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By Amazing Space
X-FLARE Update - Did You See This Giant Solar Flare Today? 13th May - AR4086 Flare and CME
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By Space Force
U.S. Space Force Chief of Space Operations Gen. Chance Saltzman emphasized the critical role of partnerships and the growing strategic importance of space during his remarks at the 2nd International AeroSpace Power Conference in Rome.
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By NASA
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
The blazar BL Lacertae, a supermassive black hole surrounded by a bright disk and jets oriented toward Earth, provided scientists with a unique opportunity to answer a longstanding question: How are X-rays generated in extreme environments like this?
NASA’s IXPE (Imaging X-ray Polarimetry Explorer) collaborated with radio and optical telescopes to find answers. The results (preprint available here), to be published in the journal Astrophysical Journal Letters, show that interactions between fast-moving electrons and particles of light, called photons, must lead to this X-ray emission.
This artist’s concept depicts the central region of the blazar BL Lacertae, a supermassive black hole surrounded by a bright disk and a jet oriented toward Earth. The galaxy’s central black hole is surrounded by swirls of orange in various shades representing the accretion disk of material falling toward the black hole. While black holes are known for pulling in material, this accretion process can result in the ejection of jets of electrons at nearly the speed of light. The jet of matter is represented by the cone of light that starts at the center of the black hole and widens out as it reaches the bottom of the image. It is streaked with lines of white, pink and purple which represent helix-shaped magnetic fields. We can observe these jets in many wavelengths of light including radio, optical, and X-ray. NASA’s Imaging X-ray Polarimetry Explorer (IXPE) recently collaborated with radio and optical telescopes to observe this jet and determine how the X-rays are generated in these types of celestial environments.NASA/Pablo Garcia Scientists had two competing possible explanations for the X-rays, one involving protons and one involving electrons. Each of these mechanisms would have a different signature in the polarization of X-ray light. Polarization is a property of light that describes the average direction of the electromagnetic waves that make up light.
If the X-rays in a black hole’s jets are highly polarized, that would mean that the X-rays are produced by protons gyrating in the magnetic field of the jet or protons interacting with jet’s photons. If the X-rays have a lower polarization degree, it would suggest that electron-photons interactions lead to X-ray production.
IXPE, which launched Dec. 9, 2021, is the only satellite flying today that can make such a polarization measurement.
“This was one of the biggest mysteries about supermassive black hole jets” said Iván Agudo, lead author of the study and astronomer at the Instituto de Astrofísica de Andalucía – CSIC in Spain. “And IXPE, with the help of a number of supporting ground-based telescopes, finally provided us with the tools to solve it.”
Astronomers found that electrons must be the culprits through a process called Compton Scattering. Compton scattering (or the Compton effect) happens when a photon loses or gains energy after interacting with a charged particle, usually an electron. Within jets from supermassive black holes, electrons move near the speed of light. IXPE helped scientists learn that, in the case of a blazar jet, the electrons have enough energy to scatter photons of infrared light up to X-ray wavelengths.
BL Lacertae (BL Lac for short) is one of the first blazars ever discovered, originally thought to be a variable star in the Lacerta constellation. IXPE observed BL Lac at the end of November 2023 for seven days along with several ground-based telescopes measuring optical and radio polarization at the same time. While IXPE observed BL Lac in the past, this observation was special. Coincidentally, during the X-ray polarization observations, the optical polarization of BL Lac reached a high number: 47.5%.
“This was not only the most polarized BL Lac has been in the past 30 years, this is the most polarized any blazar has ever been observed!” said Ioannis Liodakis, one of the primary authors of the study and astrophysicist at the Institute of Astrophysics – FORTH in Greece.
IXPE found the X-rays were far less polarized than the optical light. The team was not able to measure a strong polarization signal and determined that the X-rays cannot be more polarized than 7.6%. This proved that electrons interacting with photons, via the Compton effect, must explain the X-rays.
The fact that optical polarization was so much higher than in the X-rays can only be explained by Compton scattering.
Steven Ehlert
Project Scientist for IXPE at Marshall Space Flight Center
“The fact that optical polarization was so much higher than in the X-rays can only be explained by Compton scattering”, said Steven Ehlert, project scientist for IXPE and astronomer at the Marshall Space Flight Center.
“IXPE has managed to solve another black hole mystery” said Enrico Costa, astrophysicist in Rome at the Istituto di Astrofísica e Planetologia Spaziali of the Istituto Nazionale di Astrofísica. Costa is one of the scientists who conceived this experiment and proposed it to NASA 10 years ago, under the leadership of Martin Weisskopf, IXPE’s first principal investigator. “IXPE’s polarized X-ray vision has solved several long lasting mysteries, and this is one of the most important. In some other cases, IXPE results have challenged consolidated opinions and opened new enigmas, but this is how science works and, for sure, IXPE is doing very good science.”
What’s next for the blazar research?
“One thing we’ll want to do is try to find as many of these as possible,” Ehlert said. “Blazars change quite a bit with time and are full of surprises.”
More about IXPE
IXPE, which continues to provide unprecedented data enabling groundbreaking discoveries about celestial objects across the universe, is a joint NASA and Italian Space Agency mission with partners and science collaborators in 12 countries. IXPE is led by NASA’s Marshall Space Flight Center in Huntsville, Alabama. BAE Systems, Inc., headquartered in Falls Church, Virginia, manages spacecraft operations together with the University of Colorado’s Laboratory for Atmospheric and Space Physics in Boulder. Learn more about IXPE’s ongoing mission here:
https://www.nasa.gov/ixpe
Elizabeth Landau
NASA Headquarters
elizabeth.r.landau@nasa.gov
202-358-0845
Lane Figueroa
Marshall Space Flight Center, Huntsville, Ala.
lane.e.figueroa@nasa.gov
256.544.0034
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Last Updated May 06, 2025 EditorBeth RidgewayContactElizabeth R. Landauelizabeth.r.landau@nasa.govLocationMarshall Space Flight Center Related Terms
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Black Holes
Black Holes Black holes are among the most mysterious cosmic objects, much studied but not fully understood. These objects aren’t…
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By NASA
3 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
From left, Ramon Pedoto, Nathan Walkenhorst, and Tyrell Jemison review information at NASA’s Marshall Space Flight Center in Huntsville, Alabama. The three team members developed new automation tools at Marshall for flight controllers working with the International Space Station (Credit: NASA/Tyrell Jemison Two new automation tools developed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, are geared toward improving operations for flight controllers working with the International Space Station from the Huntsville Operations Support Center.
The tools, called AutoDump and Permanently Missing Intervals Checker, will free the flight control team to focus on situational awareness, anomaly response, and real-time coordination.
The space station experiences routine loss-of-signal periods based on communication coverage as the space station orbits the Earth. When signal is lost, an onboard buffer records data that could not be downlinked during that period. Following acquisition of signal, flight controllers previously had to send a command to downlink, or “dump,” the stored data.
The AutoDump tool streamlines a repetitive data downlinking command from flight controllers by detecting a routine loss-of-signal, and then autonomously sending the command to downlink data stored in the onboard buffer when the signal is acquired again. Once the data has been downlinked, the tool will automatically make an entry in the console log to confirm the downlink took place.
“Reliably and quickly sending these dump commands is important to ensure that space station payload developers can operate from the most current data,” said Michael Zekoff, manager of Space Systems Operations at Marshall.
As a direct result of this tool, we have eliminated the need to manually perform routine data dump commands by as much as 40% for normal operations.
Michael Zekoff
Space Systems Operations Manager
AutoDump was successfully deployed on Feb. 4 in support of the orbiting laboratory.
The other tool, known as the Permanently Missing Intervals Checker, is another automated process coming online that will improve team efficiency.
Permanently missing intervals are gaps in the data stream where data can be lost due to a variety of reasons, including network fluctuations. The missing intervals are generally short but are documented so the scientific community and other users have confirmation that the missing data is unable to be recovered.
“The process of checking for and documenting permanently missing intervals is challenging and incredibly time-consuming to make sure we capture all the payload impacts,” said Nathan Walkenhorst, a NASA contractor with Bailey Collaborative Solutions who serves as a flight controller specialist.
The checker will allow NASA to quickly gather and assess payload impacts, reduce disruptions to operations, and allow researchers to get better returns on their science investigations. It is expected to be deployed later this year.
In addition to Walkenhorst, Zekoff also credited Ramon Pedoto, a software architect, and Tyrell Jemison, a NASA contractor and data management coordinator with Teledyne Brown Engineering Inc, for their work in developing the automation tools. The development of the tools also requires coordination between flight control and software teams at Marshall, followed by extensive testing in both simulated and flight environments, including spacecraft operations, communications coverage, onboard anomalies, and other unexpected conditions.
“The team solicited broad review to ensure that the tool would integrate correctly with other station systems,” Zekoff said. “Automated tools are evaluated carefully to prevent unintended commanding or other consequences. Analysis of the tools included thorough characterization of the impacts, risk mitigation strategies, and approval by stakeholders across the International Space Station program.”
The Huntsville Operations Support Center provides payload, engineering, and mission operations support to the space station, the Commercial Crew Program, and Artemis missions, as well as science and technology demonstration missions. The Payload Operations Integration Center within the Huntsville Operations Support Center operates, plans, and coordinates the science experiments onboard the space station 365 days a year, 24 hours a day.
For more information on the International Space Station, visit:
www.nasa.gov/international-space-station/
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Last Updated Apr 11, 2025 EditorBeth RidgewayLocationMarshall Space Flight Center Related Terms
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NASA’s Juno Back to Normal Operations After Entering Safe Mode
NASA’s Juno flies above Jupiter’s Great Red Spot in this artist’s concept. NASA/JPL-Caltech The spacecraft was making its 71st close approach to Jupiter when it unexpectedly entered into a precautionary status.
Data received from NASA’s Juno mission indicates the solar-powered spacecraft went into safe mode twice on April 4 while the spacecraft was flying by Jupiter. Safe mode is a precautionary status that a spacecraft enters when it detects an anomaly. Nonessential functions are suspended, and the spacecraft focuses on essential tasks like communication and power management. Upon entering safe mode, Juno’s science instruments were powered down, as designed, for the remainder of the flyby.
The mission operations team has reestablished high-rate data transmission with Juno, and the spacecraft is currently conducting flight software diagnostics.The team will work in the ensuing days to transmit the engineering and science data collected before and after the safe-mode events to Earth.
Juno first entered safe mode at 5:17 a.m. EDT, about an hour before its 71st close passage of Jupiter — called perijove. It went into safe mode again 45 minutes after perijove. During both safe-mode events, the spacecraft performed exactly as designed, rebooting its computer, turning off nonessential functions, and pointing its antenna toward Earth for communication.
Of all the planets in our solar system, Jupiter is home to the most hostile environment, with the radiation belts closest to the planet being the most intense. Early indications suggest the two Perijove 71 safe-mode events occurred as the spacecraft flew through these belts. To block high-energy particles from impacting sensitive electronics and mitigate the harmful effects of the radiation, Juno features a titanium radiation vault.
Including the Perijove 71 events, Juno has unexpectedly entered spacecraft-induced safe mode four times since arriving at Jupiter in July 2016: first, in 2016 during its second orbit, then in 2022 during its 39th orbit. In all four cases, the spacecraft performed as expected and recovered full capability.
Juno’s next perijove will occur on May 7 and include a flyby of the Jovian moon Io at a distance of about 55,300 miles (89,000 kilometers).
More About Juno
NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA’s New Frontiers Program, which is managed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington. The Italian Space Agency (ASI) funded the Jovian InfraRed Auroral Mapper. Lockheed Martin Space in Denver built and operates the spacecraft. Various other institutions around the U.S. provided several of the other scientific instruments on Juno.
More information about Juno is available at:
https://www.nasa.gov/juno
News Media Contacts
DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.gov
Karen Fox / Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov
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Southwest Research Institute, San Antonio
210-522-2254
dschmid@swri.org
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Last Updated Apr 09, 2025 Related Terms
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