Every night on Earth, thousands of automated stargazers wait to take pictures of shooting stars. I’m one of the scientists studying these meteors.
Most movies and news stories focus on large asteroids that could destroy Earth. And every few months, my phone alerts me that an object the width of nine washing machines is about to narrowly whiz by. But the tiny bits of dust and debris that enter our atmosphere every day tell an equally interesting story.
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A study published in March 2026 searched through millions of meteor observations collected by an all-sky camera network based in Canada, Japan, California, and Europe and discovered small, recently formed star clusters. The 282 meteors associated with this cluster tell the story of an asteroid that flew a little too close to the Sun.
meteor formation
When a sand-sized piece of space rock hits the atmosphere, it heats up almost instantly, causing the surface layer to evaporate and turn into electrically charged gas. The entire shard begins to glow. This is called a meteor. If the object is large and bright, like a rock, it is called a fireball or fireball. On average, these objects hit the atmosphere at more than 15 miles per second. For small dust or sand-sized objects, the entire process only takes a few seconds to completely disappear.
Most of these sand-sized debris in our solar system originate from comets, cold icy objects from the outer edge of our solar system. When a comet passes close to the Sun, its icy components turn into gas and a large amount of dust is emitted. This is why comets are often called “dirty snowballs” and appear blurry in telescope images.
Asteroids, on the other hand, are remnants of the early solar system that formed near the sun. They are dry and rocky, lacking the ice that forms comets’ characteristic tails.
What does it mean to be active?
Astronomers refer to asteroids or comets that emit dust, gas, or larger debris as “active.” This activity is caused by some external force on the object in space, such as heat from the sun, a small shock, or when an asteroid spins too fast and flies off.
Understanding and identifying activity helps scientists better understand how these objects change over time.
For comets, ice sublimation (when solid ice sheds its liquid phase and turns directly into gas) is the main culprit. However, for asteroids, the reasons for activity can be very different.
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For example, NASA’s OSIRIS-REx mission, launched into space to study an asteroid named Bennu, observed activity from the surface with heat stress and small shocks as the main explanations.
Other causes of asteroid activity include breaking up when an asteroid spins too fast, tearing the asteroid apart due to tidal forces during a close encounter with a planet, and outgassing.
Researchers most commonly use telescopes to explore activity. Astronomers can look for “tails” or obscurities around objects. This tail clearly indicates that there is gas or dust around the body. But there is another way to look for activity: meteor showers.
Find hidden asteroids from meteor showers
The most famous active asteroid is 3200 Phaethon. It is the parent object of the Geminid meteor shower that occurs in mid-December every year. During its past close encounters with the Sun, Phaethon ejected vast amounts of dust and larger debris. Over time, some of these Phaethons spread out along their entire orbits, leading to the current Geminid meteor shower.
The meteor showers we observe occur when Earth passes through one of these streams of debris. So if astronomers can detect meteor showers, they can also use them to find active objects in the universe.
Initially, the debris ejected by an asteroid or comet moves closer to each other. Imagine squeezing a drop of food coloring into a flowing stream of water. Initially, the pigment remains in a densely concentrated cloud. However, as it flows, the swirls of water pull the dye, causing it to spread and fade.
In space, the gravitational pull from passing planets acts like their currents. They tug on individual meteor fragments in slightly different ways, gradually pulling the once-tight stream apart until they completely dissolve into the solar system’s background dust.
Discovery of a rocky comet
In a study published in the Astrophysical Journal in March 2026, I used observations of millions of meteors to search for recent unknown activity from near-Earth asteroids. I found one clearly noticeable cluster of 282 meteors.
What makes this discovery so exciting is that we are essentially witnessing a hidden asteroid being burned to pieces. This newly identified meteor shower follows an extreme orbit that brings it nearly five times closer to the sun than Earth.
Based on how these meteors break up when they hit the atmosphere, we find that they are moderately fragile, but more durable than those from comets. The discovery shows that the intense heat of the sun literally cracks the asteroid’s surface, baking out the trapped gas and causing it to collapse. This is probably the main cause of past phaetonic activity, and the main reason why meteorites on Earth are so diverse.
Search source
Why is finding hidden, crumbling asteroids important? Meteor observations act as uniquely sensitive probes that allow us to study celestial objects that are completely invisible to traditional telescopes.
Analyzing this debris not only helps solve astronomical mysteries, but also helps us understand the physical evolution of asteroids and comets in our solar system. More importantly, it will reveal hidden populations of asteroids near Earth, which will provide important information for planetary defense.
The parent asteroid of the new meteor shower remains elusive. But NASA’s NEO Surveyor mission, set to launch in 2027, offers a promising solution. This space telescope is specialized in planetary defense and finding dark and dangerous asteroids approaching the sun, making it an ideal tool for exploring the origins of the show.
This edited article is republished from The Conversation under a Creative Commons license. Read the original article.
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