TYB's
NASA Astronomy Picture of the Day
November 25, 2025
Comet Lemmon and the Milky Way
What did Comet Lemmon look like when it was at its best? One example is pictured here, featuring three celestial spectacles all at different distances. The closest spectacle is the snowcapped Meili Mountains, part of the Himalayas in China. The middle marvel is Comet Lemmon near its picturesque best early this month, showing not only a white dust tail trailing off to the right but its blue solar wind-distorted ion tail trailing off to the left. Far in the distance on the left is the magnificent central plane of our Milky Way Galaxy, featuring dark dust, red nebula, and including billions of Sun-like stars. Comet C/2025 A6 (Lemmon) is already fading as it heads back into the outer Solar System, while the Himalayan mountains will gradually erode over the next billion years. The Milky Way Galaxy, though, will live on forming new mountains and comets for many billions of years into the future.
https://apod.nasa.gov/apod/astropix.html
Space Weather, Big Volcano, Science Mystery | S0 News and frens
Nov.25.2025
https://www.youtube.com/watch?v=LPT8K_Ae5y8
https://x.com/SunWeatherMan/status/1993305900694831403
https://x.com/StefanBurnsGeo/status/1993015690157269232
https://x.com/JonnyKimUSA/status/1993136558250377271
https://www.space.com/stargazing/auroras/northern-lights-may-be-visible-in-14-states-tonight
https://www.space.com/live/aurora-forecast-will-the-northern-lights-be-visible-tonight
https://spaceweathernews.com/
https://www.swpc.noaa.gov/
The term soup sandwich always cracks me up.
Like, who came up with that?
What does one even look like?
kek
Good, now quit bombing everything
Clearest Photo Yet of 3I/ATLAS Taken by Canadian Astrophotographer
24 November 2025, 9:16 PM GMT
A Canadian astrophotographer has captured what may be the clearest image yet of interstellar object 3I/ATLAS, fuelling a fierce debate led by a Harvard astronomer who claims the object is not a comet but alien technology.
Paul Craggs, the astrographer in question, shared what might be the clearest images of 3I/ATLAS yet in recent posts on X (formerly known as Twitter).
In a post on 22 November, Craggs shared three images of the interstellar comet using his Dwarf 3 telescope. The photos show a much clearer shape to the comet and seem to show a lack of a cometary tail.
Craggs's photos come at a time when space enthusiasts and astrophotographers have been sharing their images of the comet, likely clearer than the images NASA has released thus far.
The US space agency released more images of 3I/ATLAS during a livestream event on 19 November following the reopening of the federal government.
The Alien Artefact Theory
The discussion around 3I/ATLAS is not without speculation that the comet may not actually be a comet but something else.
This theory has been championed by Harvard astronomer Professor Avi Loeb, who has listed 13 anomalies in the comet, classifying each anomaly into three categories: Minor, medium, and major.
Six of which, Professor Loeb classifies as major, and go beyond mere speculation.
According to Professor Loeb, the unusual behaviour of the comet, from its improbable trajectory to its strange jet structures, indicates that 3I/ATLAS is more than what it seems.
'It is apparent that 3I/ATLAS is an extremely rare and mysterious object, especially if it happens to be a natural comet, as argued by NASA officials at the press conference on 19 November 2025,' said Professor Loeb in a post on Medium.
The Harvard astronomer also touched on whether scientists can broadcast a signal at the comet and expect a response.
'Obviously, one can shoot a laser beam or some radar signal and wait for an answer, but I think it would be more informative for us to figure out remotely what it is by taking a lot of data of it with hundreds of ground-based telescopes and the Hubble and Webb telescopes as well,' said Professor Loeb.
NASA Releases Photos of 3I/ATLAS Taken from Mars
NASA became the latest of three space agencies to release their images of 3I/ATLAS, following photos released by the European Space Agency (ESA) and the China National Space Agency (CNSA).
The US agency's images of 3I/ATLAS were taken by its Mars missions; the Mars Reconnaissance Orbiter, the Mars Atmosphere and Volatile EvolutioN (MAVEN), and the Perseverance Rover.
The two orbiters captured the interstellar comet in both optical and ultraviolet light, respectively, while the rover captured a faint image of the comet.
The MRO took images of 3I/ATLAS using the HiRISE camera when the comet was 0.2 astronomical units away, perhaps the closest that a NASA spacecraft has gotten to the comet.
'Observations of interstellar objects are still rare enough that we learn something new on every occasion. We're fortunate that 3I/ATLAS passed this close to Mars,' said Shane Byrne, the HiRISE principal investigator at the University of Arizona.
'One of MRO's biggest contributions to NASA's work on Mars has been watching surface phenomena that only HiRISE can see,' said MRO project scientist Leslie Tamppari of NASA's Jet Propulsion Laboratory.
'This is one of those occasions where we get to study a passing space object as well.'
https://www.ibtimes.co.uk/clearest-photo-yet-3i-atlas-taken-canadian-astrophotographer-1757702
https://usaherald.com/3i-atlas-unprecedented-morphology-challenges-everything-we-know-about-comets/
https://twitter.com/craggs_paul/status/1992358856274612486
https://x.com/RedCollie1/status/1992718721551679693
https://x.com/UAPWatchers/status/1993323596605747314
https://www.youtube.com/watch?v=s2TcX8aah1c (John Lenard Walson: @3iAtlas #3IATLAS #3i/ATLAS )
moar ATLAS
Images of 3I/ATLAS on November 22–24, 2025
November 25, 2025
A number of images of the interstellar object 3I/ATLAS were taken on November 22–24, 2205 by amateur astronomers and astrophotographers. They consistently show a glowing coma with tightly-collimated anti-tail and tail.
The best image (available here) was taken by Mitsunori Tsumura on November 22 at 19:25 UTC with a 0.5-meter telescope.
Given the current distance of 3I/ATLAS from Earth of 300 million kilometers, its tail appears to extend out to 5 million kilometers whereas the sunward anti-tail extends out to about a million kilometers.
It takes a month to cross a million kilometers at a speed of 400 meters per second.
The huge extent of the anti-tail towards the Sun implies that it carries a large enough momentum flux to penetrate through the solar wind. The anti-tail’s ram-pressure exceeds that of the solar wind out to that distance.
The solar wind is flowing at a speed of about 400 kilometers per second, which is at least a thousand times faster than the thermal speed of outflowing gas from a natural comet at the location of 3I/ATLAS.
Since ram-pressure scales as the gas speed squared, this means that the outermost mass density in the anti-tail is a million times bigger than the solar wind density of a few proton masses per cubic centimeters.
For a natural comet, the outermost mass density of the anti-tail implies a mass flux of 200 tons per second per square area of size 0.3-million kilometer on a side.
Counting also the tail, this yields a total mass loss rate of about a few billion tons over the past two months.
For a natural comet, the estimated mass loss over the months of October and November 2025 is about 10% of the minimum mass associated with 3I/ATLAS, 33 billion tons — that I calculated here based on the lack of non-gravitational acceleration during the months of July, August and September 2025.
Any such acceleration would stem from the anisotropy in the mass loss rate times the outflow speed, divided by the object mass. Since then, a non-gravitational acceleration was actually measured around perihelion in October 2025.
By now its detection, reported here by JPL Horizons, is statistically significant at ten standard deviations.
Momentum conservation at the maximum thermal gas speed of 400 meters per second implies that the measured level of non-gravitational acceleration requires more than 10% of the mass of 3I/ATLAS to be lost if it is a natural comet, as I showed here.
Jets from technological thrusters could be more effective in accelerating 3I/ATLAS with less mass loss, as they produce higher exhaust speeds.
The required mass loss to penetrate through the solar wind is scaled down by the square of the increased outflow speed.
This corresponds to 2 or 4 orders of magnitude reduction in mass loss for chemical thrusters or ion thrusters, respectively.
Future spectroscopic measurements could assess the speed of the jets and distinguish between the natural sublimation of pockets of ice by sunlight and technological alternatives.
The unusually elongated appearance of 3I/ATLAS, as reported here by Paul Craggs on November 22, 2025, might have resulted from motion smearing of the image.
Two other images consistent with the anti-tail/tail morphology were taken by Peter Carson Leigh at 5:28 UTC on November 22, 2025 with a 0.315-meter telescope in Spain and by Elena Walter at 8:05 UTC on November 24, 2025 with a 0.432-meter telescope in Chile.
We are all awaiting better images from the largest telescopes on Earth, as well as from the Hubble and Webb Space Telescopes, near 3I/ATLAS’s closest approach to Earth on December 19, 2025 at a minimum distance of 269 million kilometers.
The best is yet to come. The data collected in December 2025 will set the verdict on the nature of 3I/ATLAS.
In addition, we will be able to assess whether 3I/ATLAS is forecasted to reach the Hill radius of Jupiter on March 16, 2025 — as discussed here, to better than four significant digits.
https://avi-loeb.medium.com/images-of-3i-atlas-on-november-22-24-2025-5026e8b73a02
https://www.ibtimes.co.uk/3i-atlas-structural-features-never-documented-any-known-celestial-object-1757914
https://www.geo.tv/latest/635445-interstellar-object-3iatlas-deploying-satellites-to-spy-on-jupiter
https://x.com/Truthpolex/status/1993094055761424482
https://x.com/4biddnKnowledge
https://www.youtube.com/watch?v=YSDoYGR8A3A (Leak Project: "THIS IS CRAZY!" Latest Images of 3I/ATLAS)
The other ATLAS
Watch fractured comet C/2025 K1 (ATLAS) race away from the sun in free livestream tonight
November 24, 2025
Tune in on Nov. 24 to watch live telescopic views of the fractured comet C/2025 K1 (ATLAS), which recently broke into multiple large pieces following a close brush with the sun.
The livestream, courtesy of the Virtual Telescope Project, begins at 10 p.m. EST on Nov. 24 (0300 GMT on Nov. 25) and will feature live views of C/2025 K1 (ATLAS) from the organization's suite of robotic telescopes located in Manciano, Italy, weather permitting.
Comet C/2025 K1 (ATLAS) was discovered barrelling towards the sun on May 24, 2025 and is believed to have originated from the Oort cloud — a frozen shell made up of billions of icy bodies that surrounds the solar system.
The comet reached perihelion, its closest approach to the sun, on Oct. 8, when it passed just 31 million miles (50 million kilometers) from our star.
On the night of Nov. 11, astronomers watched as the object dramatically fractured into at least three large pieces, likely as a result of the intense heating it absorbed at perihelion, which may have undermined the structural stability of its central nucleus.
Comet C/2025 K1 (ATLAS) is not in any way related to the interstellar comet 3I/ATLAS, which was confirmed in July to be just the third body to visit our solar system.
Rather, the shared "ATLAS" designation stems from the fact that they were both found by the NASA-funded Asteroid Terrestrial-Impact Last Alert System (ATLAS) program.
The fractured comet is currently too dim to be seen by the naked eye, but can still be spotted with the aid of a small backyard telescope close to the stars of the famous Big Dipper asterism in the constellation Ursa Major, or captured in long exposure photography!
Astrophotographers should check out our guide detailing how to image comets, along with our roundups of the best lenses and cameras for capturing the night sky and the best deals available in the run up to Black Friday 2025.
https://www.space.com/stargazing/watch-fractured-comet-c-2025-k1-atlas-race-away-from-the-sun-in-free-livestream-tonight
https://www.virtualtelescope.eu/2025/11/17/comet-c-2025-k1-atlas-the-broken-comet-online-observation-25-nov-2025/
https://x.com/MrMBB333/status/1992996690522218747
https://x.com/aquinasduffy/status/1993328579396911520
https://x.com/PFKHealth/status/1993229907342590382
https://www.youtube.com/watch?v=UwAGiJRHKCE (The Virtual Telescope Project: Comet C/2025 K1 ATLAS: the broken comet – online observation (25 Nov. 2025))
NASA’s OSIRIS-APEX Spacecraft Slingshots Past Earth
November 25, 2025
At 1:00 p.m. EDT on Tuesday, Sept. 23, NASA’s OSIRIS-APEX (Origins, Spectral Interpretation, Resource Identification, and Security – Apophis Explorer) spacecraft flew within 2,136 miles (3,438 kilometers) of Earth.
During approach and as OSIRIS-APEX passed Earth, it looked home, capturing images and data of our home planet to help calibrate its science instruments.
During the spacecraft’s primary mission, the StowCam instrument was used to verify the capsule full of sample from asteroid Bennu was safely stowed and prepared to journey back to Earth.
Now, StowCam provides a view of the instrument panel, including the OSIRIS-REx Laser Altimeter, provided by the CSA (Canadian Space Agency) to create detailed 3D topographical maps of Bennu.
https://science.nasa.gov/blogs/osiris-apex/2025/11/25/nasas-osiris-apex-spacecraft-slingshots-past-earth/
https://spaceflightnow.com/2025/11/24/nasa-boeing-pivot-starliner-1-mission-from-4-person-astronaut-flight-to-cargo-only/
https://www.ndtv.com/world-news/after-sunita-williams-and-butch-wilmores-extended-mission-nasa-boeing-keep-crew-off-next-starliner-flight-9694516
NASA, Boeing pivot Starliner-1 mission from 4-person astronaut flight to cargo-only
November 24, 2025
In its latest shakeup to the Commercial Crew Program, NASA announced on Monday it has reduced the number of missions Boeing is required to fly to the International Space Station and changing the next flight from a crew mission to a cargo mission.
The original contract NASA awarded to Boeing and SpaceX called for each to fly an uncrewed demonstration flight to the ISS, followed by a crewed demo mission and then conduct six regular crew rotation missions.
Both companies launched their uncrewed demo flights in 2019, but their trajectories split dramatically after that.
SpaceX was able to proceed to its crewed demo mission with its Dragon spacecraft, named Demo-2, in May 2020 and has so far flown 12 NASA crew missions to the orbiting outpost.
Meanwhile Boeing needed to repeat its uncrewed flight in 2022, dubbed Orbital Flight Test 2 (OFT-2), because the 2019 Orbital Flight Test ran into issues that prevented the spacecraft from reaching the space station.
The 2024 Crew Flight Test (CFT) also encountered multiple issues, mainly associated with the Starliner’s thrusters, which ultimately resulted in NASA ordering the capsule to return without a crew in September and the CFT astronauts coming home in a SpaceX Dragon capsule.
Since the conclusion of the Starliner CFT mission, NASA and Boeing have debated whether the next flight of Starliner would carry astronauts or not, with each public statement from NASA casting increasing doubt on a crewed flight.
Monday’s announcement made it official that the mission, dubbed Starliner-1, would be a cargo-only flight to the ISS, scheduled to launch no earlier than April 2026.
“NASA and Boeing are continuing to rigorously test the Starliner propulsion system in preparation for two potential flights next year,” said Steve Stich, manager of NASA’s Commercial Crew Program in a statement.
“This modification allows NASA and Boeing to focus on safely certifying the system in 2026, execute Starliner’s first crew rotation when ready, and align our ongoing flight planning for future Starliner missions based on station’s operational needs through 2030.”
NASA and Boeing also agreed to reduce the number of flights NASA’s is obligated to buy from Boeing from six down to four “with the remaining two available as options.”
And with the decision for Starliner-1 to be cargo only, that means NASA may only have three flights with Starliner that will carry its astronauts to the ISS.
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If Starliner-1 is a nominal flight, it opens the door for Starliner-2 to become Boeing’s first operational mission to the space station with crew onboard.
“The next commercial flight to the International Space Station without a specific provider assigned is targeted no earlier than October 2026.
This flight will handover with NASA’s SpaceX Crew-12 mission, which is targeted to launch in early 2026,” a NASA spokesperson said.
What about the astronauts?
The next crew of a Boeing CST-100 Starliner spacecraft is now somewhat of a mystery, at least from a public perspective.
Scott Tingle, the NASA astronaut who was named Starliner-1 commander in September 2022 was named as the newest chief of NASA’s Astronaut Office this month.
When Tingle was announced, the agency also said astronaut Mike Fincke would be the Starliner-1 pilot.
However, he and Japan Aerospace Exploration Agency (JAXA) astronaut Kimiya Yui, another astronaut assigned to Starliner-1, were both tasked to fly as members of the SpaceX Crew-11 mission, which is currently in progress.
Spaceflight Now reached out to the Canadian Space Agency to see learn more about the fate of its astronaut, Joshua Kutryk, who was assigned to fly the Starliner-1 mission as a mission specialist. We’re waiting to hear back.
Eric Berger, Ars Technica’s senior space reporter, reported last week that NASA astronaut Luke Delaney was also in line to train for the Starliner-1 mission at one point, but has been reassigned to the SpaceX Crew-13 mission.
There are some astronauts who have trained to fly on Starliner and were reassigned to fly on SpaceX’s Dragon spacecraft who could conceivably be assigned to the Starliner-2 flight, assuming all goes well with this next cargo mission.
Nicole Mann was one of the original members of the Starliner Crew Flight Test mission before being tasked to SpaceX Crew-5. She was picked alongside NASA astronaut Eric Boe who withdrew for medical reasons a the time.
The only other active astronaut who has been publicly confirmed to have trained on the Starliner systems is CFT Pilot Sunita ‘Suni’ Williams.
However, given that Starliner-2 would be her fourth mission after already accumulating more than 600 days in space, she may run up against radiation limits for NASA astronauts.
Below are the list of astronauts who have retired from active service who trained to fly on Starliner (either for CFT or Starliner-1):
Josh Cassada
Jeanette Epps
Chris Ferguson
Koichi Wakata (JAXA)
Barry ‘Butch’ Wilmore
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Soyuz Rocket Rolls Out as Cygnus Parks Away from Station
November 24, 2025
A Soyuz rocket rolled out to its launch pad at the Baikonur Cosmodrome in Kazakhstan today to begin counting down to a Thanksgiving Day liftoff of three new crew members to the International Space Station.
NASA astronaut Chris Williams and Roscosmos cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev are scheduled to lift off aboard the Soyuz MS-28 spacecraft at 4:27 a.m. EDT (3:27 p.m. Baikonur time) on Thursday, Nov. 27.
They will orbit Earth twice before docking to the Rassvet module at 7:38 a.m. the same day beginning an eight-month space research mission.
The Cygnus XL spacecraft, supporting the Northrop Grumman-23 commercial resupply services mission for NASA, was uninstalled today from the International Space Station.
It will remain attached to the station’s Canadarm2 robotic arm until Monday, Dec. 1, clearing the way for the arrival of the crewed Roscosmos Soyuz MS-28 spacecraft on Thursday.
NASA, Northrop Grumman, and Roscosmos coordinated the spacecraft’s movement to prevent any unnecessary structural loads from being imparted on Cygnus XL and its solar arrays when the Soyuz MS-28 spacecraft docks to the Rassvet module, which is the adjacent docking port.
The on-duty robotics officer in the Mission Control Center at NASA’s Johnson Space Center in Houston completed the maneuver, while agency astronauts Jonny Kim and Zena Cardman monitored from inside the space station.
Cygnus XL will be reattached to the space station on Dec. 1 and remain there until no earlier than March 2026, when it is scheduled to depart and dispose of several thousand pounds of trash during its destructive re-entry into Earth’s atmosphere.
Kim earlier worked out on the advanced resistive exercise device for one part of the CIPHER investigation that is studying cardiorespiratory fitness, muscle strength, and endurance in microgravity.
Cardman injected gas into a specialized tank for a fluid physics experiment that is testing ways to protect super-cooled fluids, or cryogenic fluids, in space.
Flight Engineers Mike Fincke of NASA and Kimiya Yui of JAXA (Japan Aerospace Exploration Agency) joined each other on Monday and continued offloading some of the several thousand pounds of new science and supplies delivered aboard the HTV-X1 cargo spacecraft on Oct. 29.
Yui also familiarized himself with the operations of the Astrobee robotic helpers before replacing components inside the Tranquility module’s bathroom, or waste and hygiene compartment.
Fincke also trained to use the Astrobees then set up the fluorescence microscope to observe how particles behave inside fluids.
Roscosmos cosmonauts Sergey Ryzhikov and Alexey Zubritsky, station Commander and Flight Engineer respectively, both tested the lower body negative pressure suit for its ability to reverse the space-caused flow of body fluids toward a crew member’s head.
Results may prevent microgravity-induced head and eye pressure and help crews adjust quicker to the return to Earth’s gravity.
Roscosmos Flight Engineer Oleg Platonov wore virtual reality googles and sensors while responding to visual signals to observe how his vision and sense of balance are adjusting to microgravity.
https://www.nasa.gov/blogs/spacestation/2025/11/24/soyuz-rocket-rolls-out-as-cygnus-parks-away-from-station/
NASA’s Mars-bound ESCAPADE Mission Captures First ‘Selfies’
November 24, 2025
About a week after its launch, NASA’s ESCAPADE (Escape and Plasma Acceleration and Dynamics Explorers) mission has already captured its first images: a pair of self-portraits showing part of the spacecraft as the twin explorers speed away from Earth.
On Nov. 21, one of the two ESCAPADE spacecraft used its Visible and Infrared Observation System (VISIONS) cameras, provided by Northern Arizona University in Flagstaff, to capture these images, showing part of a solar panel on the spacecraft.
The images prove the cameras are working well. The visible-light image also suggests that the spacecraft should have the sensitivity to image Martian aurora from orbit.
The infrared camera will be used at Mars to better understand how materials on the surface heat up and cool down during Mars’ day-night cycle and over the planet’s seasons.
The second ESCAPADE spacecraft also successfully took its first photos, but it was targeted toward deep space, so the images were simply black.
The twin ESCAPADE spacecraft, built by Rocket Lab and ultimately bound for Mars, launched on Nov. 13 aboard a Blue Origin New Glenn rocket from Cape Canaveral Space Force Station in Florida.
Once the ESCAPADE spacecraft reach Mars, they will study how a million-mile-per-hour stream of material flowing from the Sun, known as the solar wind, interacts with the Martian environment and how that drives atmospheric loss at the Red Planet.
Before they head for Mars, though, the two spacecraft are following a “loiter” or “Earth-proximity” orbit around a location in space about a million miles from Earth called Lagrange point 2.
In November 2026, they will return to Earth to use our planet’s gravity to slingshot their way to Mars. They will arrive at the Red Planet in September 2027.
https://science.nasa.gov/blogs/escapade/2025/11/24/nasas-mars-bound-escapade-mission-captures-first-selfies/
New NASA HEAT and My NASA Data Resources Bring Space Weather Science into Classrooms
Nov 24, 2025
As the Sun enters a period of heightened activity, students now have a new way to explore its powerful effects on Earth and space.
NASA’s Heliophysics Education Activation Team (NASA HEAT), in collaboration with My NASA Data, has released a new set of classroom resources that invite students and educators to engage with real NASA mission data to study space weather phenomena in real time.
Hands-On Learning with Real NASA Data
Developed as part of NASA HEAT’s mission to increase awareness and understanding of heliophysics, these new materials help learners connect directly with the science of the Sun and its influence on the solar system.
The resources include:
Lesson plans and mini-lessons for quick classroom engagement
Interactive web-based tools that let students visualize and analyze real mission data
StoryMaps, longer-form digital experiences that guide multi-day investigations into space weather events
These activities draw from data collected by NASA’s Parker Solar Probe, the Solar Dynamics Observatory (SDO), and the European Space Agency’s Solar Orbiter, among others, giving students a chance to explore how scientists monitor and study the Sun’s behavior.
Understanding Space Weather
Space weather is driven by the Sun’s activity – its bursts of energy, radiation, and plasma that stream through space.
When these events interact with Earth’s magnetic field, they can produce stunning auroras but also cause radio disruptions, satellite interference, and power grid issues.
By engaging with these new resources, students can learn how NASA monitors and predicts these solar phenomena and why studying space weather is essential for keeping astronauts, spacecraft, and technology safe.
Learning During Solar Maximum
This launch comes at a perfect time. In late 2024, the Sun entered solar maximum, the most active part of its 11-year cycle, providing students a front-row seat to increased solar flares, sunspots, and coronal mass ejections.
The new NASA HEAT and My NASA Data resources encourage educators to use this unique moment to deepen classroom discussions on magnetism, energy, and the Sun–Earth connection through observation and data-driven exploration.
Inspiring Future Scientists
Both NASA HEAT and My NASA Data, part of GLOBE Mission Earth (Global Learning and Observations to Benefit the Environment), are part of the NASA Science Activation (SciAct) program, which connects learners of all ages with authentic NASA science content, experts, and experiences.
By bringing real-world data and current scientific phenomena into the classroom, these new tools empower students to think like scientists and see themselves as contributors to ongoing discovery.
https://science.nasa.gov/learning-resources/science-activation/new-nasa-heat-and-my-nasa-data-resources-bring-space-weather-science-into-classrooms/
https://www.miragenews.com/nasa-tools-introduce-space-weather-to-classrooms-1576865/
somebody has to do it
https://science.nasa.gov/earth/nasa-noaa-rank-2025-ozone-hole-as-5th-smallest-since-1992/
https://www.youtube.com/watch?v=FQQ1UzFFetk
NASA, NOAA Rank 2025 Ozone Hole as 5th Smallest Since 1992
Nov 24, 2025
While continental in scale, the ozone hole over the Antarctic was small in 2025 compared to previous years and remains on track to recover later this century, NASA and the National Oceanic and Atmospheric Administration (NOAA) reported.
The hole this year was the fifth smallest since 1992, the year a landmark international agreement to phase out ozone-depleting chemicals began to take effect.
At the height of this year’s depletion season from Sept. 7 through Oct. 13, the average extent of the ozone hole was about 7.23 million square miles (18.71 million square kilometers) — that’s twice the area of the contiguous United States.
The 2025 ozone hole is already breaking up, nearly three weeks earlier than usual during the past decade.
The hole reached its greatest one-day extent for the year on Sept. 9 at 8.83 million square miles (22.86 million square kilometers).
It was about 30% smaller than the largest hole ever observed, which occurred in 2006, and had an average area of 10.27 million square miles (26.60 million square kilometers).
“As predicted, we’re seeing ozone holes trending smaller in area than they were in the early 2000s,” said Paul Newman, a senior scientist with the University of Maryland, Baltimore County, and leader of the ozone research team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
“They’re forming later in the season and breaking up earlier. But we still have a long way to go before it recovers to 1980s levels.”
NASA and NOAA scientists say this year’s monitoring showed that controls on ozone-depleting chemical compounds established by the Montreal Protocol and subsequent amendments are driving the gradual recovery of the ozone layer in the stratosphere, which remains on track to recover fully later this century.
The ozone-rich layer acts as a planetary sunscreen that helps shield life from harmful ultraviolet (UV) radiation from the Sun. It is located in the stratosphere, which is found between 7 and 31 miles above the Earth’s surface.
Reduced ozone allows more UV rays to reach the surface, resulting in crop damage as well as increased cases of skin cancer and cataracts, among other adverse health impacts.
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The ozone depletion process starts when human-made compounds containing chlorine and bromine rise high into the stratosphere miles above Earth’s surface.
Freed from their molecular bonds by the more intense UV radiation, the chlorine and bromine-containing molecules then participate in reactions that destroy ozone molecules.
Chlorofluorocarbons and other ozone-depleting compounds were once widely used in aerosol sprays, foams, air conditioners, and refrigerators. The chlorine and bromine from these compounds can linger in the atmosphere for decades to centuries.
“Since peaking around the year 2000, levels of ozone-depleting substances in the Antarctic stratosphere have declined by about a third, relative to pre-ozone-hole levels,” said Stephen Montzka, a senior scientist with NOAA’s Global Monitoring Laboratory.
As part of the 1987 Montreal Protocol, countries agreed to replace ozone-depleting substances with less harmful alternatives.
“This year’s hole would have been more than one million square miles larger if there was still as much chlorine in the stratosphere as there was 25 years ago,” Newman said.
Still, the now-banned chemicals persist in old products like building insulation and in landfills. As emissions from those legacy uses taper off over time, projections show the ozone hole over the Antarctic recovering around the late 2060s.
NASA and NOAA previously ranked ozone hole severity using a time frame dating back to 1979, when scientists began tracking Antarctic ozone levels with satellites. Using that longer record, this year’s hole area ranked 14th smallest over 46 years of observations.
Factors like temperature, weather, and the strength of the wind encircling Antarctica known as the polar vortex also influence ozone levels from year to year.
A weaker-than-normal polar vortex this August helped keep temperatures above average and likely contributed to a smaller ozone hole, said Laura Ciasto, a meteorologist with NOAA’s Climate Prediction Center.
Researchers monitor the ozone layer around the world using instruments on NASA’s Aura satellite, the NOAA-20 and NOAA-21 satellites, and the Suomi National Polar-orbiting Partnership satellite, jointly operated by NASA and NOAA.
NOAA scientists also use instruments carried on weather balloons and upward-looking surface-based instruments to measure stratospheric ozone directly above the South Pole Atmospheric Baseline Observatory.
Balloon data showed that the ozone concentration reached its lowest value of 147 Dobson Units this year on Oct. 6. The lowest value ever recorded over the South Pole was 92 Dobson Units in October 2006.
The Dobson Unit is a measurement that indicates the total number of ozone molecules present throughout the atmosphere above a certain location.
A measurement of 100 Dobson Units corresponds to a layer of pure ozone 1 millimeter thick — about as thick as a dime — at standard temperature and pressure conditions.
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