Outer space is a three-ring circus sometimes. You might not see the thronging excitement—the exploding asteroids, comets, and infinite streams of debris left hurtling in their wake, a parade of centurions marching into infinity—but it’s all out there, bouncing around in space.
Sometimes though, this unseen cosmic bonanza spills over into our perceptible earthly realm: We spot a comet light up like sparklers at night, or—as happens every November—that parade of centurions comes ricocheting into town. Meteors shoot through our sky.
Autumn meteor season is already in full swing, and it’s about to get even better. The shooting stars known as the Orionids have already reached their peak and will continue sprinkling down throughout November. As they do, two more meteor showers will overlap with them, causing a cosmic circus; meteors will seem to be whipping in all directions. It may be hard to tell which shower is which.
Meteors are designated according to the constellations in space where they appear to come from. The Orionids are so-named because the point from which they seem to radiate, called the radiant, is in Orion. The groups expected to join the throng are called the South Taurids and North Taurids because their radiants are in Taurus the Bull.
To complicate things further, a fourth meteor shower will enter the picture shortly thereafter: the Leonids. Their radiant is in Leo the Lion.
Chaotic as all this seems, there’s order in the madness. Astronomers like to think they can predict when meteor showers will peak, and they can to some extent. Yet it’s a jungle in outer space; meteors are notoriously unpredictable.
Overall, we can expect both showers to sprinkle from about Oct. 20 to Dec. 10, though that’s hardly a guarantee.
Getting to spot a meteor is no less dicey, though there is some science to it. The waxing first quarter moon falling on Nov. 9 means fairly dark skies at the start of November, and dark skies are ideal for meteor spotting. Another aspect is knowing where not to look.
Don’t look to the constellation Taurus, where the radiant is located, to find meteors; from there, meteors will shoot straight toward you and, thus, you won’t see a distinct tail. A profile view will present a much more obvious target as they fly outward from the radiant point. They can appear anywhere across the heavens, so lean back on a lawn chair and take in as much open night sky as possible.
The one question still lingering is, “Where do they come from?” Scientists theorize that about 20,000 years ago, a large object orbiting in the solar system fractured into countless pieces. Some of those pieces became Comet Encke and asteroid 2004 TG10. This asteroid then shattered into countless smaller particles. When those incidentally hit Earth’s atmosphere, as they regularly do, they burn up and become Taurid meteors.
While the Taurids seem to emanate from Taurus, that’s a mere optical illusion. They’re much, much closer to Earth than the stars of Taurus, which are over 100 light-years away. The Taurids travel more or less in a parallel direction along an orbit around the sun and are relatively close to Earth. Because they travel parallel, when they fall to Earth, they look like they emanate from a single point, the radiant, similar to how train tracks travel parallel and seem to converge on the horizon. They don’t really converge; it’s a trick of perspective.
Taken together, this vast assortment of space debris was dubbed the Encke Complex, after Comet Encke. Within this complex, two great streams of particles flow in a haphazard loop around the sun, giving rise to the North Taurids and the South Taurids. As Earth orbits the sun, it plows through these two streams every late October to early December. So while there is much unpredictability in meteors, there’s also great order.
The bottom line? The ideal time to catch this cosmic fracas is early November, when the North and the South Taurid meteor showers overlap. They’ll join the Orionids and be joined by the Leonids soon thereafter. Dark skies will enhance the spectacle, courtesy of the low-key quarter moon. We can expect as many as 10 meteors per hour, so bring a wish list!