Members Can Post Anonymously On This Site
6 min read
Hubble Celebrates 30th Anniversary of Servicing Mission 1
Astronaut F. Story Musgrave works in the space shuttle Endeavour’s cargo bay while the solar array panels on the Hubble Space Telescope are deployed during the final Servicing Mission 1 spacewalk. NASA In the pre-dawn hours on Dec. 2, 1993, the space shuttle Endeavour launched from Kennedy Space Center in Florida on a critical mission to repair NASA’s Hubble Space Telescope.
Hubble was designed to be serviced in space with components that astronauts can slide in and out of place. But prior to launch, no one expected the first servicing mission to be of such urgency.
For three years, Hubble had been the punchline of late-night comics and editorial cartoons: the telescope that couldn’t see straight. Since its deployment in 1990, the telescope had been beaming blurry images back to Earth, the result of a flaw in the shape of its primary mirror. Though the mirror was off by only one-fiftieth the width of a human hair, the error had devastating consequences: the light from the mirror didn’t focus quite right. While the images were still better than those taken from Earth and science was still possible, their quality was not what the world expected.
The sense that you got was everybody was looking at the servicing and repair of the Hubble Space Telescope as the mission that could prove NASA’s worth … There was this overarching focus and pressure on the success of this mission.
Servicing Mission 1 Astronaut
Servicing Mission 1 was the solution. Aboard the shuttle were the Wide Field and Planetary Camera 2 (WFPC2) and Corrective Optics Space Telescope Axial Replacement (COSTAR), along with other critical components to upgrade the telescope. WFPC2, responsible for the telescope’s visually impactful images, had built-in corrective optics to compensate for the mirror flaw and would replace the Wide Field/Planetary Camera that Hubble launched with. COSTAR was a refrigerator-sized component containing a constellation of mirrors, some only the size of a U.S. nickel, intended to correct and redirect light to the telescope’s other cameras and spectrographs.
Astronaut Kathryn C. Thornton grips a tool to perform servicing mission tasks on the Hubble Space Telescope during the fourth spacewalk of Servicing Mission 1. NASA The shuttle’s crew of seven astronauts was aware that not only Hubble’s fate was on their shoulders, but the public perception of NASA and its space program as well.
“If the Hubble repair is a failure, we can write off space science for the foreseeable future,” John Bahcall, the late astrophysicist who advocated for the telescope and a member of its science working group, told the New York Times in 1993.
Credit: NASA’s Goddard Space Flight Center; Lead Producer: Grace Weikert On Dec. 2, 2023, NASA commemorates the 30th anniversary of Servicing Mission 1 and its success in transforming Hubble into one of NASA’s greatest triumphs: a shining example of human ingenuity in the face of adversity.
During one of the most complex spacewalking missions ever attempted, astronauts conducted five extravehicular activities, totaling over 35 hours. They removed the High Speed Photometer instrument to add COSTAR and swapped out the original Wide Field/Planetary Camera for the Wide Field and Planetary Camera 2. They also installed other critical components to upgrade the telescope.
The crew of Servicing Mission 1 poses for a portrait on the space shuttle. In the front row from left to right are Swiss scientist Claude Nicollier, mission specialist; Kenneth D. Bowersox, pilot; and Richard O. Covey, mission commander. In the back row are the spacewalkers on this flight: F. Story Musgrave, payload commander; Jeffrey A. Hoffman, mission specialist; Kathryn D. Thornton, mission specialist; and Thomas D. Akers, mission specialist. NASA At 1 a.m. on December 18, 1993, about a week after the mission had ended, astronomers gathered around computers at the Space Telescope Science Institute in Baltimore to witness the first new image from the telescope: a star, shining clear and pristine in the image without the hazy effects of Hubble’s flawed mirror. The new images were so dramatically different that even though the telescope needed around 13 weeks for adjustment to reach its full capabilities, NASA released them early. “It’s fixed beyond our wildest expectations,” said Ed Weiler, Hubble chief scientist during SM1, at a January 1994 press conference.
The look on people’s faces as this picture came up – this was an old [cathode ray] tube-type TV. It took a while for it to build up, but it got clearer and clearer and clearer. Everybody starts shouting.
Hubble chief scientist during SM1
Images of spiral galaxy M100 show the improvement in Hubble’s vision between Wide Field/Planetary Camera and its replacement instrument, the Wide Field and Planetary Camera 2. NASA, STScI Senator Barbara Mikulski of Maryland, who had advocated diligently for Hubble, was the first to show off the new images to the public at the Jan. 13 press conference. “I’m happy to announce today that after its launch in 1990 and some of its earlier disappointments, the trouble with Hubble is over,” she said.
Sen. Barbara Mikulski displays a picture showing the difference between a star image taken before COSTAR’s installation and the same star after Servicing Mission 1 during the Jan. 13, 1993 press conference announcing the success of the mission. NASA Though Servicing Mission 1 is best remembered for its resolution of Hubble’s blurry vision, it accomplished a host of additional tasks that helped transform the telescope into the astronomical powerhouse it remains today.
By the time Servicing Mission 1 launched, the telescope’s gyroscopes – delicate pieces of equipment required to steer and point Hubble – were already breaking down. Three of the six gyroscopes, or gyros, aboard Hubble had failed. The other three – typically kept as backups – were in operation, the minimum number needed to keep Hubble collecting science data. Astronauts replaced four gyroscopes, a fix that would help keep the telescope running smoothly for several years.
Early in Hubble’s time in orbit, NASA discovered that the telescope’s solar arrays would expand and contract excessively in the alternating heat and cold of space as the telescope traveled in and out of sunlight, causing them to vibrate. This forced engineers to use Hubble’s computing capacity to compensate for the “jitter” and reduced observation time. Astronauts replaced Hubble’s solar arrays with new versions that brought the natural jitter down to acceptable levels.
Astronauts also performed an augmentation whose vital importance would become clear a year later: upgrading Hubble’s flight computer with a co-processor and associated memory. Just weeks before the disintegrating comet Shoemaker-Levy 9 collided with Jupiter in 1994, Hubble went into a protective “safe mode” due to a memory unit problem in the main computer. Engineers were able to use that co-processor’s memory to fix the problem, capturing stunning images of the gas giant being pummeled by comet fragments.
Hubble Memorable Moments: Comet Impact
Find out more about Servicing Mission 1 and its accomplishments
Servicing Mission 1’s impact echoed far beyond Hubble. The mission was a showcase for tasks that could be done in space, proving humanity’s ability to perform highly complex work in orbit. The lessons learned from training for Hubble and from the servicing work itself would be built upon for other astronaut missions, including the four subsequent servicing visits to Hubble between 1997-2009. These additional missions to Hubble would enable the installation of new, cutting-edge instruments, repair of existing science instruments, and the replacement of key hardware, keeping Hubble at the forefront of astrophysics exploration.
Further, the lessons learned from Servicing Mission 1 were a guiding force for work on the International Space Station, and for missions yet to occur. “A lot of the knowledge that was developed there transferred directly to construction of the International Space Station and it’ll transfer to the things we do with [the future orbiting lunar space station] Gateway someday,” said Kenneth Bowersox, associate administrator for NASA’s Space Operations Mission Directorate, who was also astronaut on Servicing Mission 1. “And it’ll apply to things we do on the Moon and in deep space, going to Mars and beyond. It all links.”
To celebrate Servicing Mission 1, NASA is releasing a series of videos over the next two weeks featuring key players – astronauts, scientists, engineers, and more – as they reflect on the struggles and triumphs of that time, as well as the emotional and personal impact that Hubble and SM1 had on their lives. Follow @NASAHubble on X, Instagram, and Facebook, or go to nasa.gov/hubble to watch as the series kicks off this weekend.
Last Updated Dec 01, 2023 Editor Andrea Gianopoulos Contact Location Goddard Space Flight Center Related Terms
Astrophysics Astrophysics Division Goddard Space Flight Center Hubble Space Telescope Missions Science & Research Science Mission Directorate Keep Exploring Discover More Topics From NASA
Hubble Space Telescope
Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.
James Webb Space Telescope
Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…
View the full article
Earlier this year, Congress passed something called the UAP Disclosure Act of 2023. The law requires to tell the public what it knows about the countless unidentified flying objects that have been spotted in the skies above Earth over the past 3,000 years.
It's designed to be, and it very well could be a transformative piece of legalization. And it comes at a time when we can say with confidence that the most unlikely sounding theories about UFOs are actually true.
Yes, these things are real. They're not all weather balloons. They're not experimental aircraft from this or any other country. Whatever they are, they are not of human origin. Nor do they behave according to the laws of known physics.
And yes, the US government currently has physical evidence that they exist. That means wreckage of the craft as well as the bodies of the beings that flew them.
Now, the Office of Global Access (OGA), a wing of the Central Intelligence Agency's Science and Technology Directorate, has played a central role since 2003 in orchestrating the collection of what could be alien spacecraft.
This CIA's secret office has conducted UFO retrieval missions on at least nine crash sites around the world, according to Dailymail.
The CIA has a 'system in place that can discern UFOs while they're still cloaked' and special military units are sent to salvage the wreckage and then often hands the wreckage or material over to private aerospace/defense contractors (who are working close with the US government) for analysis.
So the question is, now that the UAP Disclosure Act has passed, when can the rest of us see the information that we paid for and in fact, own? Well, not so fast, it turns out.
Just when it seemed the UAP Disclosure Act was finally going to lift the veil on decades of secrets, two Republican lawmakers voted against the legislation. The two members happen to be especially powerful this term. They are Congressman Mike Rogers of Alabama, who is the chairman of the House Armed Services Committee, and Congressman Mike Turner of Ohio, who is chairman of the House Intel Committee.
Why is this happening and what could be their potential motives?
Above image: Watch video from Chris Letho: UAP disclosure under threat - What is the roadblock - Follow the Money!
One of the great secrets of Washington know to everyone inside Washington is that many of the most powerful members of Congress do not work for their constituents, much less for the rest of us, for the country at large. They are instead puppets and they are controlled effectively by the permanent bureaucracy, including through bribery and blackmail.
Some people saying the UAP Disclosure Act was founded to pave the way for controlled UFO disclosure, now that is not going to happen as long as key politicians are controlled and instructed to violate in letter and in spirit federal law and to hide the truth about UFOs from the American public.
But why these key politicians may not want you to know the truth? Just connect the dots and follow the money trail leading to defense contractors! View the full article
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Last Updated Nov 28, 2023 Related Terms
NASA History Space Shuttle STS-9 Explore More
9 min read Spacelab 1: A Model for International Cooperation
Article 22 hours ago 10 min read Thanksgiving Celebrations in Space
Article 6 days ago 12 min read 55 Years Ago: Eight Months Before the Moon Landing
Article 2 weeks ago View the full article
7 min read
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.
supports HTML5 video
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.
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.
supports HTML5 video
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.
supports HTML5 video
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.
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Last Updated Nov 28, 2023 Editor Francis Reddy Location Goddard Space Flight Center Related Terms
Astrophysics Binary Stars Fermi Gamma-Ray Space Telescope Gamma Rays Goddard Space Flight Center Neutron Stars Pulsars Stars The Universe Keep Exploring Discover More Topics From NASA
Humans in Space
View the full article
5 min read
‘Digital Winglets’ for Real Time Flight Paths
Alaska Airlines Captain Bret Peyton looks at route options presented by Traffic Aware Strategic Aircrew Requests (TASAR) during a test of the software at Langley Research Center. The program connects to onboard systems and runs on a tablet called an Electronic Flight Bag.Credit: David Wing Before airplanes even reach the runway, pilots must file a plan to inform air traffic controllers where they’re going and the path they are going to take. When planes are in the air, however, that plan often changes. From turbulence causing passenger discomfort and additional fuel use to unexpected weather patterns blocking the original path, pilots have to think on the fly and inform air traffic controllers of any modifications to their routes.
In the past, these changes would have to happen suddenly and with little lead time. But as airplanes have become more digitally connected, the flying machines can take advantage of the additional data they receive, and a NASA-developed technology can help pilots find the best path every time.
NASA has explored methods to improve aircraft efficiency since its inception. Among the agency’s most famous contributions are winglets, upturned vertical flanges at the ends of airplane wings that eliminate turbulence at the wingtip and significantly save fuel. Fuel efficiency is critical to future aircraft development, as it not only improves performance and the weight it can carry but also reduces the amount of greenhouse gases released into the atmosphere.
David Wing, principal researcher of air traffic management at NASA’s Langley Research Center in Hampton, Virginia, develops advanced autonomy systems for aircraft, allowing operators to directly manage flight paths in crowded skies. He noticed some of the same technology used for safe routing could also optimize routes for flights already in the air. Allowing pilots to identify a better path as soon as it’s available could save time and money.
“Air traffic control is there to keep the aircraft safely separated from other aircraft,” said Wing. “So, the trick is, when you need to change your routing, what route do you ask for, and how much will it save you?”
In this screenshot of the APiJET Digital Winglets software based on NASA technology, a route is plotted along navigational waypoints, presenting three options that would save fuel and time based on real-time information. Credit: APiJET LLC Under Wing’s lead, NASA developed Traffic-Aware Strategic Aircrew Requests (TASAR), a piece of software pilots and ground operations teams can use to find better routes in transit. TASAR uses a genetic algorithm, a machine learning system that finds the optimal answer by pitting hundreds of route changes against each other and seeing which one comes out on top. TASAR takes a map of the area and draws hundreds of lines radiating from the airplane. These lines represent potential routes the plane could take. The software whittles down every route it generates, avoiding ones that stray into no-fly zones or dangerous weather systems or get too close to other aircraft until it’s found the most efficient route the airplane can take. Then, it’s up to the pilot to take the computer’s advice. Information is constantly updated using sensors on the airplane and connections to ground-based services, which TASAR takes into account.
“The algorithms had been tested and matured already for many years in our research, so they were in pretty good shape,” Wing said. “But we had to connect this system to a real aircraft, which meant that we needed to be able to access data from the onboard avionics.”
On NASA test flights, the software worked perfectly, but for TASAR to break into more flights, commercial planes needed to be able to access large amounts of data. As it turned out, a solution was close at hand.
The company iJET originally built components that could keep planes connected to the latest information available on the ground, which often wasn’t available in the sky. After developing better antennas, the company soon began working on a new integrated computer system for airplanes to collect data and stay connected to ground-based information sources. When looking for a “killer app” for the system, the company discovered TASAR.
“We saw that NASA was getting to the conclusion of this work, and we took a business decision to pick up the baton,” said Rob Green, CEO of the company.
After being acquired by another company called Aviation Partners, the Seattle-based company was renamed APiJET in 2018 and became the first company to license TASAR from NASA. APiJET proceeded to tie the software to the in-flight computer system. The company’s version of TASAR is called Digital Winglets, named after the NASA invention.
Frontier Airlines was among the first companies to test Digital Winglets for its fleet of aircraft. In testing, the commercial implementation of NASA’s TASAR technology provided fuel savings of 2%, which adds up at airline scale. Credit: Frontier Airlines The app runs on electronic flight bags, computer devices approved for use in flight operations by the Federal Aviation Administration, most commonly Apple iPads. Green said there are no plans to integrate it directly into a cockpit instrument panel because updating an app is easier. In testing with Alaska Airlines, Green said the program saved 2% on fuel, working out to approximately 28,000 pounds of fuel per hundred flights.
“Two percent may not sound like much, but little savings can really add up at airline scale,” Green said.
Several more airlines have tested the technology, and Frontier Airlines is currently field testing for a potential deployment of Digital Winglets across its fleet. APiJET still keeps in touch with the developers at NASA to further research TASAR’s benefits and build out its commercial capabilities.
“Everybody that worked on TASAR at NASA should be really proud of their direct impact on fuel savings and carbon reduction,” Green said. “It’s a lot to wrap your head around, but it works.”
NASA has a long history of transferring technology to the private sector. The agency’s Spinoff publication profiles NASA technologies that have transformed into commercial products and services, demonstrating the broader benefits of America’s investment in its space program. Spinoff is a publication of the Technology Transfer program in NASA’s Space Technology Mission Directorate (STMD).
For more information on how NASA brings space technology down to Earth, visit:
Last Updated Nov 22, 2023 Related Terms
Spinoffs Technology Transfer Technology Transfer & Spinoffs Explore More
5 min read NASA’s Webb Telescope Improves Simulation Software
Article 3 weeks ago 3 min read NASA Makes It Easier to Find Assistive Technologies for Licensing
Article 1 month ago 4 min read Goddard Physicist Inducted to NASA Inventors Hall of Fame
NASA physicist Edward J. Wollack is among those inducted into the NASA Inventors Hall of…
Article 2 months ago Keep Exploring Discover More Topics From NASA
Humans in Space
View the full article
Check out these Videos