TYB
NASA Astronomy Picture of the Day
June 3, 2026
Andromeda Through Gas and Dust
Over 1000 years ago, Persian astronomer Abd al-Rahman al-Sufi published humanity’s oldest known record of the Andromeda Galaxy in "The Book of Fixed Stars" (Bodleian Library MS. Marsh 144 p. 167). 800 years later, Andromeda became the 31st entry in Charles Messier’s "Catalogue of Nebulae and Star Clusters". From “a small cloud” to “nebula” and now known to be our nearest major galaxy, Andromeda has remained a fundamental astronomical object. Today’s image, taken over 202 hours, shows how far we have come in our ability to observe our neighbor. The diffuse red and blue clouds are mostly foreground ionized hydrogen and oxygen well within our Milky Way. Pink-red clouds of hydrogen ionized by the energetic light of young stars trace the galaxy’s dusty spiral arms. M32 and M110 are satellite galaxies pictured orbiting the larger Andromeda. Despite its long history of observation through ancient unaided eyes to modern telescopes, Andromeda still holds countless secrets that astronomers will continue to search for, including how galaxies merge and evolve, as well as the nature of the dark matter that galaxies reside in.
https://apod.nasa.gov/apod/astropix.html
https://www.youtube.com/watch?v=iSuBCBI6COg
Solar Flares and CMEs at Earth - More Likely | S0 News and frens
June.3.2026
https://www.youtube.com/watch?v=Tk45_Un_1bs
https://www.youtube.com/watch?v=E7nS-G3MQvk (NOAA SWPC Video Update 2 June 2026)
https://www.youtube.com/watch?v=GdXPauhRoQI (Solar Ham: M7.7, + X1.0 Solar Flares and CMEs (6/3/2026))
https://www.youtube.com/watch?v=pfUpP4dJMIw (Stefan Burns: A Mega Solar Storm is Coming… (Emergency Update))
https://www.youtube.com/watch?v=RwUlaP1X9Mc (Chuck's Astro: LIVE Sun: Giant Sunspot)
https://www.youtube.com/watch?v=d68dPHy9bCo (On the Pulse With Silki: MOST Dangerous Volcano near Mexico City started INTENSE ERUPTION - FIFA OPENING Ceremony AT RISK ?)
https://www.youtube.com/watch?v=cojF7x52f_E (EarthMaster: New Large Earthquake 5.2 Hawaii. Did anyone feel this? Tuesday Night)
solar activity
https://science.nasa.gov/blogs/solar-cycle-25/2026/06/03/strong-flare-erupts-from-sun-10/
https://watchers.news/2026/06/03/m9-3-m7-7-solar-flares-erupt-ar-4455-earth-directed-cmes-june-3-2026/
https://watchers.news/2026/06/03/x1-0-solar-flare-geoeffective-region-4455-june-3-2026/
https://www.swpc.noaa.gov/news/r2-conditions-reached-03-june
https://www.spaceweather.gov/news/r1-conditions-return-lower-level-m-class-flares
https://www.nesdis.noaa.gov/our-environment/space-weather/the-effects-of-space-weather-earth
everything else
https://www.newsweek.com/map-shows-2-earthquakes-over-5-0-magnitude-strike-california-coast-12026860
https://en.tempo.co/read/2106580/mount-semeru-hit-by-583-eruptive-earthquake-in-late-may
https://watchers.news/2026/06/03/severe-thunderstorms-and-flooding-threat-forecast-across-the-plains-through-thursday/
https://watchers.news/2026/06/03/severe-tropical-storm-jangmi-leaves-23-injured-60-000-without-power-after-landfall-in-wakayama-japan/
https://portageonline.com/articles/three-tornadoes-confirmed-as-severe-storms-sweep-across-manitoba
https://www.ansa.it/english/news/general_news/2026/06/03/tornado-fells-trees-in-rome_51fb88e3-26c2-4075-b142-771c9f342e2a.html
https://meteoagent.com/schumann-resonance-forecast
https://earthquake.usgs.gov/earthquakes/map/
https://www.volcanodiscovery.com/earthquakes-volcanoes/news/304019/Volcano-earthquake-report-for-Wednesday-3-Jun-2026.html
https://www.tornadohq.com/
https://www.swpc.noaa.gov/
https://spaceweather.com/archive.php?view=1&day=03&month=06&year=2026
https://avi-loeb.medium.com/discovery-of-a-polar-interstellar-meteor-polar-im-from-april-1-2026-0fbc0726059b
ICYMI space objects
https://www.foxweather.com/earth-space/midwest-meteor-streaks-michigan-ohio-region
https://patch.com/rhode-island/across-ri/fireball-streaking-over-rhode-island-was-elephant-sized-meteor-nasa-says
Discovery of a Polar Interstellar Meteor (Polar-IM) from April 1, 2026
June 3, 2026
Following the rare meteor explosion over Boston at 2:06PM Eastern Time on May 30, 2026, I checked the database of NASA’s Center for Near-Earth Object Studies (CNEOS) (accessible here), which reports global bolide detections from U.S. Government sensors.
Apparently, the Boston fireball released about 7% of the Hiroshima atomic bomb energy, equivalent to 1.1 kilotons of TNT. The bolide with a diameter of 1.6 meter — corresponding to a mass of order 6 metric tons - was traveling at a speed of a hundred times the speed of sound.
Massive impactors of this scale occur once every couple of months over the entire Earth. The relic fragments from the meteoroid likely landed in Cape Cod Bay.
While looking at the CNEOS database, I noticed a recent meteor from 02:13:14 UTC on April 1, 2026, with a large polar velocity component relative to Earth of 59.8 kilometers per second, well above the local escape speed from the Solar System of 42.14 kilometers per second.
Since the Earth’s poles are tilted by only 23.4 degrees relative to the orbital plane of the Earth around the Sun, the high polar speed of this meteor should not be corrected by much as a result of the motion of the Earth around the Sun, when transforming to the Sun’s frame.
This led me to immediately conclude that the object is probably not bound by gravity to the Solar System and is interstellar in origin.
My inference was quickly confirmed by my brilliant postdoc Richard Cloete who already had the analysis formalism available from a previous paper that we wrote on interstellar meteors.
Within a couple of days, Richard and I completed a new paper (available here), in which we identify this polar interstellar meteor, labeled Polar-IM, as the most robust interstellar meteor candidate ever reported in the CNEOS fireball database.
The fireball of Polar-IM was detected at latitude −41.9◦, longitude −54.7◦, and altitude 90.5 kilometers over the South Atlantic Ocean, east of Argentina.
We transformed its reported Earth-fixed velocity vector (+3.6, −34.6, +59.8) kilometers per second to an inertial geocentric state, accounted for Earth’s gravitational acceleration with a two-body hyperbolic model, added the JPL Horizons heliocentric velocity of Earth, and tested the resulting heliocentric orbit against the solar escape speed. The final velocity component in the polar direction of +47.09 kilometers per second exceeded by itself the local solar escape speed.
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The full heliocentric speed of 51.73 kilometers per second, corresponding to a heliocentric excess speed of 30.00 kilometers per second, and an inclination angle of 89.4 degrees.
We propagated measurement uncertainty through a million Monte-Carlo realizations using the empirical post-2018 low-discrepancy CNEOS error model (reported in a 2025 paper, accessible here).
No realization yielded a bound heliocentric orbit, giving a statistical confidence on the interstellar origin of Polar-IM of more than 99.9997%. The Monte-Carlo statistical confidence corresponds to a 12.82-σ margin-to-scatter ratio under the adopted error model.
The telescopic discoveries of the interstellar objects 1I/`Oumuamua, 2I/Borisov, and 3I/ATLAS, demonstrated that large interstellar objects transit the inner Solar System.
Population models predict many more meter-scale interstellar objects entering at rates potentially detectable with existing monitoring networks.
Although these small bodies evade telescopic detection, they can reveal themselves as fireballs when they enter Earth’s atmosphere and generate a fireball as a result of their friction on air.
The inferred velocity of Polar-IM is very reasonable for an interstellar origin.
Polar IM is the most robust interstellar meteor in the CNEOS catalog so far, as our analysis identifies its interstellar origin with a statistical confidence of over 99.9997%.
The reported Polar-IM coordinates place the event over the South Atlantic Ocean, east of Argentina. The impact energy is modest, only 0.086 kiloton TNT equivalent, and the reported altitude is high, 90.5 kilometers.
These two facts make material recovery less straightforward than in the impact site of a larger, lower-altitude bolide such as the 2014 interstellar meteor, IM1, where I led an ocean expedition in June 2023 that resulted in chemical analysis of recovered molten fragments (as reported here). The Polar-IM event may have fragmented high in the atmosphere, and any surviving material would require a fall-ellipse calculation before the feasibility of a search could be assessed.
Given its impact energy and speed, Polar-IM had a mass of about 150 kilograms and a diameter of roughly half a meter.
The first follow-up priority is therefore a higher-fidelity reconstruction rather than an expedition, with a goal to: (1) produce targeted uncertainty-inflation and tail-sampling tests for the velocity errors required to cross the threshold for interstellar identification; (2) back-integrate the trajectory with a more detailed Earth-Moon-Sun model; (3) refine the inbound velocity vector; and (4) if warranted, model atmospheric entry, fragmentation, and wind drift to estimate a fall footprint. Independent validation is especially important because it is the main way to test a gross-outlier failure mode.
Any ground-based optical, infrasound, seismic, satellite, or regional fireball-network observation from 2026–04–01 at 02:13:14 UTC could help verify the velocity measurement of Polar-IM and test its interstellar origin.
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https://www.nasa.gov/news-release/nasa-says-farewell-to-maven-mars-mission-hosts-media-call-today/
https://www.space.com/space-exploration/launches-spacecraft/nasas-maven-mars-orbiter-is-officially-dead-after-months-of-radio-silence
extra NASA
https://www.nasa.gov/blogs/spacestation/2026/06/02/bacteria-cartilage-and-metal-tops-tuesdays-research-aboard-station/
NASA Says Farewell to MAVEN Mars Mission, Hosts Media Call Today
Jun 03, 2026
The first mission devoted to observing the Martian atmosphere and its evolution, NASA’s MAVEN (Mars Atmosphere and Volatile Evolution), has ended after more than 11 years in orbit at Mars and a decade beyond its primary, one-year mission.
The spacecraft was heard last on Dec. 6, when it experienced an unexpected loss of signal after it passed behind the Red Planet.
NASA will host a media teleconference at 2 p.m. EDT today, Wednesday, June 3, to discuss MAVEN’s achievements.
The agency convened an anomaly review board in February to evaluate recovery efforts and assess the spacecraft’s probable current state.
The review board has determined that the MAVEN spacecraft is not recoverable, and it is no longer capable of performing its science and data relay mission, which is consistent with the mission team’s findings.
Telemetry from MAVEN prior to the spacecraft’s passage behind Mars in December showed all subsystems working normally. After the spacecraft emerged, NASA’s Deep Space Network (DSN) did not observe a signal.
A brief fragment of telemetry data from analysis of radio signals recorded by the DSN’s open-loop receivers indicated the spacecraft was in safe mode and rotating at an unusually high rate when it emerged from behind Mars, indicating a disruption in MAVEN’s orbit trajectory.
The review board concluded that due to this rotation, the batteries on the spacecraft had drained, causing the communications system to lose power and rendering MAVEN in an unrecoverable state.
These preliminary findings do not address a potential root cause for the anomaly, which still is being investigated. The review board is expected to provide its final report later this year.
NASA has begun the official process of decommissioning the MAVEN mission, following standard procedures to archive the full mission dataset for the science and exploration communities.
“The science MAVEN has given us is key to informing what kind of radiation protection and safety measures we must take before sending humans to Mars,” said Louise Prockter, director of the Planetary Science Division at NASA Headquarters in Washington.
“The data collected from MAVEN will continue to provide valuable insight into Mars for decades to come.”
Launched in November 2013, the MAVEN mission explored the Red Planet’s upper atmosphere, ionosphere, and interactions with the Sun to explore the loss of the Martian atmosphere to space.
Understanding atmospheric loss gives scientists insight into the history of the planet’s atmosphere and climate, liquid water, and planetary habitability.
“The MAVEN mission has truly advanced our understanding of the Martian atmosphere and evolution.
This dataset has had a tremendous impact on the field,” said Shannon Curry, MAVEN’s principal investigator and a researcher at the Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder.
“Our science team is exceptionally proud of all of these amazing discoveries.”
Sun’s impact on Mars
One of MAVEN’s first major results was that the erosion of Mars’ atmosphere increases significantly during solar storms.
The team studied how the solar wind, which is a stream of charged particles continually streaming from the Sun, and solar storms continually strip away Mars’ atmosphere, as well as how this process played a key role in altering the Martian climate from a potentially habitable world to today’s cold, arid planet.
The MAVEN mission made unprecedented strides in advancing our understanding of how the Sun and space weather affect Mars, as it was the only spacecraft that could simultaneously take measurements of both the Sun and the Martian atmospheric response.
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https://science.nasa.gov/earth/earth-observatory/typhoon-jangmi/
https://www.nasa.gov/directorates/stmd/prizes-challenges-crowdsourcing-program/center-of-excellence-for-collaborative-innovation-coeci/nasa-space-roboticist-challenge/
https://www.nasa.gov/image-article/look-up/
Martian light shows
The MAVEN mission discovered several types of auroras that light up when energetic particles plunge into the atmosphere, bombarding gases and making them glow.
The MAVEN team showed that protons create new kinds of auroras at Mars. On Earth, proton auroras only occur in very small regions near the poles, whereas at Mars they can occur everywhere.
Mars’ atmosphere sputters into space
To better understand how Mars lost most of its atmosphere, MAVEN measured atmospheric sputtering for the first time at any planet. The team did this by observing argon, which is a noble gas, meaning it rarely reacts with other constituents in the Martian atmosphere.
The only significant way it can be removed is by atmospheric sputtering, a process where ions crash into the Martian atmosphere at high enough speeds that they splash gas molecules out of the atmosphere, much like doing a cannonball into a pool.
The team used 11 years of data to reveal the presence of sputtered argon at high altitudes in the exact locations that the energetic particles crashed into the atmosphere, showing sputtering in real time.
Understanding Mars’ dusty secrets
In 2018, a series of dust storms created a dust cloud so large that it enveloped the Red Planet.
The MAVEN team studied how this “global” dust storm affected Mars’ upper atmosphere to understand how these events affected the escape of water to space.
It confirmed that heating from dust storms can loft water molecules far higher into the atmosphere than usual, leading to a sudden surge in water lost to space.
Chasing comets
In addition to Martian science, MAVEN contributed to NASA’s effort to observe comet 3I/ATLAS at Mars.
Over the course of 10 days last year, the MAVEN team designed a new observing campaign to capture 3I/ATLAS by taking multiple images of the comet in several wavelengths, much like using various filters on a camera.
Then it snapped high-resolution UV images to identify the hydrogen coming from the comet. By studying a combination of these images, scientists can identify a variety of molecules and better understand the comet’s composition and history.
During the mission’s lifetime, MAVEN’s science team produced more than 800 publications, and additional publications are planned.
In addition to science, the MAVEN spacecraft was an instrumental player in NASA’s Mars Relay Network, communicating data from Mars rovers to Earth. It also holds the solar system record for most data relayed from another planet in a single day.
Audio of today’s media teleconference will stream on the agency’s website at: https://www.nasa.gov/live
Participants in the teleconference include:
Tiffany Morgan, director, Mars Exploration Program, Planetary Science Division, NASA Headquarters
Mike Moreau, project manager, MAVEN, NASA’s Goddard Space Flight Center, Greenbelt, Maryland
Greg Heckler, deputy program manager for Capability Development, SCaN (Space Communications and Navigation), NASA Headquarters
Shannon Curry, MAVEN principal investigator, Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder
To ask questions by phone, media must RSVP no later than 12 p.m. to: sarah.frazier@nasa.gov. NASA’s media accreditation policy is available online.
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NASA’s Juno Reveals New Insights into Cosmic Ray Origins
June 3, 2026 11:05AM
Particles traveling close to the speed of light near Jupiter were captured by NASA’s Juno mission, providing new evidence for how and where high-energy particles, including cosmic rays, form.
Astronomers have sought the origins of cosmic rays since their discovery more than 100 years ago. These energetic particles can come from many sources, including supernovas and eruptions from the Sun.
When solar cosmic rays — commonly called solar energetic particles — reach Earth, they can trigger space weather effects that disrupt satellites, communications, and power systems.
NASA missions like MMS (Magnetospheric Multiscale) and THEMIS (Time History of Events and Macroscale Interactions during Substorms) showed how some electrons become highly energized in a region near Earth called the foreshock, where solar particles first encounter Earth’s magnetic field.
Scientists suspected the same process was responsible for accelerating high-energy particles in foreshocks at other planets and astrophysical systems, but they could not confirm it until now.
New observations around Jupiter provide direct confirmation of this process. While orbiting the gas giant, Juno measured high-speed electrons in Jupiter’s foreshock region.
These electrons reached even higher speeds than Earth’s, scaling with the giant planet’s larger-sized bow shock, formed when Jupiter’s magnetic field pushes through the stream of solar particles.
The results were published Wednesday in the journal Nature.
The scientists also found that this scaling relationship matched cosmic rays seen coming from supernovas across the galaxy, where even larger magnetic environments create even faster particles.
This suggests the same process occurring within the solar system can occur across the universe.
https://science.nasa.gov/blogs/science-news/2026/06/03/nasas-juno-reveals-new-insights-into-cosmic-ray-origins/
https://www.nature.com/articles/s41586-026-10473-z
extra extra NASA
https://nasawatch.com/history/freedom-250-vs-america-250-at-nasa/
https://www.morningstar.com/news/business-wire/20260603422961/union-pacific-railroads-newest-commemorative-locomotive-no-4547-embarks-on-first-freight-mission-hauling-artemis-iii-rocket-parts
https://www.space.com/space-exploration/human-spaceflight/happy-pride-month-remembering-sally-rides-historic-legacy-space-photo-of-the-day-for-june-3-2026
https://www.space.com/astronomy/stars/this-star-system-creates-a-rare-triple-eclipse-heres-what-that-would-look-like
US to quadruple size of Space Force command at air base in Japan
June 3, 2026
YOKOTA AIR BASE, Japan – U.S. Space Forces Japan is getting its own headquarters and another 60 guardians over the next year, according to its new commander.
Col. John Patrick took over the organization Wednesday morning from Col. Ryan Laughton during a ceremony at Yokota’s Enlisted Club. The unit, established in December 2024, is focused on communications, space resilience, navigation and missile defense.
“In the next year, if possible, we will grow to 80 personnel as soon as possible,” Patrick told reporters. The command now consists of 20 Space Force guardians.
Space Force has 116 guardians in units across Japan, 5th Air Force spokeswoman Air Force Capt. Tisha Yates said by email Wednesday afternoon.
The command has been working from the headquarters of U.S. Forces Japan but will soon move to its building on the air base, Yates said. President Donald Trump created the Space Force, the nation’s newest service branch, in December 2019.
Today, it has 9,400 active-duty guardians, according to its website. Its missions include tracking threats to the U.S. homeland and safeguarding American satellites.
Present at the command ceremony were USFJ commander Lt. Gen. Stephen Jost; 5th Air Force commander Lt. Gen. Joel Carey; Japan Aerospace Exploration Agency president Hiroshi Yamakawa; and Space Operations Wing commander Maj. Gen. Hiroshi Ishii of the Japan Air Self-Defense Force.
Patrick on Tuesday passed command of Space Forces Korea, a position he held since July 2024, to Col. Dorian Hatcher during a ceremony at Osan Air Base, south of Seoul.
There will be an increase in the number of exercises that Space Forces Japan will do with the joint force and with alliance partners and multinational partners, he said at Yokota.
The Air Self-Defense Force will soon be known as the Japan Air and Space Self-Defense Force, Patrick added. The name change “bodes well for the space domain and for Japan in elevating the importance of space,” he said.
Japan’s Space Operations Wing has about 670 personnel and will be upgraded to a space operations command with around 880 personnel before the end of March 2027, a Japanese air force spokesman said by phone Wednesday.
Some Japanese government officials speak to the media only on condition of anonymity. Space is no longer a benign environment, Patrick said. Russia began its ongoing war in Ukraine by launching a cyberattack on the country’s satellite operations.
Meanwhile, North Korea and China continue to develop space capabilities. “It is a contested, highly dynamic, war fighting domain,” and adversaries are rapidly expanding their counter-space capabilities, Patrick said. “Robust space defense is no longer a luxury,” he said.
“It is foundational to our way of life.” Patrick said he is concerned most with the rapidly growing capability of nations to launch satellites. “Having sensors and understanding what is in space and where it is at any specific time is a very difficult thing to do,” he said.
Brig. Gen. Brian Denaro, commander of the Hawaii-based U.S. Space Forces Indo-Pacific, presented Laughton with the Legion of Merit for his work at the Yokota command since its establishment.
Laughton is headed to the Pentagon, where he’ll serve as the Space Force’s chief of acquisition.
https://www.stripes.com/branches/space_force/2026-06-03/space-force-command-yokota-21860008.html
extra Space Force
https://www.patrick.spaceforce.mil/News/Article-Display/Article/4507375/guardian-mental-health-qa-with-ussfs-director-of-psychological-health/
https://www.vandenberg.spaceforce.mil/News/Article-Display/Article/4506712/afsec-brings-mishap-investigation-training-to-colorado-springs/
https://www.esa.int/Enabling_Support/Space_Engineering_Technology/Shaping_the_Future/Europe_advances_Pu-238_supply_chain_for_deep_space
extra ESA
https://www.esa.int/Enabling_Support/Space_Engineering_Technology/Shaping_the_Future/Inside_ESA_s_testing_of_the_m-NLP_instrument
https://www.youtube.com/watch?v=mAUDKldXDFs (ESA Astronaut Discusses Life in Space with European Media – Wednesday, June 3, 2026)
Europe advances Pu-238 supply chain for deep space
03/06/2026
An ESA-backed study confirmed that an independent European supply of the gold-standard fuel for deep-space missions, plutonium‑238 (Pu‑238), can be achieved using capabilities already in place today.
The study outlines how a shift from concept to action could transform Europe's existing nuclear expertise into a strategic space capability.
Optimum Pro, as the Endure project is known, conducted by Tractebel Engie with support from SCK CEN, examined the scientific, technical, regulatory, safety, economic and infrastructure needs of establishing a European supply chain for Pu-238.
The final report confirmed that production by ESA’s Member States is mainly technically and economically feasible with key existing infrastructure and sets out a road map from now until 2039 to ramp up production.
“Producing Pu-238 is feasible and the assets already exist in Europe,” said Brieuc Spindler, lead engineer at Tractebel Engie. He added that the studies have translated an initial idea into a robust, quantified roadmap supported by scientific and economic evidence.
“It’s not a matter of capabilities, we have the raw material and reactors to irradiate it and the knowhow and systems to do so.”
The roadmap shows the powerful concept that Europe already holds all the pieces needed to build a sovereign space nuclear capability.
From neptunium‑237 recovered in existing nuclear fuel cycles, to world-class research reactors such as Belgium’s BR2 and France’s upcoming Jules Horowitz Reactor, the continent possesses a ready-made ecosystem capable of supporting Pu‑238 production end-to-end.
How is nuclear rocket fuel produced
Producing Pu-238 begins with neptunium 237, a product already being recovered from nuclear fuel reprocessing but currently sent to the waste stream, which is formed into oxide pellets and prepared for irradiation.
These pellets are placed in a high neutron flux reactor where they absorb neutrons and gradually transform into Pu-238 through radioactive decay. After irradiation the material must cool for up to two years before chemical separation yields a purified product suitable for use in space power systems.
Unlike nuclear power generators these are research reactors, more often used to generate isotopes for medical research and treatments.
The study identified no major technical or safety barriers and even complex steps, such as target fabrication and isotope separation, have been successfully demonstrated at laboratory scale.
The main challenges the study identified were organisational: coordinating stakeholders, securing supply chains and aligning regulatory processes.
As ESA advances plans to explore low sunlight environments and develop long-term lunar and Martian presence, demand is growing for power systems that do not rely solely on solar energy.
Radioisotope power systems are widely regarded as mission-critical. Every Apollo mission, every Mars rover and most deep-space missions have relied on an atomic battery powered by Pu-238, a radioisotope produced in limited quantities in the United States and Russia.
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Two sides to ENDURE
ESA’s ENDURE programme was set up to do just this. The EuropeaN Devices Using Radioisotope Energy is ESA’s programme to develop Europe’s own radioactive isotope power capability.
Originally it only focused on developing systems using americium 241, seen at the time as the only viable option given geopolitical constraints on Pu-238 supply.
Despite recent breakthroughs, Pu-238 has still been widely regarded as the more effective isotope for radioisotope heat and power systems.
“On paper, plutonium has a better ratio of power to kilograms when you compare it with americium, meaning its power systems can be lighter and less bulky. It also only produces alpha radiation.
You can stop it with a sheet of paper, while americium needs to be encased in lead,” Brieuc says, detailing why plutonium is still the benchmark isotope for mission efficiency.
One of the issues foreseen with production of Plutonium-238 is that it reaches incredibly hot temperatures, which causes challenges for handling.
At least 300 grams of Pu 238 would be needed each year to meet ESA’s deep space mission portfolio needs.
While significant, the costs should only amount to a small percent of ESA’s annual budget – a substantial cost but one that is manageable with strategic long-term budgeting.
Kenza Benamar, the ESA R&D engineer for GSTP/Endure, shares that while the US, China, and South Korea are advancing nuclear power for space,
The absence of coordinated European investment in Pu‑238 production for space represents a missed opportunity to drive substantial scientific, industrial, and economic development across the region.
“Given the magnitude of the investment required, only a collective European initiative can ensure the establishment of Pu‑238 production for deep space exploration, delivering substantial economic impact across the region, strengthening international cooperation, and enabling access to the farthest reaches of our solar system,” says Kenza.
Lighter and more efficient
“Pu-238 may be more expensive upfront but it might make missions cheaper ultimately because it gives more power per kilogram,” explains Ruben Van Parys, a lead engineer on the project from Tractebel.
because its high power to mass ratio allows spacecraft to be lighter and more efficient, an advantage that becomes critical for missions to distant destinations such as the moons of Jupiter.
“Europe doesn’t just want to reach the Moon, others are already on that path. It wants to survive the lunar night, which would be a real differentiator. That technology doesn’t exist anywhere else. If we are on the Moon, with that capability it would set Europe apart.
Having a system that can endure those extreme conditions opens the door not just for the Moon but for deep space, its exciting,” Brieuc enthuses. “But as you go further out, the power-to-mass ratio becomes critical and you have to stay as light as possible.
If 1 kg to the Moon already costs around a million Euros, going all the way to the moons of Jupiter makes that constraint even more extreme. That’s where plutonium‑238 becomes a true enabler, making these ambitious deep-space missions possible.”
“It would be a miss if we don’t jump on this train in Europe, because we already have the tools and the capability to start production,” Brieuc concludes.
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Several wounded by Ukrainian drone attacks on St. Petersburg ahead of ‘Russian Davos’
Updated 3 Jun, 2026 10:34
Ukrainian drone attacks on St. Petersburg have left several people wounded, local governor Aleksandr Beglov has said.
The wave of strikes coincided with the opening day of Russia’s largest international investment forum, which will host thousands of guests from around the world over the coming days.
UAVs targeted infrastructure in the Kirovsky and Krasnoselsky districts as well in the port of Kronstadt, Beglov wrote in a post on Telegram on Wednesday morning.
Response teams have been deployed to the facilities damaged by the attacks, he added.
The 29th St. Petersburg International Economic Forum (SPIEF 2026), often referred to as the ‘Russian Davos’, is taking place from June 3 to 6 and will be attended by around 20,000 businesspeople, politicians, and public figures from more than 100 nations.
Russian President Vladimir Putin is scheduled to address the gathering on Friday.
In Leningrad Region, which surrounds St. Petersburg, at least 59 Ukrainian drones were shot down overnight, local governor Aleksandr Drozdenko has said. Several private homes suffered minor damage due to falling debris, but there were no injuries, he added.
In total, 345 Ukrainian UAVs were shot down across Russia overnight as the country came under another large-scale attack, the Defense Ministry reported.
The interceptions took place over Moscow, Leningrad, Belgorod, Bryansk, Voronezh, Kaluga, Kursk, Novgorod, Orel, Pskov, Rostov, Smolensk, Tver, Tula, and Krasnodar regions, as well as over Crimea and the Sea of Azov, the ministry said.
In Russia’s Donetsk People’s Republic, seven civilians were killed and 11 others wounded when a Ukrainian drone stuck a passenger bus traveling from Crimea to Moscow.
Ukrainian UAVs have targeted Leningrad Region, particularly its energy facilities, on numerous occasions in recent months, with the explosive-laden drones often reaching northwestern Russia via Latvia, Estonia, Lithuania and Finland. Some of them have crashed inside the NATO countries.
Russian Security Council Secretary Sergey Shoigu warned previously that if it turns out that the Baltic States and Finland “deliberately provide their airspace” to Ukrainian UAVs, Moscow has the right to self-defense in response to an “armed attack” under Article 51 of the UN Charter.
https://www.rt.com/russia/640900-petersburg-spief-ukraine-drone/
extra RT
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