This infrared image from NASA’s Spitzer Space telescope shows a cloud of gas and dust carved out by a massive star. A drawing overlaid on the image reveals why researchers nicknamed this region the “Jack-o’-lantern Nebula.” Credit: NASA/JPL-Caltech
Credits: NASA/JPL-Caltech
The Ghoul
Located within the constellation Perseus lies a star called Algol, also known as ‘Demon Star’ or ‘The Ghoul’. You can spot this star during the autumn months, along with Cassiopeia and Andromeda in the northeastern sky, beginning after 9 PM. In Greek mythology, this star represents the ‘blinking eye’ of the gorgon Medusa. But how can a star blink?
Light curve of the eclipsing binary star Algol recorded by NASA’s Transiting Exoplanet Survey Satellite (TESS), stored on NASA’s Mikulski Archive for Space Telescopes (MAST).
NASA/Wikipedia Commons
Algol is a triple-star system, with two of the three stars orbiting one another. This eclipsing binary causes the system to go from a bright +2.1 magnitude to a slightly dimmer +3.4 magnitude about every three days. Using data from NASA’s Transiting Exoplanet Survey Satellite (TESS) mission, this light curve shows the regular dimming, or Medusa’s ‘blinking eye’!
Using the constellations Cassiopeia and Andromeda, locate Perseus. You can find Algol by using the star Almach as a guide.
Stellarium
There is no shortage of resources on how to calculate the dimming – or minima – of Algol, from interactive charts to data plots. Find the one that works best for you. Because it has a similar magnitude of brightness, you can compare Algol’s brightness to the nearby star Almach (Gamma Andromedae) in Andromeda using a small telescope or binoculars.
Witch Head Nebula
Between the Eridanus and Orion constellations lies a spooky silhouette, illuminated by the star Rigel. IC 2118, or the Witch Head Nebula, is a reflection nebula about 900 light-years away from Earth. Because reflection nebulae rely on nearby starlight to appear visible, they can be difficult to see with the naked eye, especially if they are as far away as this one. While the Witch Head Nebula can’t be seen with the naked eye, telescopes with very large apertures and low magnification make it easier to catch under dark skies. Astrophotographers, with or without smart telescopes, can image this haunting outline within a few hours, depending on equipment and sky quality. And what is a witch without their broom! You can find the Witch’s Broom in the Western Veil Nebula, located in the constellation Cygnus.
An infrared portrait of the Witch Head nebula from NASA’s Wide-field Infrared Survey Explorer, or WISE, shows billowy clouds where new stars are brewing.
NASA/JPL-Caltech
Want more tips for getting into the season? Read our article on how you can make some spooky sidewalk astronomy fun for your community with Trick or Treat: Sidewalk Astronomy!
On Sept. 30, 1946, five National Advisory Committee of Aeronautics (NACA) engineers arrived at Muroc Army Airfield in California’s high desert to achieve supersonic flight for the first time. In less than two years, NACA flew the X-1 aircraft faster than the speed of sound, marking an important milestone in aviation history.
Fast forward 80 years, and that former NACA outpost is now NASA’s Armstrong Flight Research Center in Edwards, California, flying the X-59 supersonic X-plane in the same skies to demonstrate that supersonic flight doesn’t have to come with a boom.
Over Armstrong’s 80-year history, the center has supported milestone missions ranging from space shuttle landings to SR-71 flights, shaping the evolution of science, aeronautics, and space research.
This Southern California NASA center is poised to lead the next era of aeronautics and human spaceflight, advancing technologies that will define the future of flight.
Fast facts
NASA Administrator Jared Isaacman recently named Armstrong as the agency’s Center of Excellence for Flight Test and Aircraft Operations, recognizing the center’s unmatched rigor in executing unique missions only NASA can fly.
To support NASA’s Artemis missions and return to the Moon, Armstrong uses research aircraft such as a 737 for astronaut suit testing, the G-III for Artemis II heat-shield data collection, and an F/A-18 aircraft that tested the autopilot for the SLS (Space Launch System) rocket.
NASA’s aeronautics centerpiece, the X-59, is undergoing rigorous testing and a series of flights at Armstrong to prepare for upcoming quiet supersonic demonstrations over U.S. communities.
NASA Armstrong has transformed commercial and military aviation — from early supersonic flight research to digital fly-by-wire — and continues working with other government agencies, industry, and academia to make flying safer, more autonomous, and more efficient.
The center plays a vital role in global science by flying aircraft like the ER-2, C-20A, and Gulfstream G-III/IV/V to collect critical data on wildfires, glacier melt, pollution, minerals, and more.
Behind these achievements are the engineers, pilots, technicians, and mission support teams who continue to push the boundaries of what’s possible.
NASA Highlights Lessons Learned From Swift Boost Mission
A commercial mission to boost NASA’s Neil Gehrels Swift Observatory concluded without raising the spacecraft’s orbit, but the agency and industry vendor Katalyst Space have gained valuable experience that will benefit future in-space servicing programs.
“From the beginning, this was a high-risk, high-reward mission,” said Shawn Domagal-Goldman, Astrophysics Division director at NASA Headquarters in Washington. “Without intervention, Swift was going to re-enter the atmosphere by year’s end. And while we’ll be sad to see Swift’s mission come to a close, we knew this boost effort would be valuable to the agency on multiple levels — advancing U.S. spacecraft servicing technology, challenging us to meet unprecedented mission timelines, and testing how we operate satellites to extend their time in low Earth orbit. We’re very proud of how quickly this team got so far, and we’re capturing lessons learned to ensure we’re ready to go even farther.”
NASA’s Neil Gehrels Swift Observatory orbits above Earth in this artist’s concept.
NASA’s Goddard Space Flight Center Conceptual Image Lab
Swift, which launched in November 2004, was designed to study gamma-ray bursts, the most powerful explosions in the cosmos.
Over the last two decades, the observatory has revolutionized our understanding of how the universe works, from studying comets and asteroids in our own solar system and various types of cosmic explosions to flares from black holes in distant galaxies.
All spacecraft in low Earth orbit experience drag from our planet’s atmosphere. If they don’t have propulsion systems, this drag gradually reduces their altitudes. A period of increased solar activity magnified this effect on Swift.
In September 2025, NASA contracted Katalyst, based in Flagstaff, Arizona, to attempt the mission. The company had around one year to design, build, test, and launch a satellite that would then meet, grab, and lift Swift.
Katalyst Space’s LINK robotic servicing spacecraft awaits encapsulation inside a Northrop Grumman Pegasus XL rocket on June 8, 2026, at NASA’s Wallops Flight Facility in Virginia.
NASA/Ron Beard
The LINK spacecraft took off from Kwajalein Atoll in the Republic of the Marshall Islands in July aboard a Northrop Grumman Pegasus XL rocket. Katalyst selected the Pegasus as the best launch option for reaching the observatory on the mission’s condensed timeline, based on the mission’s orbital and programmatic needs.
After successfully reaching space and performing initial spacecraft checkouts, LINK began experiencing intermittent communications losses and developed issues with its orientation control.
Following a period of around-the-clock troubleshooting from both teams, NASA and Katalyst agreed to scale back the mission. LINK would no longer attempt to grab or boost Swift but instead attempt to perform a series of technology demonstrations that would advance the capabilities of the U.S. commercial servicing industry.
These included exercising the spacecraft’s xenon-powered propulsion system and three robotic arms, which were designed to provide flexibility regarding where LINK could safely grapple Swift. NASA formally concluded the agency’s involvement in LINK’s mission on Sept. 3. The spacecraft re-entered the atmosphere on Sept. 25.
“LINK was built to take on a problem that did not have an easy solution,” said Ghonhee Lee, CEO of Katalyst Space. “This was an ambitious mission on an aggressive timeline. While we did not accomplish every objective we set out to achieve, in less than a year we went from mission concept to launching and operating the first commercial space robot. This is a foundation we can build on.”
NASA’s Neil Gehrels Swift Observatory is seen as a streak in this image captured by Katalyst Space’s LINK spacecraft as it passed between 7.5 and 9 miles (12 to 15 kilometers) of Swift
Katalyst Space
Science missions like Swift take years to develop and then operate in orbit for decades. For the Swift boost, however, the most important factor was the timeline. All decision-making and risk acceptance hinged on predictions showing the observatory sinking to the point of no return — an altitude of around 185 miles (300 kilometers) — in fall 2026. As such, the boost mission required a new form of agile project management for NASA.
Swift team members in SSMO (Space Science Mission Operations) at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, worked with Katalyst to develop milestones and approval processes that gave the mission the best chance of success while being flexible enough to move quickly toward launch.
Both groups received valuable input and feedback from NASA’s Engineering and Safety Center when tackling questions and issues that arose during integration and testing.
“Katalyst was committed to leveraging NASA’s deep experience to give themselves the best possible chance of successfully achieving the unprecedented challenge we gave them,” said Russell Carpenter, project manager in SSMO at NASA Goddard “Missions like these, where public-private teams work tenaciously to overcome obstacles, are an inspiration to the world, reminding us that striving for the near impossible brings out what is exceptional in all of us.”
Katalyst engineers attach LINK to a baseplate inside the Space Environment Simulator at NASA’s Goddard Space Flight Center in Greenbelt, Md., on April 28, 2026. Once all the air was pumped out of the 27-foot-diameter chamber, the team practiced firing the satellite’s ion thrusters and operated one of the robotic arms while they cycled through space-like hot and cold temperatures.
NASA/Sophia Roberts
While teams at NASA and Katalyst were racing to get LINK ready on the ground, flight controllers in Swift’s Mission Operations Center, located at Penn State in University Park in Pennsylvania, were trying to keep Swift above the critical altitude for as long as possible. Below it, any boost attempt would become increasingly difficult.
During normal operations, the Penn State team sends a plan to Swift that tells the observatory which cosmic objects and events to observe each day.
In December 2025, however, the controllers started swapping around 25% of these science targets for points on the sky that would minimize drag when Swift was trained on them. By February, the team had switched over to this approach entirely.
“Even though Swift was not executing pointed science observations from mid-February to late August, we nonetheless continued Penn State’s history of innovative space research and operations, pioneering new methods to minimize drag experienced by the spacecraft,” said John Nousek, the mission director and professor of astronomy and astrophysics in the university’s Eberly College of Science. “These changes bought valuable time for the boost mission and can be carried forward for future NASA missions.”
The team also couldn’t point too close to Earth, the Moon, or the Sun, since the brightness of all three could overheat and damage the observatory’s instruments. Pointing Swift in the most streamlined position also tilted it too close to the atmosphere, where particles could collide with the telescopes and affect future observations. The team struck a balance that managed to maintain Swift’s altitude above the critical threshold for several months.
“We’re grateful to all our collaborators for the incredible amount of time and dedication they’ve put into the boost mission,” said S. Bradley Cenko, Swift’s principal investigator at NASA Goddard. “When Neil Gehrels, Swift’s namesake, designed the observatory, nothing like it had ever launched. He would have celebrated that this boost effort was part of Swift’s legacy, that it allowed NASA to try something new and daring even though the outcome wasn’t guaranteed. That’s how we explore the universe — as a team, learning from each other, constantly pushing forward.”
Jeanette Kazmierczak is a science writer at the University of Maryland, College Park and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, where she covers missions and research in the Astrophysics Science Division.
Kristie Foster, quality engineer at NASA’s Stennis Space Center near Bay St. Louis, Mississippi, poses for a photograph inside the High Pressure Industrial Water Facility on Sept. 10, 2026. Foster is now a NASA civil servant at Stennis as part of the administrator’s directive to strengthen technical core competencies within the civil service workforce.
NASA/Danny Nowlin
Kristie Foster paved her road to becoming a NASA civil servant with literal miles of dedication. Her work at the agency’s Stennis Space Center near Bay St. Louis, Mississippi, supports NASA’s mission to return American astronauts to the Moon, build a Moon Base for an enduring presence on the lunar surface, and ensure American leadership in space.
Foster’s move from a long-time contractor to a civil servant secures critical institutional knowledge after being hired in June under the agency’s workforce directive to restore core competencies.
“It means a lot, especially carrying the family legacy forward after my father retired from NASA last year after working about 20 years at Stennis,” said Foster. “It meant something to finally see that dream come true in full circle.”
As a quality engineer, Foster manages quality assurance and engineering at America’s largest rocket propulsion test site with much of her focus at the High Pressure Gas Facility and High Pressure Industrial Water Facility.
Known as the heart of Stennis, the gas facility is where gaseous nitrogen, helium, hydrogen, and air are created, stored, and distributed through a 7-mile pipeline across the center for propulsion testing. The water facility utilizes a 66-million-gallon reservoir to pump massive volumes of water to the test stands for cooling and sound suppression.
She also has taken on a safety role of supporting the build up at the Thad Cochran Test Stand (B-2), where Blue Origin will conduct second stage hot fire testing of the company’s New Glenn rocket.
Her technical work involves reviewing test preparation sheets, verifying operational plans in the field, and ensuring processes are executed from the initial design phase through final closeout.
“If you put safety and quality up front and incorporate it throughout the entire process, you are going to end up with a better product at the end,” said Foster. “Because NASA pushes safety and actively performs it, we are able to work at a fast pace with safety at the forefront.”
Foster applies an adaptable, mission-first mindset to her work that is advancing Artemis missions. Following the successful Artemis II mission last April, Artemis III is intended to demonstrate integrated operations between the Orion spacecraft and test versions of commercial human landing systems before Artemis IV returns astronauts to the lunar surface.
“I feel like the space race is back to that original excitement all over again,” said Foster. “Artemis I and II were huge, successful missions. That was amazing to be a part of, and it is something to look forward to with Artemis III and IV. I want to see humans back on the Moon. It is exciting.”
While her focus is now on returning humans to the Moon, Foster’s own journey to NASA started close to home. She completed two years at Pearl River Community College, along with summer night classes at Mississippi Gulf Coast Community College.
Her first time working at Stennis came with the largest tenant of the NASA Stennis Federal City: The United States Navy, and an internship with the Naval Oceanographic Office.
While finishing her bachelor’s degree in construction management and land development at Mississippi State University, Foster landed a four-week holiday internship on a Stennis construction project. This evolved into a senior-year schedule of working three days a week at Stennis, then driving hours back to campus to attend classes the other four days.
The hard work paid off with a full-time job. Foster worked as a contractor supporting NASA’s work from 2008 until her recent hire with the agency.
A resident of Poplarville, Mississippi, Foster balances her career with life on a farm. Her 12-year-old son, an avid space enthusiast, now shares similar aerospace conversations with his mother that she once had with her father.
As Foster ensures the safety and quality of NASA’s propulsion testing at Stennis, she is leading by example for her son and the Artemis Generation.
“I have always lived by the saying: ‘Shoot for the Moon, because even if you miss, you land among the stars.’ That is how I have approached my career,” said Foster. “It takes persistence and enjoying what you do. One neat thing about working with NASA at Stennis, especially in the test complex, is that I have never done the same thing twice. It is always an evolving situation.”
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.
Cosmic Latte: The Average Color of the Universe
Explanation: What color is the universe? More precisely, if the entire sky were smeared out, what color would the final mix be? This whimsical question came up when trying to determine what stars are commonplace in nearby galaxies. The answer, depicted here, is a conditionally perceived shade of beige. In computer parlance: #FFF8E7. To determine this, astronomers computationally averaged the light emitted by one of the larger samples of galaxies analyzed: the 200,000 galaxies of the 2dF Galaxy Redshift Survey. The resulting cosmic spectrum has some emission in all parts of the electromagnetic spectrum, but a single perceived composite color. This color has become much less blue over the past 10 billion years, indicating that redder stars are becoming more prevalent. In a contest to better name the color, notable entries included skyvory, univeige, and the winner: cosmic latte.
Dexterous Robotics Team lead Shaun Azimi conducts a demonstration with NASA’s Valkyrie humanoid robot.
NASA
The idea of humans and robots working side-by-side in space was once the stuff of science fiction, but with NASA launching increasingly complex missions deeper into space, human-robot collaboration could become reality.
Advanced robotic systems are critical for human spaceflight because they can enhance a crew’s performance and productivity while reducing risk and expanding the capabilities for space exploration. The Dexterous Robotics Team at NASA’s Johnson Space Center in Houston plays a key role in developing robotic hardware and software to support NASA’s bold vision for the future, with a focus on robots that can complete tasks humans do with their hands.
“Our team is not trying to replace human explorers with robots but instead make human exploration safer and more sustainable by developing highly capable, reliable, and trustworthy robots to work in extreme environments,” said Shaun Azimi, Dexterous Robotics Team lead. “If we can send more capable robots, we can reduce the risk and make people more effective in doing the things that people do best.”
Dexterous Robotics Team members Nathan Dunkelberger (left) and Connor Rainen test the use of a robotic arm.
NASA
The 16-member team is part of NASA’s Robotic System Technology Branch, which also develops mobility systems like unmanned planetary rovers. Azimi is one of several engineers who work on both dexterity and mobility projects. There is also crossover within the Dexterous Robotics Team. While the group is generally organized into two subgroups, mechatronics and software, most team members have experience in electronics or mechanics as well as writing software for simulations or analyses.
Much of that experience was gained by working on two well-known humanoid robots – the Robonaut 2, which participated in robotics technology demonstrations aboard the International Space Station for seven years, and Valkyrie, NASA’s first bipedal humanoid robot. Many of the employees who worked on those projects now make up the Dexterous Robotics Team and continue to build upon the robots’ legacy.
NASA’s Robonaut 2 (left) and Valkyrie humanoid robots.
NASA
Today the team supports a variety of agency projects and programs, some of which are exploring connections to building the Moon Base, humanity’s first lunar outpost. “Our work is a combination of technology research and development, and applied technology on the operational side,” Azimi said. The team also collaborates with private industry and other external partners that face similar challenges in their work, such as an oil and gas company seeking to leverage robotic technologies in harsh environments and for riskier tasks.
During a demonstration, Valkyrie hands Dexterous Robotics Team member Emily Sheetz a packed duffel bag.
NASA/Helen Arase Vargas
A major focus for the team has been development of the Integrated Mobile Evaluation Testbed for Robotics Operations (iMETRO) facility at Johnson. Available to NASA programs and external partners, iMETRO is designed to support the adaptation of terrestrial robotic technologies for human-supervised space exploration applications such as logistics, maintenance, and scientific research. The facility comprises open-source software and simulation assets, as well as space vehicle and habitat mockups, a selection of “house robots,” and an outdoor rock yard. Offering digital and physical facilities gives iMETRO users the flexibility to test a whole robot or a single hardware or software component.
Azimi said iMETRO helps remove the guesswork from NASA’s collaboration with external partners. “It shows them the things we actually need done so they don’t have to speculate,” he said. “We can also bring together the people who are developing the robotic technologies – hardware, software, or both – with the people who are actually designing a lunar surface habitat or rover.” This enables different teams to learn from each other: The technology providers gain a better understanding of the habitat, while the habitat designers learn what features are needed to accommodate a robot. “They can learn about how robots perceive the world and interact with objects, and what is difficult for a robot compared to a human,” Azimi said. “It’s not necessarily a totally different interface, and something like a bigger handle or better lighting might make things easier for a person as well.”
In one case, a team from PickNik Inc. used iMETRO to test software enabling a robotic arm to recognize a spacecraft hatch, then turn the latch, grasp the handle, and open the door. The arm was then able to transfer cargo bags between the hatch and a bin. The facility also supported a NASA intern’s development and testing of software that used a common commercial robotic arm and camera to inspect and maintain a cold stowage freezer like those aboard the space station.
Components of the Dexterous Robotics Team’s iMETRO facility.
NASA
Azimi acknowledged the team’s near-term emphasis on technologies that can support a sustained human presence on the lunar surface but noted those technologies also have applications for future missions to Mars. In fact, the team is collaborating with other agency organizations on a forthcoming NASA challenge that will invite the public to share their ideas for technology solutions for Mars exploration.
Azimi said he is often asked why there is a robotics team at Johnson. “It’s really about the human elements – either working in environments designed for humans or working alongside humans. That’s our niche,” he said. “We’re uniquely positioned to bring in folks who are designing the human environments.”
A newly developed method for mapping the bedrock beneath Greenland’s ice sheet reveals the island’s hidden topography. Among the most striking finds are long, straight valleys in the west-central region, some mapped for the first time and others extending farther inland than previously known (inset 3).
NASA Earth Observatory/Lauren Dauphin, based on data from Chartrand et al.
Greenland is capped with a vast ice sheet that spans 1.7 million square kilometers (656,000 square miles) and measures more than 3 kilometers (1.9 miles) at its thickest point. Below all this ice lies a landscape human eyes have never seen directly. But a newly developed method for mapping this hidden bedrock has produced the most detailed and accurate view of it yet.
The new map reveals an expansive network of valleys carved into the surface beneath the Greenland Ice Sheet. Many of the features formed well before most of the ice above them existed, offering new context for the island’s geologic history—and potentially helping scientists refine projections of the ice sheet’s future. Scientists described the newly mapped valleys in a NASA-led paper published in Geophysical Research Letters.
The map, shown above, was derived from a method called Ice Flow Perturbation Analysis. As ice flows over a valley or ridge, the topography leaves a faint signature on the ice surface. Satellites map the ice surface in fine detail, and scientists can use these subtle bumps and dips to infer the shape of the landscape buried below. The work aims to improve future versions of BedMachine Greenland, a high-resolution dataset of the terrain beneath the ice sheet.
Using the technique, researchers manually mapped 1,943 subglacial valleys beneath the Greenland Ice Sheet, about a third of which are newly identified. About half of the valleys included in BedMachine Greenland, primarily near the ice sheet’s edge, are now known to extend farther inland than that map indicates, in some cases by hundreds of kilometers.
Some aspects of the new map align with the current understanding of how Greenland’s landscapes formed. For instance, many of the valleys appear to begin in the southern and eastern highlands, where the ice sheet is thought to have first formed. Near the eastern highlands, the map reveals a mountain range beneath the ice, with interconnected valleys and relief that increases toward the coast. These alpine-style landforms may have survived under the ice since at least the Pliocene.
Other aspects of the topography are more puzzling. The analysis indicates numerous valleys, especially in the west-central region, that are long, straight, and consistently aligned in a southwest-northeast direction. This orientation suggests a tectonic influence, generating preferential pathways along which water could flow and valleys could form. “That’s a riddle to us,” said Joe MacGregor, a NASA cryospheric scientist and co-author of the study. “Greenland is justifiably usually treated as a rigid block of old rock that is simply translated as needed to accommodate the motion and interactions of other tectonic plates.”
Separately, the angles at which the valleys branch offer another insight into their origin. Their relatively wide branching angles suggest that surface water didn’t act alone; instead, a widespread groundwater network—seeping upward and eroding the surrounding rock—likely helped carve the valleys before the ice sheet formed.
Mapping these valleys matters for understanding the ice sheet, which has continued to dramatically reshape the landscape. Ice flow concentrates in valleys, where it forms glaciers that eventually calve into fjords at the periphery of the ice sheet. This creates a reinforcing cycle: ice funneling through a valley gets thicker, thicker ice flows faster, and faster flow carves the valley even deeper.
This carving power is especially evident along western Greenland. MacGregor likened it to the glacially incised landscape at Yosemite, with Greenland’s western coast resembling, as he put it, “El Capitan after El Capitan.”
Studying the valleys also matters for the ice sheet’s future. Because the relationship between ice flow and valleys is well understood, scientists expect that as the ice sheet retreats, flow will continue to concentrate wherever the valleys already are. “The better we understand the topography now,” MacGregor said, “the better sense we’ll have of what it will look like in the longer term—beyond the next decade or two—as faster ice flow propagates into Greenland’s interior.”
NASA Earth Observatory map by Lauren Dauphin using data from Chartrand et al. Story by Kathryn Hansen.
