The planet Mercury is small, not much larger than our moon, but dense, mostly a molten iron core with hardly any crust or atmosphere. It flies fast, orbiting the sun once every 87.97 earth days, and spins slowly, rotating only 1.5 times every trip around. During those long nights and days, temperatures drop to minus 280 degrees Fahrenheit and rise to 800 degrees. The poles, surprisingly, contain deposits of ice, but the rest of Mercury’s surface is rough ground, a record of the early years of the solar system, when the planet was pummeled by asteroids and meteors.

All the craters are named for artists. Shakespeare, John Lennon and Walt Disney are there. Alvin Ailey is too, as are Bach, Basho, the Brontës, Hemingway, Faulkner, Kahlil Gibran, Michelangelo and 361 others, all cataloged in “The Gazetteer and Atlas of Astronomy.” The planet is a hot, fast, magnetic monument to earthly imagination.

On Jan. 21, at 10:54 a.m. Eastern Time, Mercury will begin its first pass by Earth of the new year. For about three weeks, it will appear to move backward across our sky and will, according to astrologers, disrupt technology, communication and human concord. Facebook and Twitter will clog with reports of appointments missed, important email sent to the spam folder, wars between nations, cars crashed and iPhones dropped in toilets, all followed by some version of the hashtag “#mercuryretrograde.” Advice from astrology blogs will arrive in unison: Back up your computer, expect miscommunications, don’t make agreements or important decisions and don’t sign contracts — and hide.

The belief that the movements of celestial bodies govern our lives is more popular in the United States than it has been in two decades, according to a recent National Science Foundation report. In a 2012 survey, a third of Americans viewed astrology as “sort of scientific” and another 10 percent as “very scientific.” Belief is most prevalent among 18-to-24-year-olds but has markedly increased among 35-to-44-year-olds in recent years. To put this in perspective: More Americans believe in astrology, or “sort of” believe in astrology, than believe that climate change is influenced by the burning of fossil fuels.