The Milky Way, with Saturn the upper-right dot of light Drew Buckley/Alamy
Right now, a lot of planets are visible in the night sky. A great alignment, which occurs when all the solar system’s planets are visible at once, has just ended, but you can still spot most of them except for Mercury and Venus, which have already dipped below the horizon.
So naturally, for the past month, my phone has been dinging with friends’ pictures of the sky, accompanied by, “Hey, what planet is this?” or, “This is Mars, right?” As the designated Space Friend, I am expected to…
