Aero Engineer Brings NASA into Hawaii’s Classrooms

Aero Engineer Brings NASA into Hawaii’s Classrooms

Side-by-side photos of a teacher with a young student and the same teacher with the same student who has grown up.
On the left, NASA Ames engineer Evan Kawamura on his first day of sixth grade with teacher Kristen Stoker of Hanalani Schools. On the right, Kawamura reunited with Mrs. Stoker when speaking to her students about his work at NASA.

The field of aerial vehicle autonomy focuses on self-reliance, building the flight equivalent of puppets without puppeteers. Behind the scenes, however, is a rich network of people and systems that work together to develop frameworks, test new technologies, and inspire a pipeline of engineers to create the breakthroughs of the future. Encouraging kids to dream big and pursue their STEM passions is especially important to Evan Kawamura, a guidance, navigation and control engineer in the Intelligent Systems Division at NASA’s Ames Research Center in California’s Silicon Valley.

Kawamura takes mentorship and STEM outreach as seriously as his work in unmanned aerial vehicles (UAVs) and Advanced Air Mobility (AAM). He extends his duty as an engineer from his office to classrooms across Oahu, Hawaii, where he lives. He has led drone-building workshops, presented about his journey to NASA, and connected with hundreds of students and educators. Most recently, Kawamura returned to his alma mater and reunited with his sixth-grade teacher, Mrs. Kristen Stoker, to talk to her students about his work at NASA.

“Since my family, teachers, advisors, mentors, and professors provided me with wonderful opportunities and experiences that inspired and prepared me for engineering, I feel that it’s crucial to continue to inspire the next generation,” he said. “If we do not protect, inspire, and educate our children, then the future is dark and uncertain.”

Evan Kawamura, computer guidance, navigation, and control engineer, with two hexacopters in the NASA Unmanned Aircraft System Autonomy Research Complex.
Credit: NASA/Dominic Hart

Kawamura writes code that helps aerial vehicles launch, fly, and land without intervention from human operators. One of his early proud moments was in the summer of 2019 when, with the help of his team lead and mentor, Corey Ippolito of NASA Ames’ Airborne Science Program, he successfully programmed a six-propellered hexacopter to launch from and return to a defined point in space without a human driver.

“It was very rewarding and fulfilling to see our efforts pay off both in simulation and in a real world flight test,” Kawamura said. “The work also became the baseline autonomy code for others on our team and my graduate school research too, so I felt a lot of pressure during development but a huge relief when it worked.”

Kawamura comes from a long line of builders and engineers, back to his boatbuilding great-great- grandfather who moved to Hawaii from Japan in 1909 with his nine-year-old son. Evan’s father, a software engineer, bought him science and engineering books, and entertained endless questions about how things work. His grandfather, a contractor who built the house Evan’s dad grew up in, was a fan of origami and spent countless hours teaching Evan to fold boats and planes. His family inspired in him a fascination for the ways different materials could fit together like trains and LEGO to make something new, but sometimes he didn’t get to play with his creations.

“I got excited to create a battle with all the paper planes and boats my grandpa and I made,” Kawamura said. “But he fell asleep before we could start playing.”

The cool and strange thing is that I see the aloha spirit at NASA Ames, which was one of the main reasons that made me want to work at NASA.

Evan kawamura

Evan kawamura

NASA Engineer

Kawamura joined Ames as an intern while getting his PhD at University of Hawaii at Manoa. He completed his first internship in 2018, returned in the spring of 2019, and accepted a NASA Pathways internship later that summer. In 2021, Kawamura converted to a remote full-time employee at Ames. All along the way, he relied on the guidance and support of his family, mentors, and teammates. That experience drives him to pay forward the inspiration and encouragement that helped him get where he is today.

“Growing up in Hawaii fosters a ‘togetherness’ mindset that is very inclusive and family-oriented,” he said. “Helping others, sharing burdens, and having each other’s backs opens channels of communication to build friendships and foster collaboration, which is what aloha is all about. The cool and strange thing is that I see the aloha spirit at NASA Ames, which was one of the main reasons that made me want to work at NASA.”

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40 Years Ago: STS-9, the First Spacelab Science Mission

40 Years Ago: STS-9, the First Spacelab Science Mission

On Nov. 28, 1983, space shuttle Columbia took to the skies for its sixth trip into space on the first dedicated science mission using the Spacelab module provided by the European Space Agency (ESA). The longest shuttle mission at the time also included many other firsts. Aboard Columbia to conduct dozens of science experiments, the first six-person crew of Commander John W. Young, making his record-breaking sixth spaceflight, Pilot Brewster H. Shaw, Mission Specialists Owen K. Garriott and Robert A.R. Parker, and the first two payload specialists, American Byron K. Lichtenberg and German Ulf Merbold representing ESA, the first non-American to fly on a U.S. space mission. During the 10-day Spacelab 1 flight, the international team of astronauts conducted 72 experiments in a wide variety of science disciplines.

The STS-9 crew patch Official photo of the STS-9 crew of Owen K. Garriott, seated left, Brewster H. Shaw, John W. Young, and Robert A.R. Parker; Byron K. Lichtenberg, standing left, and Ulf Merbold of West Germany representing the European Space Agency The payload patch for Spacelab 1
Left: The STS-9 crew patch. Middle: Official photo of the STS-9 crew of Owen K. Garriott, seated left, Brewster H. Shaw, John W. Young, and Robert A.R. Parker; Byron K. Lichtenberg, standing left, and Ulf Merbold of West Germany representing the European Space Agency. Right: The payload patch for Spacelab 1.

In August 1973, NASA and the European Space Research Organization, the forerunner of today’s ESA, agreed on a cooperative plan to build a reusable laboratory called Spacelab to fly in the space shuttle’s cargo bay. In exchange for ESA building the pressurized modules and unpressurized pallets, NASA provided flight opportunities for European astronauts. In December 1977, ESA named physicist Merbold of the Max Planck Institute in West Germany, physicist Wubbo Ockels of The Netherlands, and astrophysicist Claude Nicollier of Switzerland as payload specialist candidates for the first Spacelab mission. In September 1982, ESA selected Merbold as the prime crew member to fly the mission and Ockels as his backup. Nicollier had in the meantime joined NASA’s astronaut class of 1980 as a mission specialist candidate. In 1978, NASA selected biomedical engineer Lichtenberg of the Massachusetts Institute of Technology as its payload specialist with physicist Michael L. Lampton of CalTech as his backup. In April 1982, NASA assigned the orbiter crew of Young, Shaw, Garriott, and Parker. As commander of STS-9, Young made a record-breaking sixth flight into space. The mission’s pilot Shaw, an astronaut from the 1978 class, made his first trip into space. The two mission specialists had a long history with NASA – Garriott, selected as an astronaut in 1965, completed a 59-day stay aboard the Skylab space station in 1973, and Parker, selected in 1967, made his first spaceflight after a 16-year wait. Although the crew included only two veterans, it had the most previous spaceflight experience of any crew up to that time – 84 days between Young’s and Garriott’s earlier missions.

Arrival of the Spacelab 1 long module at NASA’s Kennedy Space Center (KSC) in Florida Workers place the Spacelab module and pallet into Columbia’s payload bay in KSC’s Orbiter Processing Facility The Spacelab pallet, top, pressurized long module, and tunnel in Columbia’s payload bay
Left: Arrival of the Spacelab 1 long module at NASA’s Kennedy Space Center (KSC) in Florida. Middle: Workers place the Spacelab module and pallet into Columbia’s payload bay in KSC’s Orbiter Processing Facility. Right: The Spacelab pallet, top, pressurized long module, and tunnel in Columbia’s payload bay.

The pressurized module for the first Spacelab mission arrived at KSC on Dec. 11, 1981, from its manufacturing facility in Bremen, West Germany. Additional components arrived throughout 1982 as workers in KSC’s Operations and Checkout Building integrated the payload racks into the module. The ninth space shuttle mission saw the return of the orbiter Columbia to space, having flown the first five flights of the program. Since it arrived back at KSC after STS-5 on Nov. 22, 1982, engineers in the Orbiter Processing Facility (OPF) modified Columbia to prepare it for the first Spacelab mission. The completed payload, including the pressurized module, the external pallet, and the transfer tunnel, rolled over to the OPF, where workers installed it into Columbia’s payload bay on Aug. 16, 1983.

In the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida, workers lift space shuttle Columbia to mate it with its external tank (ET) and solid rocket boosters (SRBs) for the first time Space shuttle Columbia’s first trip from the VAB to Launch Pad 39A In the VAB, workers have disassembled the stack and prepare to reposition the ET with its SRBs
Left: In the Vehicle Assembly Building (VAB) at NASA’s Kennedy Space Center in Florida, workers lift space shuttle Columbia to mate it with its external tank (ET) and solid rocket boosters (SRBs) for the first time. Middle: Space shuttle Columbia’s first trip from the VAB to Launch Pad 39A. Right: In the VAB, workers have disassembled the stack and prepare to reposition the ET with its SRBs.

Rollover of Columbia to the Vehicle Assembly Building (VAB) took place on Sept. 24, where workers mated it with an external tank (ET) and two solid rocket boosters (SRBs). Following integrated testing, the stack rolled out to Launch Pad 39A four days later for a planned Oct. 29 liftoff. However, on Oct. 14, managers called off that initial launch attempt after discovering that the engine nozzle of the left hand SRB contained the same material that nearly caused a burn through during STS-8. The replacement of the nozzle required a rollback to the VAB. Taking place on Oct. 17, it marked the first rollback of a flight vehicle in the shuttle’s history. Workers in the VAB demated the vehicle and destacked the left hand SRB to replace its nozzle. Columbia temporarily returned to the OPF on Oct. 19, where workers replaced its fuel cells using three borrowed from space shuttle Discovery and also replaced its waste collection system. Columbia returned to the VAB on Nov. 3 for remating with its ET and SRBs and rolled back out to the launch pad on Nov. 8.

The STS-9 crew during their preflight press conference at NASA’s Johnson Space Center in Houston On launch day at NASA’s Kennedy Space Center in Florida, the STS-9 astronauts leave crew quarters to board the Astrovan for the ride to Launch Pad 39A In the VIP stands to watch the STS-9 launch, Steven Spielberg, left, and George Lucas
Left: The STS-9 crew during their preflight press conference at NASA’s Johnson Space Center in Houston. Middle: On launch day at NASA’s Kennedy Space Center in Florida, the STS-9 astronauts leave crew quarters to board the Astrovan for the ride to Launch Pad 39A. Right: In the VIP stands to watch the STS-9 launch, Steven Spielberg, left, and George Lucas.

-Liftoff of space shuttle Columbia on STS-9 carrying the first Spacelab science module
Liftoff of space shuttle Columbia on STS-9 carrying the first Spacelab science module.

Ground track of STS-9’s orbit, inclined 57 degrees to the equator, passing over 80 percent of the world’s land masses
Ground track of STS-9’s orbit, inclined 57 degrees to the equator, passing over 80 percent of the world’s land masses.

On Nov. 28, 1983, Columbia thundered off KSC’s Launch Pad 39A to begin the STS-9 mission. The shuttle entered an orbit inclined 57 degrees to the equator, the highest inclination U.S. spaceflight at the time, allowing the astronauts to observe about 80 percent of the Earth’s landmasses. Mounted inside Columbia’s payload bay, the first Spacelab 18-foot long module provided a shirt-sleeve environment for the astronauts to conduct scientific experiments in a variety of disciplines. During the Spacelab 1 mission, the STS-9 crew carried out 72 experiments in atmospheric and plasma physics, astronomy, solar physics, materials sciences, technology, astrobiology, and Earth observations. For the first time in spaceflight history, the crew divided into two teams working opposite 12-hour shifts, allowing science to be conducted 24 hours a day. The Tracking and Data Relay Satellite, launched the previous April during the STS-6 mission, and now fully operational, enabled transmission of television and significant amounts of science data to the Payload Operations Control Center, located in the Mission Control Center at NASA’s Johnson Space Center in Houston.

View of the Spacelab module in the shuttle’s payload bay Several STS-9 crew members struggle to open the hatch to the transfer tunnel Owen K. Garriott, left, Ulf Merbold, and Byron K. Lichtenberg enter the Spacelab for the first time to begin activating the module
Left: View of the Spacelab module in the shuttle’s payload bay. Middle: Several STS-9 crew members struggle to open the hatch to the transfer tunnel. Right: Owen K. Garriott, left, Ulf Merbold, and Byron K. Lichtenberg enter the Spacelab for the first time to begin activating the module.

Upon reaching orbit, the crew opened the payload bay doors and deployed the shuttle’s radiators. Shortly after, following a few tense minutes during which the astronauts struggled with a balky hatch, they opened it, translated down the transfer tunnel, and entered Spacelab for the first time. Garriott, Lichtenberg, and Merbold activated the module and turned on the first experiments. For the next nine days, the Red Team of Young, Parker, and Merbold, and the Blue Team of Shaw, Garriott, and Lichtenberg performed flawlessly to carry out the experiments. Young and Shaw managed the shuttle’s systems while the mission and payload specialists conducted the bulk of the research. With ample consumables available, Mission Control granted them an extra day in space to complete additional science. One afternoon, the astronauts chatted with U.S. President Ronald W. Reagan in the White House and German Chancellor Helmut Kohl, attending the European Community Summit in Athens, Greece. The two leaders praised the astronauts for their scientific work and the cooperation between the two countries that enabled the flight to take place.

Garriott preparing to draw a blood sample from Lichtenberg for one of the life sciences experiments Garriott, front, and Lichtenberg at work in the Spacelab module
Left: Robert A.R. Parker, left, Byron K. Lichtenberg, Owen K. Garriott, and Ulf Merbold at work inside the Spacelab module. Middle: Garriott preparing to draw a blood sample from Lichtenberg for one of the life sciences experiments. Right: Garriott, front, and Lichtenberg at work in the Spacelab module.

The rotating dome experiment to study visual vestibular interactions Owen K. Garriott prepares to place blood samples in a passive freezer Inflight photograph of the STS-9 crew
Left: The rotating dome experiment to study visual vestibular interactions. Middle: Owen K. Garriott prepares to place blood samples in a passive freezer. Right: Inflight photograph of the STS-9 crew.

The Manicougan impact crater in Quebec, Canada, with the shuttle’s tail visible at upper right STS-9 crew Earth observation photograph Hong Kong STS-9 crew Earth observation photograph of Cape Campbell, New Zealand
A selection of the STS-9 crew Earth observation photographs. Left: The Manicougan impact crater in Quebec, Canada, with the shuttle’s tail visible at upper right. Middle: Hong Kong. Right: Cape Campbell, New Zealand.

On Dec. 8, their last day in space, the crew finished the experiments, closed up the Spacelab module, and strapped themselves into their seats to prepare for their return to Earth. Five hours before the scheduled landing, during thruster firings one of Columbia’s five General Purpose Computers (GPC) failed, followed six minutes later by a second GPC. Mission Control decided to delay the landing until the crew could fix the problem. Young and Shaw  brought the second GPC back up but had no luck with the first. Meanwhile, one of Columbia’s Inertial Measurement Units, used for navigation, failed. Finally, after eight hours of troubleshooting, the astronauts fired the shuttle’s Orbital Maneuvering System engines to begin the descent from orbit. Young piloted Columbia to a smooth landing on a lakebed runway at Edwards Air Force Base in California’s Mojave Desert, completing 166 orbits around the Earth in 10 days, 6 hours, and 47 minutes, at the time the longest shuttle flight. Shortly before landing, a hydrazine leak caused two of the orbiter’s three Auxiliary Power Units (APU) to catch fire. The fire burned itself out, causing damage in the APU compartment but otherwise not affecting the landing. The astronauts safely exited the spacecraft without incident. On Dec. 14, NASA ferried Columbia back to KSC to remove the Spacelab module from the payload bay. In January 1984, Columbia returned to its manufacturer, Rockwell International in Palmdale, California, where workers spent the next two years refurbishing NASA’s first orbiter before its next mission, STS-61C, in January 1986.

John W. Young in the shuttle commander’s seat prior to entry and landing Space shuttle Columbia lands at Edward Air Force Base in California to end the STS-9 mission Space shuttle Columbia lands at Edward Air Force Base in California to end the STS-9 mission
Left: John W. Young in the shuttle commander’s seat prior to entry and landing. Middle: Space shuttle Columbia lands at Edward Air Force Base in California to end the STS-9 mission. Right: The six STS-9 crew members descend the stairs from the orbiter after their successful 10-day scientific mission.

Workers at Edwards Air Force Base in California safe space shuttle Columbia after its return from space Atop a Shuttle Carrier Aircraft, Columbia begins its cross country journey to NASA’s Kennedy Space Center in Florida The STS-9 crew during their postflight press conference at NASA’s Johnson Space Center in Houston
Left: Workers at Edwards Air Force Base in California safe space shuttle Columbia after its return from space. Middle: Atop a Shuttle Carrier Aircraft, Columbia begins its cross country journey to NASA’s Kennedy Space Center in Florida. Right: The STS-9 crew during their postflight press conference at NASA’s Johnson Space Center in Houston.

The journal Science published preliminary results from Spacelab 1 in their July 13, 1984, issue. The two Spacelab modules flew a total of 16 times, the last one during the STS-90 Neurolab mission in April 1998. The module that flew on STS-9 and eight other missions is displayed at the Stephen F. Udvar-Hazy Center of the Smithsonian Institution’s National Air and Space Museum in Chantilly, Virginia, while the other module resides at the Airbus Defence and Space plant in Bremen, Germany, not on public display.

The Spacelab long module that flew on STS-9 and eight other missions on display at the Stephen F. Udvar-Hazy Center of the Smithsonian Institution’s National Air and Space Museum in Chantilly, Virginia The Spacelab long module that flew on STS-9 and eight other missions on display at the Stephen F. Udvar-Hazy Center of the Smithsonian Institution’s National Air and Space Museum in Chantilly, Virginia The Spacelab long module that flew on STS-9 and eight other missions on display at the Stephen F. Udvar-Hazy Center of the Smithsonian Institution’s National Air and Space Museum in Chantilly, Virginia
The Spacelab long module that flew on STS-9 and eight other missions on display at the Stephen F. Udvar-Hazy Center of the Smithsonian Institution’s National Air and Space Museum in Chantilly, Virginia.

Enjoy the crew narrate a video about the STS-9 mission. Read Shaw’s, Garriott’s, and Parker’s recollections of the STS-9 mission in their oral histories with the JSC History Office.

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Webb Telescope: A prominent protostar in Perseus

Webb Telescope: A prominent protostar in Perseus

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Webb Telescope: A prominent protostar in Perseus

In the lower half of the image is a narrow, horizontal nebula that stretches from edge to edge. It is brightly coloured with more variety on its right side. In the upper half there is a glowing point with multi-coloured light radiating from it in all directions. A bright star with long diffraction spikes lies along the right edge, and a few smaller stars are spread around. The background is covered in a thin haze.

Webb Space Telescope reveals intricate details of the Herbig Haro object 797 (HH 797).

This new Picture of the Month from the NASA/ESA/CSA James Webb Space Telescope reveals intricate details of the Herbig Haro object 797 (HH 797). Herbig-Haro objects are luminous regions surrounding newborn stars (known as protostars), and are formed when stellar winds or jets of gas spewing from these newborn stars form shockwaves colliding with nearby gas and dust at high speeds. HH 797, which dominates the lower half of this image, is located close to the young open star cluster IC 348, which is located near the eastern edge of the Perseus dark cloud complex. The bright infrared objects in the upper portion of the image are thought to host two further protostars.

This image was captured with Webb’s Near-InfraRed Camera (NIRCam). Infrared imaging is powerful in studying newborn stars and their outflows, because the youngest stars are invariably still embedded within the gas and dust from which they are formed. The infrared emission of the star’s outflows penetrates the obscuring gas and dust, making Herbig-Haro objects ideal for observation with Webb’s sensitive infrared instruments. Molecules excited by the turbulent conditions, including molecular hydrogen and carbon monoxide, emit infrared light that Webb can collect to visualise the structure of the outflows. NIRCam is particularly good at observing the hot (thousands of degree Celsius) molecules that are excited as a result of shocks.

Image: Protostar in Perseus

In the lower half of the image is a narrow, horizontal nebula that stretches from edge to edge. It is brightly coloured with more variety on its right side. In the upper half there is a glowing point with multi-coloured light radiating from it in all directions. A bright star with long diffraction spikes lies along the right edge, and a few smaller stars are spread around. The background is covered in a thin haze.
The NASA/ESA/CSA James Webb Space Telescope reveals intricate details of the Herbig Haro object 797 (HH 797). Herbig-Haro objects are luminous regions surrounding newborn stars (known as protostars), and are formed when stellar winds or jets of gas spewing from these newborn stars form shockwaves colliding with nearby gas and dust at high speeds. HH 797, which dominates the lower half of this image, is located close to the young open star cluster IC 348, which is located near the eastern edge of the Perseus dark cloud complex. The bright infrared objects in the upper portion of the image are thought to host two further protostars. This image was captured with Webb’s Near-InfraRed Camera (NIRCam).
ESA/Webb, NASA & CSA, T. Ray (Dublin Institute for Advanced Studies)

Using ground-based observations, researchers have previously found that for cold molecular gas associated with HH 797, most of the red-shifted gas (moving away from us) is found to the south (bottom right), while the blue-shifted gas (moving towards us) is to the north (bottom left). A gradient was also found across the outflow, such that at a given distance from the young central star, the velocity of the gas near the eastern edge of the jet is more red-shifted than that of the gas on the western edge. Astronomers in the past thought this was due to the outflow’s rotation. In this higher resolution Webb image, however, we can see that what was thought to be one outflow is in fact made up of two almost parallel outflows with their own separate series of shocks (which explains the velocity asymmetries). The source, located in the small dark region (bottom right of center), and already known from previous observations, is therefore not a single but a double star. Each star is producing its own dramatic outflow. Other outflows are also seen in this image, including one from the protostar in the top right of center along with its illuminated cavity walls.

HH 797 resides directly north of HH 211 (separated by approximately 30 arcseconds), which was the feature of a Webb image release in September 2023.

Media Contacts

Laura Betzlaura.e.betz@nasa.gov, Rob Gutrorob.gutro@nasa.gov
NASA’s  Goddard Space Flight Center, Greenbelt, Md.

Bethany Downer –  Bethany.Downer@esawebb.org
ESA/Webb Chief Science Communications Officer

Downloads

Download full resolution images for this article from ESAWebb.org

Related Information

Star Formation

Piercing the Dark Birthplaces of Massive Stars with Webb

Webb Mission – https://science.nasa.gov/mission/webb/

Webb News – https://science.nasa.gov/mission/webb/latestnews/

Webb Images – https://science.nasa.gov/mission/webb/multimedia/images/

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NASA’s Fermi Mission Nets 300 Gamma-Ray Pulsars … and Counting

NASA’s Fermi Mission Nets 300 Gamma-Ray Pulsars … and Counting

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NASA’s Fermi Mission Nets 300 Gamma-Ray Pulsars … and Counting

A new catalog produced by a French-led international team of astronomers shows that NASA’s Fermi Gamma-ray Space Telescope has discovered 294 gamma-ray-emitting pulsars, while another 34 suspects await confirmation. This is 27 times the number known before the mission launched in 2008.

This visualization shows 294 gamma-ray pulsars, first plotted on an image of the entire starry sky as seen from Earth and then transitioning to a view from above our galaxy. The symbols show different types of pulsars. Young pulsars blink in real time except for the Crab, which pulses slower than in real time because its rate is only slightly lower than the video’s frame rate. Millisecond pulsars remain steady, pulsing too quickly to see. The Crab, Vela, and Geminga were among the 11 gamma-ray pulsars known before Fermi launched. Other notable objects are also highlighted. Distances are shown in light-years (abbreviated ly). Download high-resolution video and images from NASA’s Scientific Visualization Studio. Credit: NASA’s Goddard Space Flight Center

“Pulsars touch on a wide range of astrophysics research, from cosmic rays and stellar evolution to the search for gravitational waves and dark matter,” said study coordinator David Smith, research director at the Bordeaux Astrophysics Laboratory in Gironde, France, which is part of CNRS (the French National Center for Scientific Research). “This new catalog compiles full information on all known gamma-ray pulsars in an effort to promote new avenues of exploration.”

The catalog was published on Monday, Nov. 27, in The Astrophysical Journal Supplement.


Narrow beams of energy emerge from hot spots on the surface of a neutron star in this artist’s concept. When one of these beams sweeps past Earth, astronomers detect a pulse of light. Credit: NASA’s Goddard Space Flight Center Conceptual Image Lab

Pulsars are a type of neutron star, the city-sized leftover of a massive sun that has exploded as a supernova. Neutron stars, containing more mass than our Sun in a ball less than 17 miles wide, represent the densest matter astronomers can study directly. They possess strong magnetic fields, produce streams of energetic particles, and spin quickly – 716 times a second for the fastest known. Pulsars, in addition, emit narrow beams of energy that swing lighthouse-like through space as the objects rotate. When one of these beams sweeps past Earth, astronomers detect a pulse of emission.

The new catalog represents the work of 170 scientists across the globe. A dozen radio telescopes carry out regular monitoring of thousands of pulsars, and radio astronomers search for new pulsars within gamma-ray sources discovered by Fermi. Other researchers have teased out gamma-ray pulsars that have no radio counterparts through millions of hours of computer calculation, a process called a blind search.

More than 15 years after its launch, Fermi remains an incredible discovery machine, and pulsars and their neutron star kin are leading the way.

Elizabeth Hays

Elizabeth Hays

Fermi Project Scientist

Of the 3,400 pulsars known, most of them observed via radio waves and located within our Milky Way galaxy, only about 10% also pulse in gamma rays, the highest-energy form of light. Visible light has energies between 2 and 3 electron volts. Fermi’s Large Area Telescope can detect gamma rays with billions of times this energy, and other facilities have observed emission thousands of times greater still from the nearby Vela pulsar, the brightest persistent source in the sky for Fermi.


This movie shows the Vela pulsar in gamma rays detected by the Large Area Telescope aboard NASA’s Fermi observatory. A single pulsar cycle is repeated. Bluer colors indicate gamma rays with higher energies. Credit: NASA/DOE/Fermi LAT Collaboration

The Vela pulsar and its famous sibling in the Crab Nebula are young, solitary objects, formed about 11,000 and 970 years ago, respectively. Their emissions arise as their magnetic fields spin through space, but this also gradually slows their rotation. The younger Crab pulsar spins nearly 30 times a second, while Vela clocks in about a third as fast.

The Old and the Restless

Paradoxically, though, pulsars that are thousands of times older spin much faster. One example of these so-called millisecond pulsars (MSPs) is J1824-2452A. It whirls around 328 times a second and, with an age of about 30 million years, ranks among the youngest MSPs known.

Thanks to a great combination of gamma-ray brightness and smooth spin slowdown, the MSP J1231-1411 is an ideal “timer” for use in gravitational wave searches. By monitoring a collection of stable MSPs, astronomers hope to link timing changes to passing low-frequency gravitational waves – ripples in space-time – that cannot be detected by current gravitational observatories. It was discovered in one of the first radio searches targeting Fermi gamma-ray sources not associated with any known counterpart at other wavelengths, a technique that turned out to be exceptionally successful.

“Before Fermi, we didn’t know if MSPs would be visible at high energies, but it turns out they mostly radiate in gamma rays and now make up fully half of our catalog,” said co-author Lucas Guillemot, an associate astronomer at the Laboratory of Physics and Chemistry of the Environment and Space and the University of Orleans, France.

Along Come the Spiders

The presence of MSPs in binary systems offers a clue to understanding the age-spin paradox. Left to itself, a pulsar’s emissions slow it down, and with slower spin its emissions dim. But if closely paired with a normal star, the pulsar can pull a stream of matter from its companion that, over time, can spin up the pulsar.

“Spider” systems offer a glimpse of what happens next. They’re classified as redbacks or black widows – named for spiders known for consuming their mates. Black widows have light companions (less than about 5% of the Sun’s mass), while redbacks have heavier partners. As the pulsar spins up, its emissions and particle outflows become so invigorated that – through processes still poorly understood – it heats and slowly evaporates its companion. The most energetic spiders may fully evaporate their partners, leaving only an isolated MSP behind.

J1555-2908 is a black widow with a surprise – its gravitational web may have ensnared a passing planet. An analysis of 12 years of Fermi data reveals long-term spin variations much larger than those seen in other MSPs. “We think a model incorporating the planet as a third body in a wide orbit around the pulsar and its companion describes the changes a little better than other explanations, but we need a few more years of Fermi observations to confirm it,” said co-author Colin Clark, a research group leader at the Max Planck Institute for Gravitational Physics in Hannover, Germany.

Other curious binaries include the so-called transitional pulsars, such as J1023+0038, the first identified. An erratic stream of gas flowing from the companion to the neutron star may surge, suddenly forming a disk around the pulsar that can persist for years. The disk shines brightly in optical light, X-rays, and gamma rays, but pulses become undetectable. When the disk again vanishes, so does the high-energy light and the pulses return.


This artist’s concept illustrates a possible model for the transitional pulsar J1023. When astronomers can detect pulses in radio (green), the pulsar’s energetic outflow holds back its companion’s gas stream. Sometimes the stream surges, creating a bright disk around the pulsar that can persist for years. The disk shines brightly in X-rays, and gas reaching the neutron star produces jets that emit gamma rays (magenta), obscuring the pulses until the disk eventually dissipates. Credit: NASA’s Goddard Space Flight Center

Some pulsars don’t require a partner to switch things up. J2021+4026, a young, isolated pulsar located about 4,900 light-years away, underwent a puzzling “mode change” in 2011, dimming its gamma rays over about a week and then, years later, slowly returning to its original brightness. Similar behavior had been seen in some radio pulsars, but this was a first in gamma rays. Astronomers suspect the event may have been triggered by crustal cracks that temporarily changed the pulsar‘s magnetic field.

Farther afield, Fermi discovered the first gamma-ray pulsar in another galaxy, the neighboring Large Magellanic Cloud, in 2015. And in 2021, astronomers announced the discovery of a giant gamma-ray flare from a different type of neutron star (called a magnetar) located in the Sculptor galaxy, about 11.4 million light-years away.

“More than 15 years after its launch, Fermi remains an incredible discovery machine, and pulsars and their neutron star kin are leading the way,” said Elizabeth Hays, the mission’s project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

Explore the Fermi gamma-ray pulsar catalog on WorldWide Telescope

Max Planck Institute release

By Francis Reddy
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Media contact:
Claire Andreoli
claire.andreoli@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
(301) 286-1940

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Last Updated
Nov 28, 2023
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Francis Reddy
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Goddard Space Flight Center
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