The sudden flash of a shooting star is a delight, and its luster isn’t dimmed by the knowledge that meteor showers are merely the visible manifestation of space dust.
If there’s a clear sky on Sunday, December 13, odds are good for spotting the spectacular meteor shower known as the Geminids. In this issue, astronomer and writer Ken Croswell explains the many mysteries surrounding the Geminids’ flamboyant display, including that they have the rare distinction of being a meteor shower spawned by a lowly asteroid, rather than a stylish comet.
Scientists have known for over 100 years that comets can spark meteor showers, but it wasn’t until 1983 that researchers had the technology needed to connect the Geminids to a small asteroid, dubbed Phaethon because it swings so close to the sun. Decades later, scientists are still trying to figure out just how Phaethon provides such a dazzling show.
While you’re in the backyard looking for meteors, it’s the ideal time to also scan the skies for Betelgeuse, the massive red star in the constellation Orion. (You can catch a glimpse of it on the right side of our cover image.) Wintertime means Orion has returned to the evening sky in the Northern Hemisphere, and it comforts me to see Betelgeuse glowing on Orion’s shoulder. But last year, that star was at the center of an international commotion. Betelgeuse suddenly dimmed — did this mean the aging star was about to explode in a supernova? Stargazers, professionals and amateurs alike, rushed to the telescopes.
Betelgeuse is still with us, having returned to its former brightness earlier this year. But astronomers remain at odds over the cause of its sudden swoon. Some think that the star was obscured by its own dust, while others dis the dust hypothesis. As Science News astronomy writer Lisa Grossman reports, shutdowns of major telescopes as a safety measure during the pandemic have stymied efforts to solve the mystery of the dimming star. That’s frustrating for researchers, in part because the answer could help shed light on the origins of life in the universe.
Ready for one more celestial riddle? Flip to Page 10, where we update you on the latest from STEVE. The unusual sky glow’s mauve arc looks a bit like an aurora, but isn’t. Ditto for STEVE’s bright green “picket fence,” researchers now say. “It’s really weird, and nobody really knows what’s going on just yet,” Boston University engineer Joshua Semeter told Science News staff writer Maria Temming.
These celestial conundrums remind us just how strange and wonderful the cosmos remains, despite humankind’s best efforts to figure it all out. More delightful mysteries, please. And back on Earth, we’re hard at work wrapping up our year-end special issue. It’s not hard to guess what we picked as the biggest science story of 2020. But there was plenty else going on, and we spent many hours debating which discoveries or disputations merit inclusion. What would you choose? Write us at [email protected] with your picks for the big science news of 2020. I’m looking forward to seeing your choices.