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Spot-3 Earth Observation satellite.
Image credit: CNES

Yet another “close call/near miss” in Earth orbit.

On Christmas Day 2025, a European non-operational payload (SPOT 3) passed within roughly 65 feet (20 meters) of a fragment from a Soviet payload that exploded in 1996.

“This conjunction involved two objects left in orbit last century,” said Darren McKnight, a senior technical fellow for LeoLabs that offers persistent orbital intelligence for space domain awareness.

Cosmic culprits

SPOT 3 (Satellite pour l’Observation de la Terre) was a commercial Earth-imaging satellite from CNES (Centre National D’Etudes Spatiales), the French Space Agency. It was launched on September 26, 1993 and ceased operations after a malfunction in November 1996.

The other object was a fragment of the former Soviet Union’s Cosmos 1275 that was launched and then broke apart in 1981, with the break-up occurring at approximately 609 miles (980 kilometers).

Image credit: LeoLabs

Two-body problem

The actual near two-body bang-up was at roughly 525 miles (845 kilometers) altitude.

According to a History of On-orbit Satellite Fragmentations, 16th Edition, produced by NASA’s Orbital Debris Program Office, the Soviet Cosmos 1275 is the only member of its class, Parus, to explosively fragment.

Image credit: History of On-orbit Satellite Fragmentations, 16th Edition

The defunct spacecraft was a member of a Soviet military navigation system called the Parus series. The satellite was only 50 days old at the time of the event.

“During the February 1992 Space Debris Conference in Moscow, Russian analysts discussed independent studies about the probable cause of the breakup. Later, the official Russian assessment asserted that a battery malfunction was the likely culprit,” the NASA document explains.

PC factor

Often, probability of collision (PC) drops as time of closest approach (TCA) is approached, “however, it stayed very stable for this event,” McKnight adds.

“When an eventual collision occurs,” McKnight said, it will likely look like this PC/miss distance evolution (see LeoLabs chart).

Image credit: Darren McKnight/LeoLabs

Image credit: ULA

 

 

The countdown for the Artemis II wet dress rehearsal is underway at NASA’s Kennedy Space Center in Florida.

The countdown clock began January 31 at 8:13 p.m. EST, or L-48 hours, 40 minutes before the opening of a simulated launch window at 9 pm. Mon, Feb. 2. The test is expected to go until approximately 1 a.m. Feb. 3.

 

 

 

 

 

 

Go to NASA’s Artemis II Live Views from Kennedy Space Center at:

 

Image credit: Mars Guy/NASA/JPL-Caltech

Mars Guy details how driving a rover on Mars requires humans on Earth to plan the route.

“Self-driving cars on Earth can take advantage of GPS to navigate,” Mars Guy points out, “but Mars has no global positioning system, so rover drivers have to set waypoints manually.”

Image credit: Mars Guy/NASA/JPL-Caltech

AI navigation

Now Artificial Intelligence (AI) has been given that task. See how NASA’s Perseverance rover was AI navigated across Martian terrain!

This Mars Guy episode details how Claude, an AI model, planned the rover’s route, using orbital and ground images to avoid hazards. Watch the AI’s route planning in action, contrasted with the actual drive.

Go to video at:

https://www.youtube.com/watch?v=wubO9j1keNA

Also, go to this Jet Propulsion Laboratory release Perseverance’s use of AI at:

https://www.jpl.nasa.gov/news/nasas-perseverance-rover-completes-first-ai-planned-drive-on-mars/

Image credit: SpaceX/Inside Outer Space screengrab

SpaceX has announced a Space Situational Awareness system called Stargaze.

The space-based Stargaze system uses data collected from nearly 30,000 in orbit star trackers mounted on Starlink satellites.

The safety and sustainability of satellite operations in low Earth orbit (LEO) will benefit by Stargaze operations, the company explains, and its screening data will be made available to the broader satellite operator community free of charge in the coming weeks.

Image of spent rocket body.
Image credit: Astroscale-Japan

 

 

 

 

 

 

Large uncertainties

“Practices—such as leaving rocket bodies in LEO, operators maneuvering their satellites without sharing trajectory predictions or coordinating with other active satellites, and countries conducting anti-satellite tests—have heightened the risk of collision, necessitating improvements in space-traffic coordination,” explains SpaceX.

“Conventional methods typically observe objects only a limited number of times per day, causing large uncertainties in orbital predictions, further compounded by volatile space weather.”

Image credit: SpaceX/Inside Outer Space screengrab

Conjunction Data Messages

The Stargaze system offers an increase in detection capability compared to conventional ground-based systems, SpaceX reports.

Stargaze can autonomously detect orbiting objects, aggregating this information to generate orbit estimates and predictions of position and velocity for all detected objects in near real-time.

These predictions are integrated into a space traffic management platform that identifies potential close approaches between objects in space and generates Conjunction Data Messages or (CDMs)

Things are messy in the heavens.
Image credit: The Aerospace Corporation/CORDS

 

 

 

 

 

Management platform

“To fully realize the utility of such frequent observations, SpaceX developed this system to provide conjunction screening results within minutes, compared to the current industry standard of several hours,” the company explains.

SpaceX will be making Stargaze conjunction data available to all satellite operators, free of charge, via a space-traffic management platform.

Close-call

Citing its own issues with close-calls, SpaceX said that late last year, a Starlink satellite encountered a conjunction with a third-party satellite that was performing maneuvers, but whose operator was not sharing ephemeris. 

Until five hours before the conjunction, the close approach was anticipated to be roughly five and a half miles (9,000 meters).

That was considered a safe miss-distance with zero probability of collision. 

Credit: SpaceX/Starlink

 

 

 

 

 

 

However, with just five hours to go, the third-party satellite performed a maneuver which changed its trajectory and collapsed the anticipated miss distance to roughly 200 feet (60 meters).

“Ultimately, the Starlink satellite was able to react within an hour of the maneuver being detected, planning an avoidance maneuver to reduce collision risk back down to zero,” SpaceX said.

By providing this ephemeris sharing and conjunction screening service free of charge, the company states, “we hope to motivate operators to take similar steps towards ephemeris sharing and safe flight.”

For more information on Stargaze, go to this posting on the SpaceX Starlink website at:

https://starlink.com/updates/stargaze

A schematic diagram showing the planned location of the Sun-Earth L5 point for the “Xihe-2” spacecraft.
Image credit: Nanjing University

China has announced its intention to send its Xihe-2 probe to the Sun-Earth L5 point between 2028 and 2029.

Xihe-2 would carry out three-dimensional observations of the sun from entirely new wavelengths and perspectives, explains Fang Cheng of the School of Astronomy and Space Science at Nanjing University.

The probe would maintain orbital stability without consuming excessive energy, and is being designed to have a lifespan as long as 7 years.

Forecasting duties

From its Sun-Earth L5 position, Xihe-2 would observe solar active regions and perform forecasting duties, eyeing harmful space weather such as solar flares and coronal mass ejections. The spacecraft would provide more preparation time for any responses here on Earth.

Earth’s Sun can toss out powerful solar storms that can impact infrastructure on Earth’s surface, in near-Earth orbit, including astronaut travel to and from the Moon and Mars.
Image credit: NASA’s Solar Dynamics Observatory, or SDO – NASA’s Living With a Star Program

“To date, humans have launched more than 70 solar probes, the vast majority of which are located along the Sun-Earth line, a few orbit the Sun, and no probe has yet stayed at the Sun-Earth L5 point. Therefore, ‘Xihe-2’ will provide humans with a completely new ‘observer’ perspective for studying the Sun,” said Li Chuan, chief designer of the Xihe spacecraft’s scientific and application system and professor at the School of Astronomy and Space Science of Nanjing University

Space-based solar exploration

Xihe-1 was lofted into Earth orbit in October 2021, China’s first solar exploration scientific and technological experimental satellite. That spacecraft opened the era of China’s space-based solar exploration.

According to the Xinhua News Agency, Xihe is the mother of the sun in the Classic of Mountains and Seas, the goddess who controls the rising and setting of the sun in the Chu Ci, and also an official title in ancient China for observing celestial phenomena and formulating calendars.

Image credit: NASA

NASA appears to be continuing its re-contacting efforts with the MAVEN (Mars Atmosphere and Volatile EvolutioN). The agency’s Deep Space Network (DSN) is continuing recovery activities after losing contact with the Mars orbiter on December 6.

A posting last month noted that, although no spacecraft telemetry has been received since Dec. 4, a brief fragment of tracking data was received on Dec. 6 as part of an ongoing radio science campaign.

“Analysis of that signal suggests that the MAVEN spacecraft was rotating in an unexpected manner when it emerged from behind Mars. Further, the frequency of the tracking signal suggests MAVEN’s orbit trajectory may have changed. The team continues to analyze tracking data to understand the most likely scenarios leading to the loss of signal.”

Image credit: NASA/JPL-Caltech

In a January 26 posting, NASA said that, as spacecraft and rovers at Mars emerged from solar conjunction – a period when the Red Planet and Earth are on opposite sides of the Sun and contact with Mars missions isn’t possible – efforts were resumed to re-contact MAVEN.

Deep space station

Today, as viewed on the Jet Propulsion Laboratory’s Deep Space Network Now website, the Goldstone Deep Space Station (DSS 24) is in use and is targeting MAVEN.

No official word as yet if MAVEN is responding.

Go to the Deep Space Network Now website at:

https://eyes.nasa.gov/apps/dsn-now/dsn.html

Image credit: NASA/JPL-Caltech

Image credit: ESA

The European Space Agency has green-lighted a very complex reentry of a specially designed spacecraft. They are building a sensor-loaded satellite specifically built to dive into the Earth’s atmosphere.

As a headfirst, artificial “fall guy” shooting through first thin and then thicker air, it would collect data on how materials react and introduce pollutants into the upper stratosphere.

In other words, it’s an atmospheric stab for science.

Image credit: ESA

 

 

“Understanding how different materials behave as they burn up could help engineers design satellites that fully disintegrate, leaving nothing behind in orbit or in the atmosphere.”

For more details, go to my new Space.com story – “What actually happens to a spacecraft during its fiery last moments? Here’s why ESA wants to find out” – at:

https://www.space.com/space-exploration/satellites/what-actually-happens-to-a-spacecraft-during-its-fiery-last-moments-heres-why-esa-wants-to-find-out

Image credit: Amazon Leo

The Amazon low Earth orbit (LEO) constellation — formerly named Project Kuiper – is a worrisome initiative, particularly for astronomers, given that 3,232 satellites are planned to orbit the Earth.

The state-of-the-art satellite technology is to deliver reliable, high-speed connectivity.

The Amazon mega-constellation will potentially impact astronomical research and aesthetic appreciation of the night sky, according to a new research paper led by Anthony Mallama of the International Astronomical Union’s (IAU) Center for the Protection of the Dark and Quiet Sky.

Image credit: Amazon Leo

Reflected sunlight

Satellite attitude determines how sunlight is reflected and influences brightness.

The new research paper focuses on Amazon low Earth orbit satellites at roughly 390 miles (630 kilometers) altitude.

Mallama and colleagues note that future Amazon spacecraft are expected to orbit at lower altitudes and therefore will be brighter.

Image credit: Amazon Leo

Ground-based observatories

Amazon Leo, the paper adds, has recently stated that it is deploying ground-based observatories to measure reflectivity brightness. The intent of doing so is to improve performance through block upgrades.

“The mean apparent magnitude of all Amazon Leo satellites is 6.28 based on 1,938 observations. For spacecraft in their operational mode, 92% exceeded the IAU brightness limit for interference with research, while 25% distract from aesthetic appreciation of the night sky,” the paper explains.

What’s the SCORE?

Meanwhile, a Satellite Constellation Observation Repository (SCORE) has been developed and maintained by the IAU Center for the Protection of the Dark and Quiet Sky.

SCORE serves as a centralized repository for satellite brightness observations. Its primary function is to provide a comprehensive and organized platform for researchers to contribute, store, and access observational data of artificial space objects.

To access the research paper – “Brightness Characterization and Modeling for Amazon Leo Satellites” – go to:

https://arxiv.org/pdf/2601.07708

Artwork depicts Cluster satellite reentry.
Image credit: ESA/David Ducross

Reentering space clutter and its influence on Earth’s stratosphere continues to draw research attention.

“We’re really changing the composition of the stratosphere into a state that we’ve never seen before,” said John Dykema, an applied physicist at Harvard’s School of Engineering and Applied Sciences (SEAS), who warns that scientists today poorly understand many of the impacts.

Dykema is focused on research at the intersection of atmospheric chemistry and atmospheric radiation.

Image credit: Salata Institute; Source: Jonathan’s Space Report; image created with Datawrapper

Active satellites

There were 14,300 active satellites orbiting at the start of January.

Of active units today, over 9,200 belong to SpaceX, which in December filed a request with the Federal Communications Commission to launch another 15,000.

Amazon has plans for more than 3,000, while Amazon founder Jeff Bezos’s Blue Origin this month announced plans for a network of 5,408 more.

Similarly, China has also begun launching mega-constellations of spacecraft.

Dykema notes the fact that, because these satellites are relatively inexpensive and the technology is rapidly improving, many are scuttled after just five or 10 years: directed to reenter the atmosphere so they don’t litter space real estate above Earth.

Launch and reentry particle emissions in the Earth’s stratosphere.
Image credit: The Aerospace Corporation

Action/reaction

That reentry action means they release a mix of heavy metal and carbon particles that float down closer to Earth, into the otherwise chemically stable stratosphere and where ozone screens our planet.

What is becoming apparent, Dykema said in a January 27 Harvard Climate Blog posting, is that satellite reentry risks disrupting the global climate system and further depleting the ozone layer, which shields all living things from DNA-destroying ultraviolet radiation.

The high-speed of reentry ignites a satellite, organic materials onboard – such as plastics or carbon-fiber composites – releasing particles of black carbon, the same fine soot in wood or coal smoke.

Image credit: NOAA

Structural and chemical differences

Black carbon comes in different forms. Some particles follow repeating patterns and are “crystalline,” like graphite, Dykema reports. Others are random, or “amorphous.”

Those structural and chemical differences – including how the carbon atoms bond with elements like hydrogen – determine how the black carbon affects incoming sunlight.

Some particles scatter sunlight; some absorb it. Some absorb infrared light, but not ultraviolet.

Thermal energy

Dykema adds that how this process plays out in the stratosphere, and the impact on the climate, remains uncertain.

“We’re putting thermal energy into the Earth’s climate system, but we’re putting it in new places,” Dykema said. “We don’t really understand the implications of changing stratospheric circulation. It could cause storm tracks to move. Maybe it could shift climate zones, or possibly be a new source of droughts and floods.”

The key question: what happens as humanity puts more and more material into orbit, much of it eventually returning as debris? If aluminum oxide continues to accumulate, ozone loss could become more serious.

Taking the fall. Space hardware dives into Earth’s atmosphere with some fragments making their way to the ground.
Image credit: ESA/D.Ducros

“It’s not the most efficient way to create an ozone hole, but it does cause additional ozone erosion, which slows the recovery,” said Dykema.

What should policymakers do?

Dykema suspects that changes to stratospheric circulation may ultimately prove more consequential than the additional ozone loss, because the outcomes are so uncertain and potentially far-reaching.

For the moment, many questions “are not really amenable to straightforward, linear analysis,” Dykema said, cautioning that “the ozone loss is significant, and we’re putting so much stuff up there that it could grow in ways that are not proportional.”

Governments and regulators could push for a more sustainable use of space, from the materials used in satellite construction to the types of propellants powering rockets.

Solid fuels, for example, produce aluminum and aluminum oxide in exhaust, suggesting that decisions about solid versus liquid propellant, and about which regions and seasons to launch in, could have real atmospheric consequences.

The question, Dykema suggests, as the satellite launch rate accelerates, is whether policymakers will act on those concerns before the invisible wake of our spacefaring ambitions becomes impossible to ignore?

Read the entire blog here:

Burning satellites in the stratosphere: Emerging questions for climate  

A team of astronomers have used a new AI-assisted method to search for rare astronomical objects in the Hubble Legacy Archive.

The team sifted through nearly 100 million image cutouts in just two and a half days, uncovering nearly 1400 anomalous objects, more than 800 of which had never been documented before.


Image credit: ESA/Hubble & NASA, D. O’Ryan, P. Gómez (European Space Agency), M. Zamani (ESA/Hubble)

Go to this research paper — “Identifying astrophysical anomalies in 99.6 million source cutouts from the Hubble legacy archive using AnomalyMatch” — at:

https://www.aanda.org/articles/aa/full_html/2025/12/aa55512-25/aa55512-25.html