SPACE/COSMOS
AFP
TOKYO: A company aiming to become Japan’s first private firm to put a satellite into orbit postponed its rocket launch on Saturday, after its first try ended in a mid-air explosion.
Tokyo-based Space One’s Kairos rocket was to make its second blast-off from the company’s launch pad in the rural western region of Wakayama at 11am, but called it off in a move announced about 20 minutes before the scheduled launch.
“During the final decision-making process for the launch, we analysed the weather conditions and determined that the wind speeds above an altitude of 10 kilometres (6.2 miles) were so strong that it was not suitable for launch,” Space One executive Kozo Abe told reporters.
Abe said the company plans to make another attempt today on Sunday at 11am. “We will do our utmost to prepare for tomorrow’s launch,” he said.
Private firms are offering cheaper and more frequent space exploration opportunities than governments, and Space One hopes to emulate Elon Musk’s SpaceX, which has contracts with NASA and the Pentagon. But first, it needs to get off the ground.
The solid-fuel Kairos, carrying a small government test satellite, lifted off for the first time in March from the Space One launch pad, dubbed Spaceport Kii.
Published in Dawn, December 15th, 2024
M87's powerful jet unleashes rare gamma-ray outburst
Nagoya City University
image:
Light curve of the gamma-ray flare (bottom) and collection of quasi-simulated images of the M87 jet (top) at various scales obtained in radio and X-ray during the 2018 campaign. The instrument, the wavelength observation range and scale are shown at the top left of each image.
view moreCredit: EHT Collaboration, Fermi-LAT Collaboration, H.E.S.S. Collaboration, MAGIC Collaboration, VERITAS Collaboration, EAVN Collaboration
Also known as Virgo A or NGC 4486, M87 is the brightest object in the Virgo cluster of galaxies, the largest gravitationally bound type of structure in the universe. It came to fame in April 2019 after scientists from EHT released the first image of a black hole in its center. Led by the EHT multi wavelength working group, a study published in Astronomy and Astrophysics Journal presents the data from the second EHT observational campaign conducted in April 2018, involving over 25 terrestrial and orbital telescopes. The authors report the first observation of a high-energy gamma-ray flare in over a decade from the supermassive black hole M87, based on nearly simultaneous spectra of the galaxy spanning the broadest wavelength range ever collected.
"We were lucky to detect a gamma-ray flare from M87 during this Event Horizon Telescope's multi-wavelength campaign. This marks the first gamma-ray flaring event observed in this source in over a decade, allowing us to precisely constrain the size of the region responsible for the observed gamma-ray emission. Observations—both recent ones with a more sensitive EHT array and those planned for the coming years—will provide invaluable insights and an extraordinary opportunity to study the physics surrounding M87’s supermassive black hole. These efforts promise to shed light on the disk-jet connection and uncover the origins and mechanisms behind the gamma-ray photon emission." says Giacomo Principe, one of the paper coordinators, a researcher at the University of Trieste associated with INAF and INFN. The article has been accepted for publication in Astronomy & Astrophysics.
The relativistic jet examined by the researchers is surprising in its extent, reaching sizes that exceed the black hole’s event horizon by tens of millions of times (7 orders of magnitude) - akin to the difference between the size of a bacterium and the largest known blue whale.
The energetic flare, which lasted approximately three days and suggests an emission region of less than three light-days in size (~170 AU, where 1 Astronomical Unit is the distance from the Sun to Earth), revealed a bright burst of high-energy emission—well above the energies typically detected by radio telescopes from the black hole region.
"The activity of this supermassive black hole is highly unpredictable – It is hard to forecast when a flare will occur. The contrasting data obtained in 2017 and 2018, representing its quiescent and active phases respectively, provide crucial insights into unraveling the activity cycle of this enigmatic black hole." says Kazuhiro Hada at Nagoya City University, who led radio observations and analysis of the multi-wavelength campaign.
"The duration of a flare roughly corresponds to the size of the emission region. The rapid variability in gamma rays indicates that the flare region is extremely small, only approximately ten times the size of the central black hole. Interestingly, the sharp variability observed in gamma rays was not detected in other wavelengths. This suggests that the flare region has a complex structure and exhibits different characteristics depending on the wavelength." explains Daniel Mazin at the Institute for Cosmic Ray Research, The University of Tokyo, a member of the MAGIC telescope team that detected the gamma ray flare.
The second EHT and multi-wavelength campaign in 2018 leveraged more than two dozen high-profile observational facilities, including NASA’s Fermi-LAT, HST, NuSTAR, Chandra, and Swift telescopes, together with the world’s three largest Imaging Atmospheric Cherenkov Telescope arrays (H.E.S.S., MAGIC and VERITAS). These observatories are sensitive to X-ray photons as well as high-energy very-high-energy (VHE) gamma-rays, respectively. During the campaign, the LAT instrument aboard the Fermi space observatory detected an increase in high-energy gamma-ray flux with energies up to billions of times greater than visible light. Chandra and NuSTAR then collected high-quality data in the X-ray band. The East Asian VLBI Network (EAVN) radio observations show an apparent annual change in the jet's position angle within a few microseconds of arc from the galaxy's core.
"By combining the information about the change in the jet direction, the brightness distribution of the ring observed by the EHT and the gamma-ray activity, we can better understand the mechanisms behind the production of the very-high-energy radiation." says Motoki Kino at Kogakuin University, a coordinator of the EAVN observations during the campaign.
Data also show a significant variation in the position angle of the asymmetry of the ring (the so-called event horizon of the black hole) and the jet’s position, suggesting a physical relation between these structures on very different scales. The researcher explains: “In the first image obtained during the 2018 observational campaign, it was seen that the emission along the ring was not homogeneous, thus presenting asymmetries (i.e., brighter areas). Subsequent observations conducted in 2018 and related to this paper confirmed the data, highlighting that the asymmetry's position angle had changed.”
The team also compared the observed broadband multi-wavelength spectra with theoretical emission models. "The flare in 2018 exhibited particularly strong brightening in gamma rays. It is possible that ultra-high-energy particles underwent additional acceleration within the same emission region observed in quiet states, or that new acceleration occurred in a different emission region." says Tomohisa Kawashima at the Institute for Cosmic Ray Research, who performed a simulation using a supercomputer installed at the National Astronomical Observatory of Japan.
“How and where particles are accelerated in supermassive black hole jets is a longstanding mystery. For the first time, we can combine direct imaging of the near event horizon regions during gamma-ray flares from particle acceleration events and test theories about the flare origins,” says Sera Markoff, a professor at the University of Amsterdam and co-author of the study.
This discovery paves the way for stimulating future research and potential breakthroughs in understanding the universe.
All the involved multi-wavelength facilities (IMAGE)
The observatories and telescopes that participated in the 2018 multiband campaign to detect the high-energy gamma-ray flare from the M87* black hole.
Credit
EHT Collaboration, Fermi-LAT Collaboration, H.E.S.S. Collaboration, MAGIC Collaboration, VERITAS Collaboration, EAVN Collaboration
Journal
Astronomy and Astrophysics
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Broadband Multi-wavelength Properties of M87 During the 2018 Event Horizon Telescope Campaign including a Very-High-Energy Gamma-ray Episode
Article Publication Date
13-Dec-2024
Astrophysicists capture astonishing images of gamma-ray flare from supermassive black hole M87
The jet is tens of millions of times larger than the black hole’s event horizon
Key takeaways
- The galaxy M87, located in the Virgo constellation, provided the first-ever photo of a black hole in 2019, when the Event Horizon Telescope captured an image of the supermassive black hole at the galaxy’s center.
- An international research team including UCLA has observed a teraelectronvolt gamma-ray flare seven orders of magnitude — tens of millions of times — larger than the event horizon, or surface of the black hole itself.
- A flare of this intensity — which has not been observed in over a decade — can offer crucial insights into how particles, such as electrons and positrons, are accelerated in the extreme environments near black holes.
The first-ever photo of a black hole rocked the world in 2019, when the Event Horizon Telescope, or EHT, published an image of the supermassive black hole at the center of the galaxy M87, also known as Virgo A or NGC 4486, located in the constellation of Virgo. This black hole is surprising scientists again with a teraelectronvolt gamma-ray flare — emitting photons billions of times more energetic than visible light. Such an intense flare has not been observed in over a decade, offering crucial insights into how particles, such as electrons and positrons, are accelerated in the extreme environments near black holes.
The jet coming out of the center of M87 is seven orders of magnitude — tens of millions of times — larger than the event horizon, or surface of the black hole itself. The bright burst of high-energy emission was well above the energies typically detected by radio telescopes from the black hole region. The flare lasted about three days and probably emerged from a region less than three light-days in size, or a little under 15 billion miles.
A gamma ray is a packet of electromagnetic energy, also known as a photon. Gamma rays have the most energy of any wavelength in the electromagnetic spectrum and are produced by the hottest and most energetic environments in the universe, such as regions around black holes. The photons in M87’s gamma ray flare have energy levels up to a few teraelectronvolts. Teraelectronvolts are used to measure the energy in subatomic particles and are equivalent to the energy of a mosquito in motion. This is a huge amount of energy for particles that are many trillion times smaller than a mosquito. Photons with several teraelectronvolts of energy are vastly more energetic than the photons that make up visible light.
As matter falls toward a black hole, it forms an accretion disk where particles are accelerated due to the loss of gravitational potential energy. Some are even redirected away from the black hole’s poles as a powerful outflow, called “jets,” driven by intense magnetic fields. This process is irregular, which often causes a rapid energy outburst called a “flare.” However, gamma rays cannot penetrate Earth’s atmosphere. Nearly 70 years ago, physicists discovered that gamma rays can be detected from the ground by observing the secondary radiation generated when they strike the atmosphere.
“We still don’t fully understand how particles are accelerated near the black hole or within the jet,” said Weidong Jin, a postdoctoral researcher at UCLA and a corresponding author of a paper describing the findings published by an international team of authors in Astronomy & Astrophysics. “These particles are so energetic, they’re traveling near the speed of light, and we want to understand where and how they gain such energy. Our study presents the most comprehensive spectral data ever collected for this galaxy, along with modeling to shed light on these processes.”
Jin contributed to analysis of the highest energy part of the dataset, called the very-high-energy gamma rays, which was collected by VERITAS — a ground-based gamma-ray instrument operating at the Fred Lawrence Whipple Observatory in southern Arizona. UCLA played a major role in the construction of VERITAS — short for Very Energetic Radiation Imaging Telescope Array System — participating in the development of the electronics to read out the telescope sensors and in the development of computer software to analyze the telescope data and to simulate the telescope performance. This analysis helped detect the flare, as indicated by large luminosity changes that are a significant departure from the baseline variability.
More than two dozen high-profile ground- and space-based observational facilities, including NASA’s Fermi-LAT, Hubble Space Telescope, NuSTAR, Chandra and Swift telescopes, together with the world’s three largest imaging atmospheric Cherenkov telescope arrays (VERITAS, H.E.S.S. and MAGIC) joined this second EHT and multi-wavelength campaign in 2018. These observatories are sensitive to X-ray photons as well as high-energy and very-high-energy gamma-rays, respectively.
One of the key datasets used in this study is called spectral energy distribution.
“The spectrum describes how energy from astronomical sources, like M87, is distributed across different wavelengths of light,” Jin said. “It’s like breaking the light into a rainbow and measuring how much energy is present in each color. This analysis helps us uncover the different processes that drive the acceleration of high-energy particles in the jet of the supermassive black hole.”
Further analysis by the paper’s authors found a significant variation in the position and angle of the ring, also called the event horizon, and the jet position. This suggests a physical relationship between the particles and the event horizon, at different size scales, influences the jet’s position.
“One of the most striking features of M87’s black hole is a bipolar jet extending thousands of light years from the core,” Jin said. “This study provided a unique opportunity to investigate the origin of the very-high-energy gamma-ray emission during the flare, and to identify the location where the particles causing the flare are being accelerated. Our findings could help resolve a long-standing debate about the origins of cosmic rays detected on Earth.”
Journal
Astronomy and Astrophysics
Northwestern University joins Giant Magellan Telescope International Consortium
Northwestern’s investment expands the Giant Magellan Telescope international consortium to 15 research institutions from the United States, Australia, Brazil, Chile, Israel, South Korea, and Taiwan
image:
As the 9th American institution to invest, Northwestern University expands the Giant Magellan Telescope international consortium to 15 members from the United States, Australia, Brazil, Chile, Israel, South Korea, and Taiwan.
view moreCredit: Damien Jemison, Giant Magellan Telescope – GMTO Corporation
PASADENA, CA – December 13, 2024 – The Giant Magellan Telescope announced today that Northwestern University has joined its international consortium to construct the $2.54 billion observatory.
Home to the world-renowned Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and the newly founded NSF-Simons AI Institute for the Sky (SkAI), Northwestern is at the forefront of advancing astrophysical research. Northwestern researchers will develop and apply cutting-edge artificial intelligence (AI) tools to enhance the Giant Magellan Telescope’s capabilities, enabling it to search for Earth-like planets across the Milky Way, investigate the Universe’s most energetic explosions, and explore the intricate relationship between galaxies and black holes.
“Northwestern University’s strength in AI, astrophysics, and engineering innovation makes them an important addition to our consortium,” said Dr. Walter Massey, Board Chair of the Giant Magellan Telescope and former Director of the National Science Foundation. “Their involvement further establishes the Giant Magellan Telescope as the telescope of choice for America’s top universities, now spanning institutions across Arizona, Texas, Illinois, Massachusetts, and Washington, D.C. This collaboration reflects a nationwide commitment to advancing astronomy and cementing U.S. leadership in manufacturing and scientific discovery.”
As a new partner, Northwestern joins a distinguished group of American institutions driving one of the largest public-private partnerships in science, which includes the University of Arizona, Carnegie Science, The University of Texas at Austin, the University of Chicago, Texas A&M University, Harvard University, the Smithsonian Institution, and Arizona State University. Together, these institutions award more than 30% of the nation’s Ph.D. degrees and invest more than $250 million annually in research and instrumentation for astronomy in the U.S. — fueling technology innovations and strengthening America’s manufacturing economy. Northwestern’s investment builds the consortium’s momentum as it awaits the National Science Foundation’s (NSF) decision regarding federal participation in the partnership, which would expand access in the Giant Magellan Telescope to include all U.S. scientists.
Recognized as a leader in cross-disciplinary collaborations, Northwestern is ranked #6 in U.S. News & World Report’s National Universities rankings and #11 in the Times Higher Education Interdisciplinary Science Rankings, which recognizes, incentivizes and celebrates interdisciplinary science in higher education around the globe. CIERA and Northwestern Astronomy also rank in the top 10 nationally for research impact and national awards for faculty. CIERA’s interdisciplinary approach connects astronomy research and education to computer science, engineering, high-performance computing, and beyond. Just this year, the NSF and Simons Foundation awarded Northwestern with a highly competitive grant to establish the SkAI Institute. The Institute, which unites researchers across disciplines to develop innovative, trustworthy AI tools for survey astronomy, especially motivated by the Vera C. Rubin Observatory, solidifies Northwestern as a leader at the forefront of AI and astrophysics.
With these strengths, Northwestern researchers will contribute essential expertise to the complex datasets generated by the Giant Magellan Telescope and will play a crucial role in ensuring the observatory achieves its full potential as a tool for humanity’s continuing exploration of the Universe when it is commissioned in the early 2030s.
"Northwestern's commitment to interdisciplinary research — particularly in astrophysics, AI, data science and engineering — positions us to lead the next wave of astronomical research,” Northwestern President Michael H. Schill said. “Our full partnership with the Giant Magellan Telescope Consortium is a testament to this vision. I am especially grateful for Vicky Kalogera's leadership and efforts to secure this partnership. This collaboration will provide unparalleled opportunities for our students and faculty to push the boundaries of research and innovation as we seek to understand the Universe.”
The Giant Magellan Telescope will deliver up to 200 times the resolution and sensitivity of today’s leading telescopes, offering unprecedented power for astronomical discovery. Unique among the new class of “extremely large telescopes,” it features the widest field of view and the only science instruments capable of detecting and analyzing Earth-like planets in the reflected light of their host stars. It will be the first ground- or space-based telescope, operating now or in the future, capable of such unprecedented detections. This revolutionary capability moves the field beyond traditional transit detection methods for the first time.
The Giant Magellan Telescope is now 40% under construction across 36 states and on track to be operational in Chile by the early 2030s.
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