One of planetary defense‘s biggest opportunities will come as the asteroid Apophis makes its tight flyby of our planet on April 13, 2029, allowing international space missions to interact with the near-Earth object. Asteroids this size only approach this close to Earth about once every 7,500 years, making the event a rare opportunity for real-world planetary defense research.

In a new paper published in the journal Space: Science & Technology, a team of researchers analyzes the many opportunities the Apophis flyby will offer for science and planetary defense.

The closest distance between Earth and Apophis during the flyby will be a mere 38,000 kilometers, about one-tenth of the distance from the Earth to the Moon. Coordinating these planetary defense efforts among the Earth’s nations may be one of the biggest challenges as the object comes uncomfortably close.

Apophis Explained

As soon as astronomers first discovered Apophis in 2004, the asteroid’s 340-meter-wide diameter and close pass by Earth immediately made it a concern for scientists. Fortunately, it is expected that on April 13, 2029, it will safely pass our planet at a distance of close to 20,000 miles—closer than some of our weather and communication satellites, but still with no risk of an impact.

Yet the near-Earth asteroid still holds mysteries for scientists. Models of the object depend heavily on assumptions, not hard data, to predict not just its tidal effects but also its composition, size, internal structure, and spin state.

With so many open questions about the asteroid and the unique opportunity to collect data and test processes for future planetary defense operations, many countries are planning missions to Apophis, but in this new paper, the researchers note that some of these activities require increased international coordination to avoid interference.

Part of the paper synthesizes known data on Apophis, including radar observations, light-curve, and spectral data. From this data, the team then developed new predictions for the asteroid’s dust ejection, orbital and spin changes, internal structural response, and surface material displacement. These projections were crucial in the researchers’ evaluations of the feasibility of various currently proposed or authorized missions and their likely scientific value.

Apophis Missions are Gearing Up

Future Apophis missions fit into four primary categories: rendezvous, flyby sample return, and impactor experiments.

In the recent research, the team found that flyby missions should capture data at very fine scales, down to the centimeter or decimeter for surface changes and hours for changes in spin period. Additionally, these space-borne instruments should be able to measure dust ejection phenomena. Together, this data stream alone could provide important direct evidence for how such rubble-pile asteroids evolve structurally. Relatively low-cost sample return missions could push this even further.

The activities coordinated under the International Asteroid Warning Network constitute the largest multinational asteroid detection and observation effort ever assembled and are its first global joint exercise. The network will build experience responding to potentially deadly space threats in the future.

Earth Interactions

On the other hand, the asteroid’s close approach to Earth will affect Apophis as well. Our planet’s gravity is expected to alter Apophis’s orbit from an Aten-type to an Apollo-type, changing the object’s spin period and orbital uncertainty. 

Additionally, roughly 1% of Apophis may experience a surface material disruption, potentially altering the object’s spectral properties by exposing fresh material.

The asteroid’s extremely low gravity may also cause it to lose surface dust to Earth’s magnetosphere, posing an electromagnetic disturbance hazard to spacecraft. Space agencies will need to monitor the situation to protect our increasingly essential space-based communications infrastructure during the event.

While there is no immediate danger to our planet, the researchers say this event is shaping up to be a pivotal moment in international space cooperation and a turning point for organized space defense.

The paper, “The Apophis Encounter in 2029: A Rare Opportunity for Planetary Science and Defense,” appeared in Space: Science & Technology on August 22, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org.

For nearly three decades, 1998 SH2 looked like a fairly ordinary near-Earth asteroid. It was discovered in 1998, catalogued, and followed through a 4½-year orbit around the Sun. Then, during a close but safe pass by Earth in August 2025, its motion refused to match the path astronomers had calculated. The explanation, announced by NASA […]

The post A Near-Earth Object Called an Asteroid for Decades Turns Out to Be a Comet appeared first on Curiosmos.

Development in space is gaining serious momentum. Impressively, NASA recently unveiled plans for a new moon base — the first concrete step toward permanently moving human civilization off Earth. However, as we […]

The post Getting ready for lunar planetary defense appeared first on SpaceNews.

A new study favors buried explosions over Hollywood-style head-on impacts.

For many years, scientists have been tracking even the tiniest fragments of space debris orbiting our planet to keep tabs on whether these small leftovers from decades of spaceflight might become a problem, whether for astronauts or for populations here on Earth.

Now, in new research, scientists say they have uncovered dozens of previously undetected fragments of space debris orbiting high above Earth, revealing a hidden population of tiny objects that some liken to a “potential minefield” in space that could pose a growing hazard to some of the world’s most important satellites.

The findings, published in the Journal of the Astronautical Sciences, were carried out by an international team led by researchers at the University of Warwick, who found 25 faint objects in geosynchronous orbit—roughly 36,000 kilometers (22,400 miles) above Earth’s equator.

Close to 80 percent of these newly detected objects had been absent from catalogs available to the public that track such debris, meaning that there could be even more unrecognized leftovers from past space missions circling the Earth than experts realize.

A Problem in Geosynchronous Orbit

Home to a steadily growing number of satellites that we rely on daily for activities here on Earth, geosynchronous orbit is where satellites that govern communication systems, television broadcasting, weather forecasting, and environmental monitoring all reside.

Objects at this altitude remain synchronized with our planet’s rotation, which means that they inhabit what is considered some of the most valuable real estate in space around the Earth.

“Pieces of space junk can be moving very quickly relative to one another, as much as several kilometers every second,” says Dr. James Blake of the University of Warwick’s Centre for Space Domain Awareness, who served as the new study’s lead author. “The energies involved are really high, and even small debris can cause a lot of damage to very expensive satellites, so small things really matter.”

Archival Imagery Reveals New Concerns

Blake and his colleagues didn’t have to collect new observations to make these discoveries: they were able to discover evidence of undocumented orbital debris simply by looking at archival images obtained by the 2.54-meter Isaac Newton Telescope in the Canary Islands.

Offering a new perspective on these archival photos, the team employed a new image processing technique known as “blind stacking,” along with advanced image-processing algorithms, to detect fragments in orbit as small as five centimeters. The detections were significant, as they are now counted among the faintest examples of debris ever observed in geosynchronous orbit.

Naturally, a question arises: how many more examples of tiny debris might be lurking up there?

Tiny Tumbling Troublemakers in Space

Additional analysis of the brightness of these objects revealed another concerning reality: based on variances in the light they reflect, it was evident that many of these objects are tumbling as they make their way through space.

The team’s findings offer a wakeup call in terms of just how much undetected debris may be drifting—or even tumbling—through geosynchronous orbit. However, there is also a positive side to the situation: the team’s discoveries also showcase our growing ability to make such detections if we know how to look for such minuscule objects.

Still, the findings underscore the challenges presented by monitoring orbital debris in a space above the Earth where such materials could potentially linger for centuries, since atmospheric drag in this region of orbit is essentially nonexistent.

“The debris in the neighborhood of the geostationary belt is a potential minefield,” said co-author Dr. Stuart Eves of SJE Space Ltd. “No one in their right mind would enter a terrestrial minefield without a mine detector. Similarly, no one in their right mind should launch a satellite to GEO without an adequate debris survey.”

A Call for International Collaboration

With the project’s reach beyond Europe to include collaboration with researchers in Australia and Japan, the team says that international cooperation will be necessary to track potentially dangerous orbital debris—especially as more and more satellites are being placed in orbit above the Earth.

Increasingly sensitive surveys will be essential for understanding and mitigating the risks posed by even the smallest fragments of space junk, the team says.

“There are a finite number of orbital slots in the GEO belt,” Blake adds, “so it’s important that we know how much debris is out there, how it behaves, what risks are posed to the active satellites we rely on. Surveys for faint debris help us build a clearer picture.”

The team’s findings were detailed in a new study, “DebrisWatch II: Digging Deeper for Geosynchronous Debris,” which appeared in The Journal of the Astronautical Sciences.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

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!

The post How many asteroids can we detect before they hit Earth? appeared first on Sciworthy.

During future space missions, humans may finally encounter extraterrestrial life forms, settling the age-old question of whether we are alone in the cosmos. But what if alien biology is so different from that of Earthlings that its presence could become a potential global hazard?

This is the concern raised by researchers Frederick I. Moxley and Anthony Ricciardi in a new study, which argues that in an era of sample return missions and space missions that are carrying humans and our robotic probes farther into the cosmos than ever before, we need to be prepared to enact measures to protect our planet against the unforeseen consequences of any potential alien encounters the future may hold.

“The advancement of space exploration into an era of sample return missions from Mars, asteroids, and icy moons raises the potential for biological contamination either to or from Earth,” the authors write in their recent study, published in the journal Ambio. Given the potential for such contamination, Moxley and Ricciardi approach the question of alien contact from the perspective of past examples where invasive species on Earth have caused major disturbances to the environments they encounter.

“We consider the possibility that extraterrestrial organisms introduced to Earth could behave analogously to invasive species by destabilizing ecosystems or interacting unpredictably with their new environment,” the authors write, pointing to the multitude of examples known to science, many of which involve the introduction of microbial organisms into new environments—often with devastating consequences.

In many cases, such organisms not only can survive in new environments, but can often adapt with remarkable speed, even in some of the most extreme environments.

This, the authors say, challenges the idea that extraterrestrial life might not even be capable of surviving on Earth, as expressed by some past research.

“The plausibility of encountering extraterrestrial life warrants stringent planetary protection measures grounded in biosafety and biosecurity principles,” the authors warn.

So how do they suggest protecting Earth against such potentially catastrophic events involving future encounters with extraterrestrials?

According to Moxley and Ricciardi, building a quarantine facility on the Moon could serve as Earth’s last line of defense against any unintended alien invasions that could radically disrupt Earth’s fragile ecosystems.

“Due to its proximity, natural isolation, and apparent lack of a biosphere, the Moon can serve as a secure site for biocontainment of extraterrestrial samples,” the authors write. In their study, they examine historical instances where biological invasions have led to catastrophic environmental changes and argue that constructing a biocontainment facility on the Moon “should form the cornerstone of modern astrobiological risk mitigation strategies.”

What the researchers propose falls in line with current plans NASA has for a permanent lunar base, which is one of the many ambitious efforts under its Artemis Mission. Such a lunar outpost, which will serve as the official Artemis Base Camp, is planned for construction near the Moon’s South Pole.

At a cost of close to $30 billion, the effort will help to facilitate an ongoing human presence on the Moon by as soon as 2028, according to current mission timelines, and will serve as a science hub in support of future lunar exploration.

For Moxley and Ricciardi, incorporating a quarantine facility within our future lunar infrastructure that can house any extraterrestrial life forms we may encounter could prove to be vital. Ultimately, having such a facility may play the important role of shielding Earth against unintentional contamination by a potentially invasive alien species.

The team’s recent paper, “Protecting earth from extraterrestrial contamination: The case for a lunar biocontainment facility,” was published in Ambio.

Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.

From high-speed battering rams to gravity tractors, the technology exists to protect the planet. The question is whether humanity will act in time — and in concert.