For 18-year-old Hailey Macleod, access to Edwards Air Force Base, Calif., was the realization of a dream with the help of a wish granter at Make-A-Wish Greater Los Angeles and the 412th Test Wing.
Source: www.war.gov
Signers of the Declaration of Independence: Connecticut, Part 1
Samuel Huntington and Roger Sherman are two of the four Connecticut delegates among the 56 Founding Fathers who signed the Declaration of Independence on July 4, 1776.
Source: www.war.gov
NASA Welcomes San Marino Signing the Artemis Accords
Minister of Industry and Technological Research Rossano Fabbri signed on behalf of San Marino. Gregory Mann, NASA Europe representative, and U.S. Consul General in Florence Joseph Tordella participated in the event on Friday, Sept. 25, 2026.
Credit: U.S. Department of State
The Republic of San Marino became the 76th signatory to the Artemis Accords during a ceremony in the city of Rimini on Friday with NASA and U.S. Department of State officials present.
“San Marino joins a growing coalition of like-minded nations committed to the peaceful, transparent, and responsible exploration of space,” said NASA Deputy Administrator Matt Anderson. “President Trump has directed NASA to build a Moon Base and establish an enduring presence on the lunar surface. As we do, we are putting the principles of the Accords into practice. NASA has invited every Artemis Accords signatory to participate in our return to the Moon through scientific payloads, technology demonstrations, CubeSats, and other capabilities. San Marino is already looking toward that future.”
Minister of Industry and Technological Research Rossano Fabbri signed on behalf of San Marino. Gregory Mann, NASA Europe representative, participated in the ceremony with the U.S. Consul General in Florence Joseph Tordella.
“We are pleased and honored that the Republic of San Marino has been welcomed as the 76th signatory state of the Artemis Accords,” said Fabbri. “We fully share the principles and values expressed in the Artemis Accords, and we are convinced that the signatory states united under the Accords will make a tangible contribution to promoting international cooperation in space and ensuring the use of space for peaceful purposes.”
In 2020, NASA and the State Department joined with seven other founding nations to establish the Artemis Accords, responding to the growing interest in lunar activities by both governments and private companies. They introduced the first set of practical principles aimed at enhancing the safety and coordination between nations as they explore the Moon, Mars, and beyond, committing nations to:
- Explore peaceably and transparently
- Render aid to those in need
- Enable access to scientific data
- Ensure activities do not interfere with those of others
- Preserve historically significant sites and artifacts by developing best practices
By signing the Artemis Accords, nations open the door to opportunities for future lunar exploration with NASA, advancing humanity’s return to the Moon, and shaping the Golden Age of exploration and innovation.
Learn more about the Artemis Accords at:
https://www.nasa.gov/artemis-accords
Source: www.nasa.gov
APOD: 2026 September 26 – Mirrored Meteor and Milky Way
APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Mirrored Meteor and Milky Way
Explanation: On August 15, this perseid meteor streaked through night skies over the Observatorio del Roque de los Muchachos at La Palma, Canary Islands, Spain. The bright and colorful meteor trail was captured next to the central Milky Way, whose dark interstellar dust clouds and luminous starlight reach above the horizon. In the foreground of this tantalizing celestial scene is the 23 meter diameter mirror of the prototype Large-Sized Telescope (LST-1). LST-1 is the first telescope constructed at the northern hemisphere site of the innovative Cherenkov Telescope Array Observatory. With 198 hexagonal mirror segments and a large, high-efficiency, pixelized camera, LST-1 is designed to detect extremely brief, atmospheric visible light flashes. Lasting about a billionth of a second, the visible light flashes are triggered by energetic gamma-rays from cosmic sources such as distant active galaxies and gamma-ray bursts. Of course, on that night some individual mirror segments of LST-1 also reflected the atmospheric flash of the bright perseid meteor.
APOD’s email for image submissions has changed. Please see: APOD Submissions.
APOD’s main NASA site is moving: From apod.nasa.gov to science.nasa.gov/apod
Tomorrow’s picture: before and after
| Date | September 26, 2026 |
|---|---|
| Credit & Copyright: | Jeff Dai (TWAN) |
| Authors & editors: | Jerry Bonnell, Cecilia Chirenti, Robert Nemiroff, Keighley Rockcliffe |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |
Source: science.nasa.gov
NASA, Boeing to Provide Update on Starliner Development
Boeing’s Starliner spacecraft that launched NASA’s Crew Flight Test astronauts Butch Wilmore and Suni Williams to the International Space Station is pictured docked to the Harmony module’s forward port.
Credit: NASA
During a news conference at 3 p.m. EDT on Monday, Sept. 28, NASA and Boeing leadership will discuss Starliner’s development and plans for regular crew flights to and from the International Space Station.
Learn where to watch online:
The briefing participants include:
- NASA Administrator Jared Isaacman
- Dana Weigel, manager, NASA’s Low Earth Orbit Program
- Woody Hoburg, NASA astronaut
- John Mulholland, vice president and program manager, Boeing Commercial Crew
Media already credentialed for Crew-13 may participate in person at NASA’s Kennedy Space Center in Florida. To ask questions, media must request the dial-in number from the Kennedy newsroom by emailing: [email protected] no later than one hour prior to the start of the call. A copy of NASA’s media accreditation policy is online.
For NASA’s blog and more information about the agency’s missions, visit:
-end-
George Alderman / Joshua Finch
Headquarters, Washington
202-358-1600
[email protected] / [email protected]
Source: www.nasa.gov
Air Force Reservist Leads Joint Team During NATO Pentathlon in Romania
An Air Force Reservist helped lead a joint three-member U.S. military team to a third-place finish in the novice division at the 2026 International Confederation of Reserve Officers Military Competition in Bucharest, Romania.
Source: www.war.gov
NASA Welcomes Côte d’Ivoire as Newest Artemis Accords Signatory
Credit: NASA
Côte d’Ivoire signed the Artemis Accords on Thursday, becoming the 75th signatory and marking a major milestone for this growing coalition. With the signing ceremony in the nation’s largest city, Abidjan, Côte d’Ivoire joined other like-minded nations and committed to the peaceful, transparent, and responsible exploration of the Moon, Mars, and beyond.
“The United States and Côte d’Ivoire already cooperate on Earth,” said NASA’s Deputy Administrator Matt Anderson. “Today, we expand that partnership beyond it. Joining the Artemis Accords opens new opportunities for our scientists, engineers, and institutions to work together as humanity returns to the Moon and prepares for what comes next. We’ve aligned on the principles. The opportunities are in front of us. And now we can get to work.”
The nation’s Minister of Higher Education and Scientific Research Adama Diawara signed on behalf of the country in a ceremony held during Africa Space Expo ASPEX 2026. Chargé d’affaires Junaid Munir from the U.S. Department of State witnessed the ceremony.
“This is a great achievement, and important for Côte d’Ivoire’s ambitions and for the rest of the African Union members,” said Director General of the Space Agency of Côte d’Ivoire Tidiane Outtara.
Côte d’Ivoire has expanded its involvement in space science and technology through years of international cooperation. Since 2019, the National Office of Technical Development of Côte d’Ivoire and NASA have collaborated on Earth observation and geodesy, a field that measures Earth’s shape, gravity, and movement. Together, the partners have advanced global geodetic networks, improved space‑based measurement techniques, and increased understanding of how Earth’s systems interact.
The country later established the Space Agency of Côte d’Ivoire in 2025 to coordinate national efforts in Earth observation, space weather, astronomy, satellite navigation, and communications.
In 2020, NASA and the State Department joined with seven other founding nations to establish the Artemis Accords, responding to the growing interest in lunar activities by both governments and private companies. The Artemis Accords are the first set of practical principles aimed at enhancing transparency, safety, and coordination among nations as they explore the Moon, Mars, and beyond, committing nations to:
- Explore peaceably and transparently
- Render aid to those in need
- Enable access to scientific data
- Ensure activities do not interfere with those of others
- Preserve historically significant sites and artifacts by developing best practices
By signing the Artemis Accords, nations open the door to opportunities for future lunar exploration with NASA, advancing humanity’s return to the Moon, and shaping the Golden Age of exploration and innovation.
Learn more about the Artemis Accords at:
https://www.nasa.gov/artemis-accords
Source: www.nasa.gov
Explosive Intensification for Hurricane Polo
modis
mur sst
NASA Earth Observatory/Michala Garrison
NASA Earth Observatory/Michala Garrison
NASA Earth Observatory/Michala Garrison
NASA Earth Observatory/Michala Garrison
modis
mur sst
After rapidly intensifying, Hurricane Polo spins off Mexico’s Pacific coast on September 23, 2026 (left), over unusually warm waters (right). NASA Earth Observatory images by Michala Garrison, using data from the MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Aqua satellite and the MUR SST (Multiscale Ultrahigh Resolution Sea Surface Temperature) project.
In mid-September 2026, Hurricane Polo began as a tropical disturbance off the Pacific coast of Mexico. By September 20, it was organized enough to qualify as a tropical depression, and by the next day it was a tropical storm.
From there, Polo launched into a period of rapid intensification that left meteorologists searching for adjectives strong enough to convey what was happening. Some described the storm’s rate of intensification and strength as “jaw-dropping,” others as “astonishing,” and others as “absolute insanity.”
“Polo went through a period of what can only be described as explosively rapid intensification,” said Gary Partyka, an atmospheric scientist with the Global Modeling and Assimilation Office (GMAO) at NASA’s Goddard Space Flight Center, in an email. “This was RAPID, rapid intensification.”
The storm was in an environment that was “near perfect” for strengthening, Partyka said, characterized by weak wind shear, high moisture, warmer ocean temperatures, and high levels of atmospheric instability.
Several observers leaned on extreme rapid intensification—a technical classification meaning the storm’s wind speeds increased at least 60 knots (111 kilometers or 69 miles per hour) within a 24-hour period. By September 22, the storm’s maximum sustained wind speed had risen by 90 knots (167 kilometers per hour or 104 miles per hour) within 24 hours, hitting category 5 strength. In its normally staid forecast discussions, the National Hurricane Center called the intensification “truly remarkable.”
When NOAA’s Hurricane Hunter aircraft flew over the storm on September 22, researchers estimated winds of nearly 285 kilometers (180 miles) per hour. That would make it the third-strongest storm on record in the eastern Pacific by maximum sustained winds and the fastest on record to go from a tropical depression to a category 5 storm, according to some analysts.
On the afternoon of September 23, when the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured this image (left), Polo was churning off the coast of Guerrero, southwest of Acapulco. With maximum sustained winds of 230 kilometers (145 miles) per hour, the storm was category 4 strength when the image was acquired, having undergone an eyewall replacement cycle that weakened it slightly.
“The satellite imagery of Polo is very impressive, with the storm’s large, clear eye and extensive outflow pattern,” said Kristen Corbosiero, an atmospheric scientist at the State University of New York at Albany, who is working on a NASA project that uses satellite data to study tropical cyclone ventilation. “Weak winds above the system and good outflow at the top of the system also contributed to Polo’s rapid intensification.”
As Polo developed, it moved over areas where sea surface temperatures were as high as 32 degrees Celsius (90 degrees Fahrenheit)—2 to 3 degrees warmer than usual for September 23. Surface waters across much of the region were above 27.8°C (82°F), the temperature generally required to sustain and intensify hurricanes.
The map above (right) is based on data from the Multiscale Ultrahigh Resolution Sea Surface Temperature (MUR SST) project at NASA’s Jet Propulsion Laboratory, which blends satellite measurements from NASA, NOAA, and international missions with observations from ships and buoys. Rather than absolute temperatures, the map shows anomalies—how much warmer or cooler the ocean surface was on September 23, 2026, than the project’s 2003-2014 average for that date.
While the map above conveys temperatures at the water surface, the presence of warm water deeper in the column has likely contributed to the storm’s staying power, Corbosiero added. Sometimes hurricanes churn up cooler water from deep in the column that can slow a storm’s intensification, but in this case the cool water wake behind the storm appears minimal, and measurements and models show high ocean heat content at considerable depths.
Both Partyka and Corbosiero cautioned against attributing Polo’s rapid intensification directly to El Niño’s unusually warm surface temperatures in the central and eastern Pacific Ocean. Several hurricanes in this region have undergone rapid intensification in the past during La Niña and neutral conditions, Corbosiero noted, including Hurricane Otis in 2023 and Patricia in 2015, both category 5 storms.
However, the overall amount of tropical cyclone activity in the eastern Pacific does typically increase during El Niño due to changes in large-scale ocean and atmospheric circulation patterns, and that’s what has happened so far in 2026. As of September 24, the accumulated cyclone energy in the region was nearly twice the norm, according to data from Colorado State University.
People tracking sea surface temperature anomalies or other aspects of the storm can do so using NASA’s Worldview browser, a near real-time data viewer from the Short-term Prediction Research and Transition (SPoRT) project, and the FLUID tool from GMAO. Forecasters expect Polo to stay over the Pacific until next week, when it may curve toward the northeast and approach Baja California.
NASA Earth Observatory images by Michala Garrison, using sea surface temperature data from the Multiscale Ultrahigh Resolution (MUR) project, MODIS data from NASA EOSDIS LANCE and GIBS/Worldview, and storm track data from NOAA’s National Hurricane Center. Story by Adam Voiland.
References & Resources
- Colorado State University (2026, September 23) Real-Time Northeast Pacific Ocean Statistics by Storm for 2026. Accessed September 24, 2026.
- Cooperative Institute for Research in the Atmosphere (2026) Polo. Accessed September 24, 2026.
- Eye on the Tropics (2026, September 23) Polo Puts on a Show Over the Eastern Pacific. Accessed September 24, 2026.
- Forbes (2026, September 22) Explosive Hurricane Polo Could Remain Category 5 For Days. Accessed September 24, 2026.
- Meir, J., via X (2026, September 24) Hurricane Polo is looking massive from the @Space_Station cupola. Accessed September 24, 2026.
- NASA Earthdata Tropical Cyclones. Accessed September 24, 2026.
- National Hurricane Center (2026) Hurricane POLO Advisory Archive. Accessed September 24, 2026.
- Stern, D., et al. (2026) Distinguishing Tropical Cyclone Extreme Rapid Intensification from Ordinary Rapid Intensification. Monthly Weather Review, 154(10), 2133-2149.
- The Washington Post (2026, September 22) Hurricane Polo intensified to a Category 5 in less than a day. Accessed September 24, 2026.
- Yale Climate Connections (2026, September 23) Powerful Hurricane Polo threatens Mexico with torrential rain as Pacific tropics erupt. Accessed September 24, 2026.
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APOD: 2026 September 25 – Globular Star Cluster Omega Centauri
APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Globular Cluster Omega Centauri
Explanation: Globular star cluster Omega Centauri packs about 10 million stars much older than the Sun into a volume some 150 light-years in diameter. Also known as NGC 5139, at a distance of 15,000 light-years it’s the largest and brightest of 200 or so known globular clusters that roam the halo of our Milky Way galaxy. Though most star clusters consist of stars with the same age and composition, the enigmatic Omega Cen exhibits the presence of different stellar populations with a spread of ages and chemical abundances. In fact, Omega Cen may be the remnant core of a small galaxy merging with the Milky Way. With a yellowish hue, Omega Centauri’s red giant stars are easy to pick out in this sharp telescopic view. A two-decade-long exploration of the dense star cluster with the Hubble Space Telescope has revealed evidence for a massive black hole near the center of Omega Centauri.
APOD’s email for image submissions has changed. Please see: APOD Submissions.
APOD’s main NASA site is moving: From apod.nasa.gov to science.nasa.gov/apod
Tomorrow’s picture: reflections on a starry night
| Date | September 25, 2026 |
|---|---|
| Credit & Copyright: | Javier O. Cadenas Parra |
| Authors & editors: | Jerry Bonnell, Cecilia Chirenti, Robert Nemiroff, Keighley Rockcliffe |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |
Source: science.nasa.gov
TB 26-07 Aluminum Alloy 2219 Material Guidance
For more information, contact Donald S. Parker, Kennedy Space Center, [email protected]
Improper casting and forging processes in the manufacture of aluminum alloy 2219 can lead to microstructural defects that result in a sub-optimal response to anodic surface treatments and an increase in corrosion susceptibility. This Technical Bulletin communicates the risks of improper casting and recommends a homogenizing step followed by multidirectional deformation after conventional direct chill casting, especially for larger castings. 09/24/26 DOC ID: 20260008373
Background
Aluminum 2219 is an age-hardenable, over-saturated, aluminum-copper alloy developed by Aluminum Company of America (Alcoa) in 1954, for service up to 600 °F. Numerous aerospace applications include launch and space vehicles including space shuttle fuel tanks, and International Space Station human-rated pressurized modules. It has excellent cryogenic properties, weldability, workability, and mechanical properties at low and high temperatures [1].
Problem/Issue Description
Casting 2219 aluminum alloy ingots is a specialized process used to manufacture large-scale structures that are subsequently forged or rolled into final product forms. The as-cast ingot internal defects may include disparate grain sizes, macrosegregation of alloying elements, and residual banded and clustered copper-rich intermetallics, which can lead to unsatisfactory mechanical and corrosion properties including low ductility, low strength, and a non-uniform distribution of material properties in the final product form. [2,11,12]
These defects can be somewhat mitigated with post-casting processes, including mechanical deformation, solution treatment, quenching, and aging. However, if ingots already possess unrecoverable discontinuities such as interdendritic segregation, banded and clustered large copper intermetallics, and disparate grain sizes, no subsequent thermos-mechanical processing will remedy the deficiencies in properties, especially for larger ingot sizes.
Homogenization as an Essential Step
Homogenization after casting greatly improves the final properties’ subsequent mechanical processing. Studies show that Fick’s laws of diffusion drive the highly concentrated copper atoms out of the interdendritic boundary zones, distributing them evenly across the aluminum matrix grains; residual phases are dissolved into the matrix, and degree of segregation of all elements reduces dramatically. Homogenization processing parameters need to be optimized for ingot cross-section thickness to ensure proper and uniform thermal response. Wang et al., who focused on homogenization, effectively used a temperature and time of 535 °C for 10 hours [3].
Homogenization optimization variables include the melting point, amount and dissolution rate of the eutectic phase, ingot size, grain size and copper content. Several researchers demonstrated that tools such as X-ray Diffraction (XRD) or Differential Scanning Calorimetry (DSC) are valuable tools for defining and verifying the homogenization step [3,4,5,6,7,8,9]. Improvement of microstructure and mechanical properties of homogenized aluminum 2219 is well documented. Scanning Electron Microscope (SEM) images from a study examining aluminum 2219 with varying amounts of copper show change in the morphology of grain boundaries after homogenizing in Figure 1.
The table below lists the results of Wang et al. who examined nonhomogenized and homogenized 2219, which were forged and treated to the T6 temper. The homogenized 2219 is clearly superior [3].
Thermomechanical Deformation Mechanical deformation such as forging — specifically, upset forging — and rolling, followed by solution treatment and aging, have been shown to drastically improve the aluminum 2219 microstructure by creating well distributed smaller-sized Al2Cu particles and significantly smaller grains leading to improved and less anisotropic mechanical properties. In one example of many studies, superior mechanical and microstructural properties were developed with a higher temperature multidirectional forging at 510 °C followed by warm rolling at 240 °C.
The upset forging and rolling followed by solution treatment and aging led to significantly reduced area fraction of coarse Al2Cu particles (5.5% to 1.0%) due to dissolution into the matrix. Grain size was reduced (230 micrometers to 58.6 micrometers) through increased storage energy and nucleation from the lower temperature rolling. Lastly, a uniformly distributed θ’ phase was increased by 118%. These changes in microstructure led to better strength, elongation and fracture properties[10].
Recommendation/Guidance
Homogenization after conventional direct chill casting is imperative to optimize the final properties of aluminum 2219 and should be explicitly included in procurement specifications. In addition, verification of effectiveness of the homogenization step is also recommended and could include before and after micrographs, DSC or XRD measurements. The initial micrographs are useful to verify a high-quality ingot. Multi-directional deformation is also important to aid fracturing of coarse particles, distribution of the Al2Cu and intermetallic phases, recrystallization, and nucleation of new grains leading to improved mechanical properties.
References
1. NASA-CR-74545
2. NASA-CR-123777
3. Wang et al., Materials 2018, 11, 914.
4. Chen et al., Metals 2020, 10, 197.
5. Zhang et al., Journal of Materials Research and Technology 2023, 27, 7470.
6. Gupta et al., Canadian Metallurgical Quarterly, 2006, 45, No. 3.
7. Xu et al., Metals 2021, 11, 174.
8. Zhang et al., Advanced Engineering Materials, 2024, 26.
9. Lin et al., Materials 2023, 16, 433.
10. Zhang et al., Journal of Materials Research and Technology 2023, 22, 1136.
11. NASA-TM-20230018439 12. NASA-TM-20240000329
Source: www.nasa.gov