Those Halloween fireballs might be more dangerous than you think

Meteors appear as glowing streaks when tiny bits of dust, pebbles, or rock burn up while entering Earth's atmosphere. The Taurid meteors come from debris left behind by Comet Encke, which circles the sun and sheds a stream of material along its path. Twice each year, Earth moves through this debris field -- once near Halloween, when the Taurids light up the night, and again in June, when the Beta Taurids occur during daylight hours. Those June meteors are rarely visible unless they produce exceptionally bright fireballs.

A Question of Risk: What If Larger Taurids Came Close?

Scientists have long studied the Taurid stream, but a recent study led by Research Professor Mark Boslough takes a closer look at its potential hazards. The paper, published in Acta Astronautica as part of the Planetary Defense Conference proceedings in Cape Town, South Africa, is titled "2032 and 2036 risk enhancement from NEOs in the Taurid stream: Is there a significant coherent component to impact risk?" The research examines whether the Taurid stream could increase the likelihood of impacts from near-Earth objects (NEOs) in coming decades.

"Planetary defense is the multidisciplinary and internationally coordinated effort to protect the Earth and its inhabitants from impacts by near-Earth objects (NEOs)," said Boslough. "It requires surveys to discover and track NEOs, campaigns to characterize those that are hazardous, modeling efforts to understand and predict impact effects and associated consequences, and mitigation through impact avoidance and/or civil defense."

NEOs include asteroids, comets, and fragments whose orbits bring them close to Earth's path around the sun. While small particles like those in the Taurid meteor shower enter the atmosphere all the time, larger bodies capable of producing events like the 2013 Chelyabinsk explosion or the 1908 Tunguska blast are much rarer.

Studying the Taurid Stream and Airburst Hazards

Boslough's research incorporated new data from Taurid observation campaigns. The results suggest that small near-Earth objects capable of producing atmospheric explosions, known as airbursts, may pose a higher-than-expected risk. The study also examined the potential existence of a "Taurid resonant swarm" (TRS), a cluster of debris objects influenced by Jupiter's gravity.

"The resonant swarm is theoretical, but there is some evidence that a sparse swarm of small objects exists because bright fireballs and seismic signatures of impacts on the moon have been observed at times that the theory has predicted," Boslough explained.

Objects in the Taurid stream orbit the sun seven times for every two orbits of Jupiter. This pattern, called resonance, means the stream aligns with Jupiter at consistent intervals. The planet's powerful gravity can pull fragments together, creating dense groupings -- much like swirling gold particles collecting in a prospector's pan.

Future Close Approaches: 2032 and 2036

If the Taurid swarm exists, it is expected to pass close to Earth in 2032 and 2036, possibly increasing the risk of impacts during those years.

"Our findings are that we have the technology to test the Taurid resonant swarm by using existing telescopes for targeted sky surveys in 2032 and 2036 when the hypothetical swarm will make very close approaches," said Boslough.

These objects, if present, would likely be visible to telescopes as they move away after missing Earth. Concentrations of larger bodies -- similar in size to the Chelyabinsk or Tunguska impactors -- could potentially be observed during those windows.

During his time at Sandia National Laboratories (SNL), Boslough modeled the Chelyabinsk explosion, estimating the object to be roughly 60 feet wide with an explosive force of about half a megaton of TNT. The Tunguska blast was likely 10 times more powerful, releasing an estimated 3 to 5 megatons.

"If we discover the objects with enough warning time, then we can take measures to reduce or eliminate the risk. If the new infrared telescope (NEO Surveyor) is in operation, then we can potentially have much more warning time," he said.

The research was supported by NASA at the University of New Mexico and by the National Nuclear Security Administration (NNSA) at Los Alamos National Laboratory as part of its planetary defense efforts.

Preparedness and Public Awareness

Boslough encourages the public to stay informed about natural hazards of all kinds -- including weather, fire, earthquakes, and volcanoes -- and to maintain perspective.

"Asteroid impacts represent a small but significant risk, and New Mexico's national labs have some of the best minds working on the problem," he said.

One takeaway from the Chelyabinsk event is that most injuries were caused by shattered glass when people ran to windows to watch the bright flash. Boslough notes that the same pattern would likely occur if a similar airburst happened over New Mexico. Experts recommend staying away from windows and not looking directly at the blast.

What to Expect From the Next Taurid Swarm

The 2032 approach of the hypothetical swarm will come from the nighttime side of Earth, making any potential objects easier to observe. Boslough says that if a significant concentration exists, the probability of an airburst or impact could be higher than normal, though the overall chance remains very low.

Daytime fireballs also occur, but they must be extremely bright to be visible against sunlight. "The average probability is extremely low, so even an enhanced risk means that the probability would still be low. The swarm will come from the direction of the sun in 2036, so fireballs will not be seen in our blue skies unless they are extremely bright," Boslough said.

Fighting Misinformation About Impacts

The Magdalena Ridge Observatory near Socorro participates in planetary defense observations, and both Sandia and Los Alamos have active programs. Boslough cautions people to be skeptical of misinformation.

"A lot of false information and mythology about this subject has been promulgated on social media, online sources, and sensational TV shows. This media gives the public the wrong impression about NEOs, impacts, and airbursts, and what we can do to reduce the risk," he said.

He has also worked to correct false claims in the scientific record. His published research helped prompt a journal to retract a paper that incorrectly suggested an ancient city in Jordan was destroyed by a Tunguska-scale airburst. He also coauthored a detailed refutation of the theory that the Taurid swarm caused a global climate disaster 12,900 years ago.

When and How to Watch the Taurids

For those hoping to catch the Taurid meteor shower this year, Boslough recommends looking up after 2 a.m. on Halloween night when the moon is below the horizon. A few days after the next full moon on November 5, the Taurids should again be visible in the evening sky before moonrise.