Space & Physics

In search for red aurorae in ancient Japan

Ryuho Kataoka, a Japanese auroral scientist, played a seminal role in searching for evidence of super-geomagnetic storms in the past using historical methods

Published

3 years ago

February 5, 2024

Karthik Vinod

Professor Ryuho Kataoka in his office at NIPR, with the fan-shaped painting behind him, Picture courtesy: RK Works

Aurorae seen on Earth are the end of a complex process that begins with a violent, dynamic process deep within the sun’s interior.

However, studying the depths of the sun is no easy task, even for scientists. The best they can do is to observe the surface using space-based telescopes. One problem that scientists are attempting to solve is how a super-geomagnetic storm on Earth comes to being. These geomagnetic storms find their roots in sunspots, that are acne-like depressions on the sun’s surface. As the sun approaches the peak of its 11-year solar cycle, these sunspots, numbering in the hundreds, occasionally release all that stored magnetic energy into deep space, in the form of coronal mass ejections (CMEs) (which are hot wisps of gas superheated to thousands of degrees).

If the earth lies in the path of an oncoming CME, the energy release from their resultant magnetic field alignment can cause intense geomagnetic storms and aurorae on Earth.

This phenomenon, which is astrophysical and also electromagnetic in nature, can have serious repercussions for our modern technological society.

Super-geomagnetic storms, a particularly worse form of geomagnetic storm, can induce power surges in our infrastructure, causing power outages that can plunge the world into darkness, and can cause irreversible damages to our infrastructure. The last recorded super-geomagnetic storm event occurred more than 150 years ago. Known as the Carrington event, the storm destroyed telegraph lines across North America and Europe in 1859. The risk for a Carrington-class event to happen again was estimated to be 1 in 500-years, which is quite low, but based on limited data. Ramifications are extremely dangerous if it were to ever happen.

However, in the past decade, it was learnt that such super-geomagnetic storms are much more common than scientists had figured. To top it all, it wasn’t just science, but it was a valuable contribution by art – specifically ancient Japanese and Chinese historical records that shaped our modern understanding of super-geomagnetic storms.

Ryuho Kataoka, a Japanese space physicist, played a seminal role in searching for evidence of super-geomagnetic storms in the past using historical methods. He is presently an associate professor in physics, holding positions at Japan’s National Institute of Polar Research, and The Graduate University for Advanced Studies.

“There is no modern digital dataset to identify extreme space weather events, particularly super-geomagnetic storms,” said Professor Kataoka. “If you have good enough data, we can input them into supercomputers to do physics-based simulation.”

However, sunspot records go until the late 18th century when sunspots were actively being cataloged. In an effort to fill the data gap, Professor Kataoka decided to be at the helm of a very new but promising interdisciplinary field combining the arts with space physics. “The data is limited by at least 50 years,” said Professor Kataoka. “So we decided to search for these red vapor events in Japanese history, and see the occurrence patterns … and if we are lucky enough, we can see detailed features in these lights, pictures or drawings.” Until the summer of 2015, Ryuho Kataoka wasn’t aware of how vast ancient Japanese and Chinese history records really were.

“There is no modern digital dataset to identify extreme space weather events, particularly super-geomagnetic storms,” said Professor Kataoka.

In the past 7 years, he’s researched a very specific red aurora, in documents extending to more than 1400 years. “Usually, auroras are known for their green colors – but during the geomagnetic storm, the situation is very different,” he said. “Red is of course unusual, but we can only see red during a powerful geomagnetic storm, especially in lower latitudes. From a scientific perspective, it’s a very reasonable way to search for red signs in historical documents.”

A vast part of these historical red aurora studies that Professor Kataoka researched came from literature explored in the last decade by the AURORA-4D collaboration. “The project title included “4D”, because we wanted to access records dating back 400 years back during the Edo period,” said Professor Kataoka.

“From the paintings, we can identify the latitude of the aurora, and calculate the magnitude or amplitude of the geomagnetic storm.” Clearly, paintings in the Edo period influenced Professor Kataoka’s line of research, for a copy of the fan-shaped red aurora painting from the manuscript Seikai (which translates to ‘stars’) hangs on the window behind his office desk at the National Institute of Polar Research.

The painting fascinated Professor Kataoka, since it depicted an aurora that originated during a super-geomagnetic storm over Kyoto in 1770. However, the painting did surprise him at first, since he wondered whether the radial patterns in the painting were real, or a mere artistic touch to make it look fierier. “That painting was special because this was the most detailed painting preserved in Japan,” remarked Professor Kataoka. “I took two years to study this, thinking this appearance was silly as an aurorae scientist. But when I calculated the field pattern from Kyoto towards the North, it was actually correct!”

Fan-shaped red aurora painting from the ‘Seikai’, dated 17th September, 1770; Picture Courtesy: Matsusaka City, Mie Prefecture.

The possibility to examine and verify historical accounts using science is also a useful incentive for scholars of Japanese literature and scientists partaking in the research.

“This is important because, if we scientists look at the real National Treasure with our eyes, we really know these sightings recorded were real,” said Professor Kataoka. “The internet is really bad for a survey because it can easily be very fake,” he said laughing. It’s not just the nature in which science was used to examine art – to examine Japanese “national treasures” that is undoubtedly appealing, but historical accounts themselves have contributed to scientific research directly.

“From our studies, we can say that the Carrington class events are more frequent than we previously expected,” said Professor Kataoka. There was a sense of pride in him as he said this. “This Carrington event is not a 1 in 200-year event, but as frequent as 1 in 100 years.” Given how electricity is the lifeblood of the 21st century, these heightened odds do ingrain a rather dystopian society in the future, that is ravaged by a super-geomagnetic storm.

Professor Kataoka’s work has found attention within the space physics community. Jonathon Eastwood, Professor of Physics at Imperial College London said to EdPublica, “The idea to use historical information and art like this is very inventive because these events are so rare and so don’t exist as information in the standard scientific record.”

There’s no physical harm from a geomagnetic storm, but the threat to global power supply and electronics is being increasingly recognized by world governments. The UK, for instance, identified “space weather” as a natural hazard in its 2011 National Risk Register. In the years that followed, the government set up a space weather division in the Met Office, the UK’s foremost weather forecasting authority, to monitor and track occurrences of these coronal mass ejections. However, these forecasts, which often supplement American predictions – namely the National Oceanic and Atmospheric Administration (NOAA) – have failed to specify previously where a magnetic storm could brew on Earth, or predict whether a coronal mass ejection would ever actually strike the Earth.

The former occurred during the evacuation process for Hurricane Irma in 2017, when amateur radio ham operators experienced the effects of a radio blackout when a magnetic storm affected the communications network across the Caribbean. The latter occurred on another occasion when a rocket launch for SpaceX’s Starlink communication satellites was disrupted by a mild geomagnetic storm, costing SpaceX a loss of over $40 million.

Professor Kataoka said he wishes space physicists from other countries participate in similar interdisciplinary collaborations to explore their native culture’s historical records for red aurora sightings. He said the greatest limitation of the AURORA-4D collaboration was the lack of historical records from other parts of the world. China apparently boasts a history of aurora records longer than Japan, with a history lasting before Christ himself. “Being Japanese, I’m not familiar with British, Finnish or Vietnamese cultures,” said Professor Kataoka. “But every country has literature researchers and scientists who can easily collaborate and perform interdisciplinary research.” And by doing so, it’s not just science which benefits from it, but so is ancient art whose beauty and relevance gains longevity.

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Karthik Vinod

Karthik Vinod is a freelance science writer and journalist from Kochi, India.

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Space & Physics

Meteorite Dust Reveals Evidence of Magnetic Field in the Young Solar System

A magnetic field in the early solar system has been detected in ancient meteorite grains, offering evidence that magnetism helped shape the young sun.

Published

19 hours ago

August 25, 2026

EP Staff

A magnetic field in the early solar system

Ancient grains in an Antarctic meteorite reveal evidence of a magnetic field in early solar system, suggesting magnetism helped shape the young sun

Tiny mineral grains preserved inside an ancient meteorite have recorded evidence of a magnetic field that existed during the earliest stages of the solar system, suggesting that magnetism, alongside gravity, helped shape the young sun and its surrounding disk of gas and dust.

Ancient Meteorite Records Reveal a Magnetic Field in the Early Solar System

Scientists at the Massachusetts Institute of Technology (MIT) examined microscopic grains in a meteorite recovered from Antarctica and found traces of ancient magnetism dating to the first 200,000 years of solar system history. The findings provide what researchers describe as the earliest known evidence of a magnetic field in the infant solar system.

The study, published in the Proceedings of the National Academy of Sciences, challenges the view that gravity alone drove the transformation of the early solar system from a cloud of gas and dust into a flattened disk that eventually produced the sun and planets.

“This transition, from a spherical cloud to a protoplanetary disk, is one of the most significant events in all of solar system history,” said Benjamin Weiss, professor of Earth and Planetary Sciences at MIT, in a statement issued. Measurements from the study, he said, indicate that magnetism likely played a role.

Magnetic records preserved in meteorite grains

The researchers studied DOM 08006, a primitive meteorite discovered in 2008 in the Dominion Range of Antarctica. The meteorite contains calcium-aluminum-rich inclusions, or CAIs, which formed during the earliest period of solar system development.

CAIs are among the oldest known solid materials from the solar system. Some of the grains contain magnetic minerals that can preserve the imprint of a magnetic field present when they formed.

The team isolated tiny grains from the meteorite and subjected them to a series of tests to determine whether they retained remanent magnetisation — a lasting record of an earlier magnetic field.

The researchers found evidence of a magnetic field with an estimated strength of about 150 to 600 microteslas. That is roughly three to 12 times stronger than Earth’s magnetic field today.

The preservation of these records was possible because DOM 08006 appears to have undergone relatively little alteration during its long history.

“Other meteorites went through many different processes over this 4.5 billion year history,” Weiss said. “But somehow, DOM has experienced less alteration than any other meteorite.”

Magnetism before the planets

Scientists already had evidence of magnetic fields in the solar system several million years after its formation, when the sun had formed and the planets were beginning to take shape.

The new measurements push that evidence much further back — to a period when the solar system was still a collapsing cloud of gas and dust and the sun itself was beginning to form.

In the early solar system, electrically charged particles moving through the developing disk could have generated a magnetic field. That field may then have influenced the movement of gas and material towards the central star.

The researchers argue that magnetism therefore needs to be considered alongside gravity when reconstructing how the early solar system evolved.

“We think these kinds of magnetic fields were helping to move gas from the protoplanetary disk, in toward this central star, the sun,” said Cauê Borlina, the study’s first author and now an assistant professor at Purdue University.

The findings do not replace gravity as the main force shaping the early solar system. Instead, they suggest that magnetic fields were another important part of the physical processes that brought material together and helped the young sun grow.

The study was led by Borlina, with Weiss, Elias Mansbach and Nilanjan Chatterjee of MIT, along with researchers from Tsinghua University, the University of Cambridge, Caltech and the University of California, Los Angeles

Space & Physics

NASA Puts $500,000 Prize on Better Satellite Tracking

NASA is offering up to 500,000 dollars to develop affordable technology that can improve satellite tracking by measuring atmospheric drag in low Earth orbit. The effort aims to help operators predict orbital changes more accurately as solar activity alters the thin upper atmosphere.

Published

4 days ago

August 22, 2026

EP Staff

NASA-linked deep-space communications antenna used to track spacecraft and support satellite operations

A radio antenna at the INTA-NASA Madrid Deep Space Communications Complex, part of the ground infrastructure used to communicate with and track spacecraft. Representational image. Image credit: Alejandro De Roa/Pexels

A faint layer of air high above Earth is becoming an important concern for satellite tracking operators. NASA is now offering up to USD 500,000 to individual winning teams that can develop a practical way to monitor it. The US space agency opened the Orbital Clarity Challenge on August 19, asking researchers and companies to develop instruments that can determine how much drag spacecraft experience in low Earth orbit. Up to four teams can win the top prize, taking the potential total award to USD 2 million.

The focus is the thermosphere, a region that begins about 80 kilometres above Earth and extends hundreds of kilometres into space. The air here is extremely sparse, but spacecraft moving through it still encounter enough resistance to gradually alter their orbits.

Untitled design 2026 08 22T110535.497 — The Sun rises over Earth’s horizon, highlighting the upper atmosphere, including the thermosphere, where solar activity can increase atmospheric drag on satellites in low Earth orbit. Representational image. Image credit: Zelch Csaba/Pexels

That resistance does not remain constant. When the Sun becomes more active, bursts of energy can heat the upper atmosphere. The thermosphere expands, increasing the amount of gas encountered by satellites. The resulting increase in drag can change their altitude and make their future position harder to calculate. For spacecraft operators, even a small difference can matter when several objects are moving through the same orbital region.

A Gap in the Data

NASA already relies on computer models to estimate atmospheric drag. But those calculations depend on how well scientists understand conditions in the upper atmosphere at a particular time and location. The agency wants new technology that can provide more direct information.

Under the competition, proposed instruments should be inexpensive enough to be deployed widely. NASA says they could potentially be carried aboard commercial spacecraft as hosted payloads, allowing measurements to be collected from several points in orbit rather than from a limited number of dedicated missions.

The competition will run through several stages, with NASA aiming to move successful ideas from an initial concept towards an instrument that can eventually be tested in space. Winning teams are also expected to receive an opportunity for an orbital demonstration. Applications for the first stage close in November 2026.

Satellite Tracking: Why this Matters?

The number of spacecraft operating in low Earth orbit has grown rapidly, with satellites supporting communications, navigation, Earth observation and scientific research.

Their paths are affected by several forces, including the thin atmosphere at orbital altitude. During periods of strong solar activity, atmospheric drag can rise sharply and contribute to changes in orbital altitude. Better information about those changes could help operators plan manoeuvres more accurately and improve forecasts of when satellites will descend from orbit.

NASA’s prize is therefore aimed at a relatively small piece of the space infrastructure puzzle: getting a clearer picture of the air that satellites are still moving through, even hundreds of kilometres above the ground.

Space & Physics

Sophie Adenot Makes History as First Frenchwoman to Walk in Space

French astronaut Sophie Adenot has become the first Frenchwoman to perform a spacewalk, spending 6 hours 23 minutes outside the International Space Station.

Published

7 days ago

August 19, 2026

Sebin Pious

Image credit/ ESA - A. Conigli

French astronaut Sophie Adenot has become the first Frenchwoman to perform a spacewalk, spending 6 hours and 23 minutes outside the International Space Station to begin repairs to its exterior communications system.

French astronaut Sophie Adenot made European space history on Tuesday by becoming the first French woman to perform a spacewalk outside the International Space Station. Adenot, 44, stepped outside the orbiting laboratory alongside American astronaut Anil Menon, floating roughly 400 kilometres above the Earth for 6 hours and 23 minutes to begin a repair of the station’s exterior communications equipment.

“I’m out,” Adenot said as she exited the station. “I feel very good now.”

A Repair Job That Ran Long The astronauts’ task was to replace an aging space-to-ground antenna on the station’s Z1 truss — the primary link carrying high-speed data, voice calls and video between the station and mission control in Houston. The antenna had stopped tracking NASA’s data relay satellites since November and had been out of service since, with a second antenna carrying the station’s communications load in the meantime.

Menon and Adenot successfully removed the failed antenna and secured it to the truss structure, but disconnecting its electrical cables and loosening its mounting bolts took longer than planned, leaving no time to install the replacement unit. NASA has scheduled a second spacewalk for Tuesday, August 25, to complete the installation. The station’s communications were not affected by the delay, as the backup antenna continued operating throughout.

Inside the station, astronauts Jack Hathaway and Jessica Meir coordinated the operation from the control desk, operating the station’s robotic arm and monitoring the spacewalkers’ life support systems throughout.

Days of Preparation Before the Hatch Opened Spacewalks demand days of preparation before the airlock ever opens. In the lead-up, Adenot and Menon spent dozens of hours readying their gear inside the station — inspecting safety tethers, organising tools, servicing backup emergency jetpacks, charging suit batteries, checking for pressure leaks, and testing biomedical sensors and radios.

Spacewalk complete. ✅

After 6 hours and 23 minutes outside the International Space Station, @Soph_astro is safely back inside.

With today’s EVA, Sophie becomes the first French woman to perform a spacewalk. 🇫🇷 pic.twitter.com/i3BghrdaRK— European Space Agency (@esa) August 18, 2026

“A successful [spacewalk] starts long before the hatch opens, and that’s where my focus has been these past few days: rehearsing, preparing and focusing,” Adenot said on social media before the excursion.

Suit fitting was a major focus of the preparation: working inside a heavy, pressurised spacesuit for over six hours puts considerable strain on an astronaut’s hands and shoulders, and engineers on the ground worked closely with Adenot to customise her suit and reduce pressure points.

A Milestone for European Space Exploration Adenot brought extensive technical experience to the mission. A trained engineer and former helicopter test pilot, she was selected for astronaut training by the European Space Agency in 2022 and launched to the space station in February 2026, becoming only the second French woman in history to reach space, after physician-astronaut Claudie Haigneré in 1996. With Tuesday’s spacewalk, she also became the second European woman ever to conduct a spacewalk, after Italian astronaut Samantha Cristoforetti in 2022, and the fifth French citizen overall to do so. The last French citizen to walk in space was Thomas Pesquet.

Despite the milestone, Adenot credited the wider team behind the mission. “My deepest gratitude goes to everyone who made this possible — pioneers who came before us, but also the incredible teams working behind the scenes today,” she said after returning inside the station.