SPACE/ COSMOS
Supermassive black holes halt rapid construction in an ancient celestial city
The James Webb Space Telescope has captured a group of massive galaxies ending their growth due to supermassive black holes about 11 billion light years away
Waseda University
image:
Results from the James Webb Telescope near-infrared camera clearly show that massive galaxies with active galactic nucleus feedback from supermassive black holes have lower star formation.
view moreCredit: Rhythm Shimakawa from Waseda University
Understanding how galaxies form and complete their growth is an area of fundamental focus in astrophysics. The dense regions of the universe, like galaxy clusters, are dominated by giant elliptical galaxies—massive, ancient galaxies that consist of old stars. Although the mechanism by which these giant elliptical galaxies halt star formation remains debated, one theory predicts that supermassive black holes (SMBHs) could play a key role. Their intense energy can suppress the gas supply to galaxies, which may lead to the formation of the giant elliptical galaxies seen today.
Against this backdrop, an international team of researchers investigated massive galaxies in an ancient galaxy cluster known as the Spiderweb protocluster, located 11 billion light years away (Fig. 1), using data from the James Webb Space Telescope (JWST). The research was led by Associate Professor Rhythm Shimakawa from Waseda University, Japan; Dr. Yusei Koyama from the National Astronomical Observatory of Japan; Prof. Tadayuki Kodama from Tohoku University, Japan; Dr. Helmut Dannerbauer and Dr. J. M. Perez-Martinez from the Instituto de Astrofísica de Canarias and Universidad de La Laguna, Spain; along with others who were a part of the team. Their findings were published in the Monthly Notices of the Royal Astronomical Society: Letters on December 18, 2024.
The team succeeded in obtaining high-resolution maps of the recombination lines of hydrogen, which indicate the activity of star formation and SMBHs, through the Near-Infrared Camera mounted on JWST. Detailed analysis showed that massive galaxies with active SMBHs exhibit no sign of star formation, meaning that their growth is severely hampered by SMBHs (Fig. 2). The results support the theoretical prediction that the formation of giant elliptical galaxies is linked with SMBH activity in the past.
“The Spiderweb protocluster has been studied by our team for more than 10 years using the Subaru Telescope and other facilities. With the new JWST data, we are now able to ‘answer the questions’ of understanding and predicting galaxy formation that we have accumulated,” remarks Dr. Shimakawa. He adds further, “This study marks a significant step forward in expanding our understanding of the co-evolution of SMBHs and galaxies in celestial cities.”
The Spiderweb protocluster, an ancient galaxy cluster 11 billion light years away
The team observed a galaxy cluster about 11 billion light years ago, which is one of the ancestors of galaxy clusters we see today. JWST Near-Infrared Camera has a spatial resolution ten times better than previous telescopes in the near-infrared wavelength around 4 microns, helping researchers achieve this feat.
Researchers break down the activities of star formation and SMBH occurring in galaxies
The team investigated the formation sites of giant elliptical galaxies. As a result, they find that star formation is suppressed along with the SMBH activity in about half of approximately 20 massive galaxies.
Credit
Rhythm Shimakawa from Waseda University
***
Reference
DOI: https://doi.org/10.1093/mnrasl/slae098
Authors: Rhythm Shimakawa1,2, Yusei Koyama3,4,5, Tadayuki Kodama6, Helmut Dannerbauer7,8, J. M. Pérez-Martínez7,8, Huub J. A. Röttgering9, Ichi Tanaka4, Chiara D’Eugenio7,8, Abdurrahman Naufal5, Kazuki Daikuhara6, and Yuheng Zhang7,8,10,11
Affiliations:
1Waseda Institute for Advanced Study (WIAS), Waseda University, Japan
2Center for Data Science, Waseda University, Japan
3National Astronomical Observatory of Japan (NAOJ), National Institutes of Natural Sciences, Japan
4Subaru Telescope, National Astronomical Observatory of Japan, National Institutes of Natural Sciences, Japan
5Department of Astronomical Science, The Graduate University for Advanced Studies, Japan
6Astronomical Institute, Tohoku University, Japan
7Instituto de Astrofísica de Canarias, Spain
8Universidad de La Laguna, Dpto. Astrofísica, Spain
9Leiden Observatory, Leiden University, the Netherlands
10Purple Mountain Observatory, Chinese Academy of Sciences, China
11School of Astronomy and Space Science, University of Science and Technology of China, China
About Waseda University
Located in the heart of Tokyo, Waseda University is a leading private research university that has long been dedicated to academic excellence, innovative research, and civic engagement at both the local and global levels since 1882. The University has produced many changemakers in its history, including nine prime ministers and many leaders in business, science and technology, literature, sports, and film. Waseda has strong collaborations with overseas research institutions and is committed to advancing cutting-edge research and developing leaders who can contribute to the resolution of complex, global social issues. The University has set a target of achieving a zero-carbon campus by 2032, in line with the Sustainable Development Goals (SDGs) adopted by the United Nations in 2015.
To learn more about Waseda University, visit https://www.waseda.jp/top/en
About Associate Professor Rhythm Shimakawa
Rhythm Shimakawa is currently an Associate Professor at the Waseda Institute for Advanced Study (WIAS) and Center for Data Science at Waseda University. He obtained his Ph.D. from Osaka University in 2012. Before joining Waseda University, he was a NAOJ fellow of the National Astronomical Observatory of Japan (NAOJ). He has published over 100 articles that have received over 1,800 citations. His research interests include galaxy formation and evolution, data astronomy, and galaxy–black hole co-evolution, among others.
Journal
Monthly Notices of the Royal Astronomical Society Letters
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Spider-Webb: JWST Near Infrared Camera resolved galaxy star formation and nuclear activities in the Spiderweb protocluster at z = 2.16
Article Publication Date
18-Dec-2024
Chang’e-6 farside basalts reveal a reinforced lunar dynamo
image:
The ancient strength of the lunar magnetic field recorded by the Chang'e-6 basalt clasts reveal the existence of a relatively active lunar dynamo at 2.8 Ga.
view moreCredit: Image by ZHANG Min, QI Kaixian, and SHI Pingyuan
The evolution of the lunar dynamo is crucial for understanding the Moon’s deep interior structure, thermal history, and surface environment. A recent study by Chinese scientists conducted paleomagnetic analyses on basalts returned by the Chang’e-6 mission and revealed a significant reinforcement of the lunar dynamo approximately 2.8 billion years ago (Ga).
This groundbreaking work was published in Nature.
Previous paleomagnetic studies of nearside lunar samples have established a general timeline for the evolution of the Moon’s magnetic field. However, limited spatial and temporal constraints have left the evolutionary trajectory of the lunar dynamo unclear.
The Chang'e-6 mission, which returned the first farside basalt samples dated to approximately 2.8 Ga, provides a unique opportunity to fill this critical gap in our understanding of the lunar dynamo’s spatiotemporal evolution.
Led by Prof. ZHU Rixiang at the Institute of Geology and Geophysics of the Chinese Academy of Sciences (CAS), Associate Professor CAI Shuhui and her colleagues measured the ancient magnetic field strength from the Chang'e-6 basalts, obtaining values ranging from approximately 5 to 21 microteslas (µT).
These findings revealed an unexpected resurgence in field strength at 2.8 Ga, following a sharp decline around 3.1 Ga. This challenges the prevailing hypothesis that the lunar dynamo entered a low-energy state after 3 Ga and remained in this condition until its cessation.
The researchers proposed that the lunar magnetic field during this period may have been driven by a basal magma ocean and/or powered by precessional forces. Additional mechanisms, such as core crystallization, may have also a role.
These findings suggest that the Moon’s deep interior remained hot and geologically active well into its mid-early history.
This study represents the first ever paleomagnetic data obtained from the Moon’s farside, providing critical insights into the intermediate stages of the lunar dynamo’s evolution. By synthesizing this data with existing findings, the researchers suggested significant fluctuations in the lunar magnetic field between 3.5 and 2.8 Ga, indicating a highly unstable dynamo during this period.
These results offer valuable guidance for future lunar exploration missions, including the search for potential magnetic reversals.
The research was conducted in collaboration with the National Astronomical Observatories, CAS. Lunar samples were supplied by the China National Space Administration, and the study was supported by the National Natural Science Foundation of China, the Strategic Priority Research Program (Category B) of CAS, and the Key Research Program of the Institute of Geology and Geophysics, CAS.
Journal
Nature
Article Title
A reinforced lunar dynamo recorded by Chang’e-6 farside basalt
Article Publication Date
19-Dec-2024
Study reveals origins of lunar water and its connection to earth's early history
The team analyzed water in nine samples from the Apollo lunar mission, using a high-precision triple oxygen isotope technique. This method, developed by Dr. Morgan Nunn Martinez of the University of California, San Diego, separates water into its various binding phases—loosely bound, tightly bound, and trapped within minerals—via stepwise heating at 50°C, 150°C, and 1,000°C. Their findings provide crucial evidence that lunar water has a dual heritage: one part originating from early Earth-like material and another delivered through cometary impacts.
"This is a major step forward in unraveling where lunar water comes from," Dr. Maxwell Thiemens of the AMGC research group of the VUB explained. "Our data suggest that the Moon inherited water tracing back to Earth's formation, followed by later contributions from comets, delivering the water reservoirs we see today."
Three key results are central to the report. An early Earth signature: The oxygen isotopic composition closely matches enstatite chondrites, a meteorite type believed to be the building blocks of the Earth. There are also clear signs of cometary contribution: A significant portion of lunar water shows isotopic similarities to comets. A reducedimportance of solar wind: the study challenges the prevalent theory that the majority of lunar water was produced in situ via solar interactions with lunar silicates, presenting instead a complex mixing of sources.
This discovery is timely as nations and private enterprises intensify their efforts to establish permanent lunar bases. Understanding the water’s origins and distribution could have significant implications for sustaining human presence on the Moon.
"The data not only enhance our understanding of the Moon’s past but also pave the way for future space exploration and resource utilization. These findings should redefine how we think about water as a resource for long-term lunar habitation." Thiemens concludes.
This research has the potential to shape lunar and planetary science for decades to come, offering a deeper connection between Earth's water-rich environment and the Moon’s arid surface. With Artemis missions on the horizon, this pioneering study provides a crucial foundation for future exploration and resource planning.
Reference:
M.M. Thiemens, M.H.N. Martinez, M.H. Thiemens, Triple oxygen isotopes of lunar water unveil indigenous and cometary heritage, Proc. Natl. Acad. Sci. U.S.A. 121 (52) e2321069121, https://doi.org/10.1073/pnas.2321069121 (2024)
Journal
Proceedings of the National Academy of Sciences
DOI
Back to the past: The death of stars reveals their birth
Following a backward approach in the history of these celestial bodies, researchers at SISSA have achieved a new result that defines the mass of newly formed stars, even in previously unreachable parts of the cosmos
Scuola Internazionale Superiore di Studi Avanzati
A new article published in “Universe” describes an approach that looks back from the deaths of stars to their births, allowing the so-called initial mass function (IMF), i.e. the way in which star masses are distributed after their formation, to be derived from observations of supernovae and gamma radiation. By applying a common computational method of parameter estimation, scientists have managed to derive the IMF of regions of the cosmos that are too distant for direct observation by telescope. The work was conducted by a team of researchers from the Scuola Internazionale Superiore di Studi Avanzati (SISSA) of Trieste, the National Institute for Nuclear Physics (INFN), the Institute for Fundamental Physics of the Universe (IFPU) and the National Institute for Astrophysics (INAF).
The IMF obtained by the authors of the study was surprisingly similar to that measured in regions of the Universe closest to us. The scientists consider this to be possible evidence of a universal IMF. The result will now be tested by observations made by telescopes such as the JWST and Euclid.
Is the IMF a universal constant? Possibly
“All stellar populations observed in our neighbourhood appear to display a surprisingly similar initial mass function (IMF). This may indicate that the IMF is a universal constant of star formation in any region of the Universe. Unfortunately, instrumental limitations prevent scientists from examining stellar populations beyond the local Universe to test the IMF universality” explains Francesco Gabrielli, researcher and author of the study, along with Andrea Lapi and Mario Spera.
Star formation is one of the most fascinating processes in the Universe, occurring in dense internal regions of galaxies through the collapse and fragmentation of clouds of molecular gas. When a mass of gas becomes sufficiently hot and dense it starts burning hydrogen, and shining: this is when a star is born.
Supernovae and gamma-ray bursts used to calculate the IMF
The new research began with a backward look and, more specifically, from the knowledge that the course of a star's life depends on its mass. Massive stars end their lives in spectacular explosions called supernovae. Some supernovae are believed to eject a high-velocity jet of material that emits gamma-rays in a so-called “gamma-ray burst.” Since the occurrence of a particular type of explosion depends on the mass of the star, the number of such explosions occurring in the Universe will depend on the number of stars that form with the right mass - in other words, on the IMF.
Francesco Gabrielli explains: "My group and I have developed a new method, based on these considerations, to determine the IMF beyond the local Universe. In particular, we have used a computational method that is actually quite common but has now been used for the first time to reproduce the number of supernovae and gamma-ray bursts observed in the Universe. Since these quantities depend strictly on the IMF, this has allowed us to precisely determine the form of the IMF that best represents the observations".
Test by observation
Using this approach for the first time, the researchers succeeded in developing a new methodology for determining IMF. One particularly fascinating discovery was that the IMF calculated for the distant Universe was surprisingly similar to that measured in the local Universe, providing possible evidence of a universal IMF.
Gabrielli concludes: “This is an exciting time for astrophysicists, with many new telescopes such as the JWST and Euclid now beginning to take observations. As a result, exceptional numbers of observations of supernovae and gamma-ray bursts are expected in the coming years. It will be exciting to see what this new wealth of data can tell us about the IMF and its universality. A deeper understanding of the IMF would lead to important advances in various areas of astrophysics, including the formation and evolution of stars, the chemical enrichment of the Universe, and the observation of gravitational waves emitted by colliding black holes”.
Journal
Universe
Subject of Research
Not applicable
Article Title
Constraining the Initial Mass Function via Stellar Transients
University of Houston scientists solving meteorological mysteries on mars
Groundbreaking new paper answers key climate questions
University of Houston
image:
Comparison of Mars and Earth REB
view moreCredit: Univ. of Houston Dept. of Physics
A groundbreaking achievement by scientists at the University of Houston is changing our understanding of climate and weather on Mars and providing critical insights into Earth’s atmospheric processes as well.
The study, led by Larry Guan, a graduate student in the Department of Physics at UH's College of Natural Sciences and Mathematics, under the guidance of his advisors, Professor Liming Li from the Department of Physics and Professor Xun Jiang from the Department of Earth and Atmospheric Sciences and several world-renowned planetary scientists, generated the first-ever meridional profile of Mars’ radiant energy budget, or REB, which represents the balance or imbalance between absorbed solar energy and emitted thermal energy across the latitudes. On a global scale, an energy surplus leads to global warming, while a deficit results in global cooling. Furthermore, the meridional profile of Mars’ REB fundamentally influences weather and climate patterns on the red planet.
The findings are in a new paper just published in AGU Advances and will be featured in AGU’s prestigious science magazine EOS.
“The work in establishing Mars’ first meridional radiant energy budget profile is noteworthy,” Guan said. “Understanding Earth’s large-scale climate and atmospheric circulation relies heavily on REB profiles, so having one for Mars allows critical climatological comparisons and lays the groundwork for Martian meteorology.”
The profile, based on long-term observations from orbiting spacecraft, offers a detailed comparison of Mars’ REB to that of Earth, uncovering striking differences in the way each planet receives and radiates energy. While Earth exhibits an energy surplus in the tropics and a deficit in the polar regions, Mars displays the opposite configuration.
“On Earth, the tropical energy surplus drives warming and upward atmospheric motion, while the polar energy deficit causes cooling and downward atmospheric motion,” Jiang explained. “These atmospheric motions significantly influence weather and climate on our home planet. However, on Mars, we observe a polar energy surplus and a tropical energy deficit.”
That surplus, Guan says, is especially pronounced in Mars’ southern hemisphere during spring, playing a critical role in driving the planet’s atmospheric circulation and triggering global dust storms, the most prominent feature of Martian weather. These massive storms, which can envelop the entire planet, significantly alter the distribution of energy, providing a dynamic element that affects Mars’ weather patterns and climate.
“The interaction between dust storms and the REB, as well as with polar ice dynamics, brings to light the complex feedback processes that likely shape Martian weather patterns and long-term climate stability,” Guan said.
Earth’s global-scale energy imbalance has been recently discovered, which significantly contributes to global warming at a magnitude comparable to that caused by increasing greenhouse gases. Mars presents a distinct environment due to its thinner atmosphere and lack of anthropogenic effects. The research team is now examining potential long-term energy imbalances on Mars and their implications for the planet’s climate evolution.
“The REB difference between the two planets is truly fascinating, so continued monitoring will deepen our understanding of Mars’ climate dynamics,” Li said. "This research not only deepens our knowledge of the red planet but also provides critical insights into planetary atmospheric processes.”
Also contributing to this major achievement were UH graduate students Ellen Creecy and Xinyue Wang, renowned planetary scientists Germán Martínez, Ph.D. (Houston’s Lunar and Planetary Institute), Anthony Toigo, Ph.D. (Johns Hopkins University) and Mark Richardson, Ph.D. (Aeolis Research), and Prof. Agustín Sánchez-Lavega (Universidad del País, Vasco, Spain) and Prof. Yeon Joo Lee (Institute for Basic Science, South Korea).
Journal
AGU Advances
Method of Research
Observational study
Subject of Research
Not applicable
Article Title
Distinct Energy Budgets of Mars and Earth
Article Publication Date
19-Dec-2024
New evidence exists for hidden water reservoirs and rare magmas on ancient Mars
Rice University research findings have ‘significant implications for habitability’
A new study explores how variations in Mars’ crustal thickness during its ancient history may have influenced the planet’s magmatic evolution and hydrological systems. The research, published in Earth and Planetary Science Letters, suggests that the thick crust of Mars’ southern highlands formed billions of years ago generated granitic magmas and sustained vast underground aquifers, challenging long-held assumptions about the red planet’s geological and hydrological past.
The study, led by Rice University’s Cin-Ty Lee, demonstrates that the southern highlands’ thick crust — up to 80 kilometers in some areas — was hot enough during the Noachian and early Hesperian periods (3-4 billion years ago) to undergo partial melting in the lower crust. This process, driven by radioactive heating, could have produced significant amounts of silicic magmas such as granites and supported subsurface aquifers beneath a frozen surface layer.
“Our findings indicate that Mars’ crustal processes were far more dynamic than previously thought,” said Lee, the Harry Carothers Wiess Professor of Geology and professor of Earth, environmental and planetary sciences. “Not only could thick crust in the southern highlands have generated granitic magmas without plate tectonics, but it also created the thermal conditions for stable groundwater aquifers — reservoirs of liquid water — on a planet we’ve often considered dry and frozen.”
The research team — including Rice professors Rajdeep Dasgupta and Kirsten Siebach, postdoctoral research associate Duncan Keller, graduate students Jackson Borchardt and Julin Zhang and Patrick McGovern of the Lunar and Planetary Institute — employed advanced thermal modeling to reconstruct the thermal state of Mars’ crust during the Noachian and early Hesperian periods. By considering factors such as crustal thickness, radioactive heat generation and mantle heat flow, the researchers simulated how heat affected the potential for crustal melting and groundwater stability.
Their models revealed that regions with crustal thicknesses exceeding 50 kilometers would have experienced widespread partial melting, producing felsic magmas either directly through dehydration melting or indirectly via fractional crystallization of intermediate magmas. Moreover, due to the elevated heat flow, the southern highlands’ thick crust would have sustained significant groundwater aquifers extending several kilometers below the surface.
The study challenges the notion that granites are unique to Earth, demonstrating that Mars could also produce granitic magmas through radiogenic heating even without plate tectonics. These granites likely remain hidden beneath basaltic flows in the southern highlands, offering new insights into Martian geology. Additionally, the research highlights the possible formation of ancient groundwater systems in Mars’ southern highlands, where high surface heat flux reduced the extent of permafrost and created stable subsurface aquifers. These reservoirs of water might have been periodically accessed by volcanic activity or impacts, resulting in episodic flooding events on the planet’s surface.
The findings have significant implications for habitability as the presence of liquid water and the ability to generate granitic magmas, which often contain elements critical for life, suggest that Mars’ southern highlands may have been more hospitable for life in the past than previously thought.
“Granites aren’t just rocks; they’re geological archives that tell us about a planet’s thermal and chemical evolution,” said Dasgupta, the Maurice Ewing Professor of Earth, Environmental and Planetary Sciences. “On Earth, granites are tied to tectonics and water recycling. The fact that we see evidence for similar magmas on Mars through deep crustal remelting underscores the planet’s complexity and its potential for hosting life in the past.”
The study highlights regions on Mars where future missions could focus on detecting granitic rocks or exploring ancient water reservoirs. Large craters and fractures in the southern highlands, for example, may provide glimpses into the planet’s deep crust.
“Every insight into Mars’ crustal processes brings us closer to answering some of the most profound questions in planetary science, including how Mars evolved and how it may have supported life,” Siebach said. “Our research provides a roadmap for where to look and what to look for as we search for these answers.”
This research was made possible by NASA grant 80NSSC18K0828 .
Journal
Earth and Planetary Science Letters
Article Title
Crustal thickness effects on chemical differentiation and hydrology on Mars
