When you think of an asteroid impact, you’re probably imagining something like the cataclysmic event that nearly wiped out the dinosaurs. In an astonishingly rare event, a rock the size of the island of Manhattan could come hurtling from deep space towards Earth and destroy the world.

On the contrary, asteroids are generally leftover debris from the primordial solar system that didn’t become part of a larger body, like a planet or moon, and they’re not particularly rare. Scientists estimate that there are about 1 billion asteroids and comets classified as near-Earth objects, or NEOs. NEOs are generally much smaller than the asteroid that killed the dinosaurs. They range from weakly held-together piles of rubble 200 meters (700 feet) across, to the minuscule 2024 BX1, approximately 44 centimeters (17 inches) across. 

For several decades, astronomical surveys of the sky have looked for these asteroids. NASA’s Center for Near-Earth Object Studies (CNEOS) Fireball and Bolide Database has records of over 1,000 incidents of objects colliding with our planet since the mid-1990s. Among these is a set of 11 objects that scientists detected before they hit Earth, known as imminent impactors. Finding imminent impactors allows scientists unique opportunities to study the smallest building blocks of the solar system, enabling them to learn more about asteroid composition, structure, and history.

A team of scientists recently conducted a study on how the newly built Vera Rubin Observatory could detect more imminent impactors before they strike Earth. They examined the CNEOS Fireball and Bolide Database impact records spanning February 1, 1994, to January 1, 2026, for records of the asteroids’ coordinates, velocities, and the energy they released at the time of collision. 

They found that 343 NEOs met this criterion, including 5 known imminent impactors. Using these recorded data, they reconstructed the objects’ pre-impact characteristics. The team predicted the asteroids’ orbital paths from the recorded coordinates and velocity. Assuming the objects were spherical, they estimated the size from velocity and impact energy. From this information about the asteroids’ state before impact, the team could then simulate whether the Rubin Observatory would have detected them. 

When small asteroids hit Earth, they mostly burn up in the atmosphere, producing a bright flash that is relatively easy to spot compared to when they are in space. The Rubin Observatory can see objects up to 10 billion times dimmer than the brightest star in the night sky, Sirius. To predict if the Rubin Observatory can detect dim NEOs, the team used the solar system simulator SORCHA. SORCHA takes an observatory’s specifications and the physical properties of the NEOs and uses these to determine whether the observatory could detect them. It also estimates the measured sizes and speeds of the NEOs, and predicts when the observatory would have seen them. 

At the Rubin Observatory, an imminent impactor is considered discovered if it’s observed at least 3 separate times over 15 days before hitting Earth. So this team applied this same criterion to their simulation. They found that of their 343 impactors, SORCHA estimated that the Rubin Observatory would have discovered 14 of them before impact. 

They also found that SORCHA predicted 4 additional impactors that could have been observed at least once, potentially allowing scientists to search other telescope data for evidence of their existence in pre-collision images. Based on these results, the team estimated that the Rubin Observatory could find 4% of all objects longer than 1 meter (3 feet) before they hit Earth. This percentage of discovery translates to 1 to 2 imminent impactors detected every year, at least double their current discovery rate.

The ability to more consistently find imminent impactors would allow researchers to study the smallest pieces of the solar system in detail and to draw general conclusions about the properties of objects that could potentially collide with Earth. This would also allow scientists to more accurately calculate the orbits of imminent impactors, determine where more meteorites land to recover them, and keep tabs on the extremely rare but more hazardous large impactors for planetary defense initiatives. So, humanity can learn more about the ancient solar system, and hopefully avoid going the way of the dinosaurs while doing so!

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A new model suggests that asteroid impacts on Earth may have occasionally launched microscopic material into space that could have reached Venus’s atmosphere over billions of years. Some of this material may even have temporarily remained suspended in the planet’s cloud layers under certain conditions.

The idea is based on the theory of panspermia, which suggests that life, or the building blocks of life, can move between planets on debris created by asteroid impacts. Scientists have often discussed the possibility of microbes traveling between Earth and Mars, and even the possibility of Earthly organisms reaching locations as far away as Jupiter’s moons.

Now, interest in the possibility of microscopic life in Venus’s dense, sulfur-rich clouds has made Venus a focus for similar studies of interplanetary transfer.

A team from Arizona State University, the Johns Hopkins University Applied Physics Laboratory, and Sandia National Laboratories recently explored this idea in a study presented at the 2026 Lunar and Planetary Science Conference. They used the Venus Life Equation, a framework made in 2021 by planetary scientist Noam Izenberg and his team. This equation considers three main factors: origination, robustness, and continuity. These factors help estimate the likelihood that life exists on Venus today. If panspermia occurred, it would mean that any life on Venus, if it exists at all, would not necessarily have originated there.

A Rock Becomes a Delivery Vehicle

Before considering the possibility of life originating on Venus, the researchers first addressed a fundamental question: could any material from Earth realistically survive the journey to Venus?

When an asteroid hits Earth hard enough to send material into space, that material faces intense shock, high heat, radiation, and the vacuum of space. Studies of meteorites found on Earth show that organic compounds can survive both ejection and travel between planets. However, an important question remains: what happens when this debris enters Venus’s atmosphere at high speed?

To study this process, the researchers used the pancake model. This model helps researchers analyze how meteors break apart when they enter an atmosphere. In this model, a meteor entering Venus’s atmosphere experiences intense heating and breaks into fragments. These fragments spread out into a flattened cloud of debris called ‘cells.’ Some of these cells are small enough to stay suspended in Venus’s clouds, instead of falling to the surface, where survival would be much less likely.

The Math of Interplanetary Hitchhikers

Their calculations indicate that, depending on the assumptions used, between 2 and 4 billion cell-sized fragments may have reached the clouds of Venus. Even accounting for a 99% loss during transit, billions of cell-sized fragments could be delivered. The model further estimates that approximately 100 cells could arrive in Venus’s clouds each year, amounting to roughly 20 billion over the past billion years, which corresponds to the estimated age of Venus’s current surface.

Life on Venus?

Venus is considered a relatively low-risk target for spacecraft contamination under planetary protection guidelines. The results of this study imply that natural processes may have been transferring material from Earth to Venus for a billion years, independent of human activity.

So far, no mission has found life in Venus’s clouds. However, future astrobiology missions are expected to directly search for it. If life is discovered, these models show that scientists will then need to determine whether it originated on Venus or arrived from Earth.

Austin Burgess is a writer and researcher with a background in sales, marketing, and data analytics. He holds an MBA, a Bachelor of Science in Business Administration, and a data analytics certification. His work focuses on breaking scientific developments, with an emphasis on emerging biology, cognitive neuroscience, and archaeological discoveries.