remember the moment they were so close but separate. The drawing is suffused with the visceral rumble of trains pulling away from each other, a beginning and ending all in one.
On the evening of Dec. 21, stargazers will have a moment to savor a similarly perfect, bittersweet moment in the sky: the Great Conjunction of Jupiter and Saturn. Just after sunset on Monday, the two largest planets in our solar system will appear closer to one another than they have in more than 800 years. These celestial giants will still be quite far from one another in space—some 400 million miles apart—as they each circle the sun in their individual orbits. And much like two trains looping the sun on adjacent tracks, Jupiter and Saturn pass one another fairly regularly (every 20 years or so). But the visibility of their alignment in the sky depends on our point of view here on Earth. What makes it even more rare is that it will actually be dark enough to see them: For the past 800 years, the Great Conjunction has also been closely lined up with the sun, making it nearly impossible for humans to see.
This Monday evening, however, Jupiter and Saturn will be glittering brightly in the southwestern night sky just after sunset—if you have a clear view toward the horizon, you will see them sparkling low in the sky as darkness falls. What’s more, you can see this momentous passing with your own eyes, and no equipment: Jupiter and Saturn look like bright stars, and they will be visibly very close to one another. They won’t quite merge or appear to touch—they’ll still be slimly separated by a tenth of a degree, or less than the width of your pinky finger held at arm’s length. Some have compared the sight to a tipped-over snowman, which as we all end a terrible year in a heap of exhaustion, is one of the more relatable stargazing metaphors I’ve heard in a while. If you do happen to have a pair of binoculars or a small telescope, you might be able to make out Jupiter’s closest moons, pinpricks of lights hovering near the giant planet, or perhaps the elongation of Saturn’s rings (which Galileo thought looked like ears)—but all of that is purely a bonus round to the Great Conjunction itself, which will be clearly visible to the naked eye.
Jupiter and Saturn’s very special chance meeting will also take place on a significant day of the year: the solstice. Here in the northern hemisphere, Dec. 21 marks the shortest day of the year (or the longest night, depending on your level of 2020 despair). As we move into northern winter, the tilt of the Earth makes the sun hang low in the sky, giving us only the feeble slanting rays we associate with the colder months. In what has been an especially hard year already, the media is full of recommendations for bright lamps to combat seasonal affective disorder, the heavy snow of depression that lays over so many of us this time of year. But the winter solstice is more than its scarce daylight—it’s also a turning point. After the solstice, the days grow gradually brighter, the sun rises higher in the sky, and we begin our progression toward spring.
The last time the Great Conjunction was similarly visible, in the year 1226, such celestial events were taken to be either worrying or auspicious. While in 2020, we understand the nature of planets and their orbital dynamics enough to technically demystify the Great Conjunction, it’s still hard not to feel that it’s somehow portentous. No matter how high the sun reached in the sky this year, 2020 has been dark and chaotic. Separated from our friends, loved ones, and in many cases the casual interactions of public space, we’ve spoken of bubbles, screens, distance, being “Zoomed out.” Even the two people locking eyes in Tomine’s “Missed Connection” look deliciously close—public transit without masks, even if they are in separate trains!—when compared with how this year has fractured us. For me, and many of the people I know, we are tumbling toward 2021 in shambles.
The portent in the Great Conjunction, though, is perhaps not so mysterious at all: Even as I write this, the first doses of coronavirus vaccines are being administered around the world. Though it will likely be a long time until we are able to resume anything close to life as we knew it, we can take comfort in the light of elongating days, as our own Earth moves inexorably forward in its path towards spring. Despite our continued physical separation from one another, we have a moment on Monday to collectively look up, and together see an event that no human has witnessed for 800 years. Given that the next such Great Conjunction won’t happen until 2080, Monday’s will be a once-in-a-lifetime sight for most people. (However, even if you miss the two planets’ closest proximity on Monday evening, you’ll still be able to watch them drift apart in the coming days.) In this shared moment, we can pause to mark the alignment of these two giant planets, shining to remind us of the ephemerality of everything, and that time is moving us ever forward to a future where we will be together in space again.
See you at the next stop.
Future Tense is a partnership of Slate, New America, and Arizona State University that examines emerging technologies, public policy, and society.
from Slate Magazine https://ift.tt/2WwLF1I
via IFTTT
沒有留言:
張貼留言